CT5052 Network Operating Systems - Lecture Notes PDF

Lecture 7 CT5052 -Network Operating Systems Unix Command Utilities Overview oRevision oPathname oCopy,Move and Replace oPermission Modification Creation of a file: There are two methods to create a file: o The ‘cat’ utility. o The ‘touch’ command.  Displaying the contents of a Text file:...

Lecture 7 CT5052 -Network Operating Systems Unix Command Utilities Overview oRevision oPathname oCopy,Move and Replace oPermission Modification Creation of a file: There are two methods to create a file: o The ‘cat’ utility. o The ‘touch’ command.  Displaying the contents of a Text file: The cat utility displays the contents of a text file. Deleting a file: The ‘rm’ (remove) command is used to delete a file. Deleting a directory/folder: The ‘rmdir’ (remove directory) is used to delete a directory. We cannot delete the working directory or a directory that contains files. If you need to delete a directory with files in it, first delete the files (using rm) and then delete the directory. $ rmdir /home/samin/folder1 If we need to delete a directory that contains files or other sub-directories than we can also use a recursive function. With the rm command you can use the ‘-r’ option which is the recursive option. This option remove directories and their contents recursively. $ rm –r /home/samin/folder2 Relative Pathname A relative pathnames traces a path from the working directory to a file. Any pathname that does not begin with the root directory (/) is a relative pathname. Relative pathnames can describe a path through many directories. Samin could have created the Nepal directory more easily using a relative pathname: $ pwd /home/dipeshor $ mkdir Nepal The pathname used in this example is a simple filename. Relative Pathname: Example If we need to create a directory named “Kathmandu” inside the Nepal directory, we can use the relative pathname something like this: $ pwd /home/dipeshor $ mkdir Nepal/Kathmandu Absolute Pathname: Any pathname that begins with the root directory (/) is a Absolute pathname. If we need to create a directory named “Pokhara” inside the Nepal directory, we can use the absolute pathname something like this: $ pwd /home/dipeshor $ mkdir /home/dipeshor/Nepal/Pokhara Copy, Move and Rename: The ‘cp’ command is used to copy files and directories from one directory to another, as path determines. Command: cp file1 [Directory Path] Command: cp -r folder1 [Directory Path]  Copy, Move and Rename: (Continue) The ‘mv’ command is used to move files and directories from one working directory to another, as path determines. The ‘mv’ command is also used to rename files and directory. Command: mv file1 [Directory Path] [Here, the file1 will move to another directory] Command: mv file1 [Directory Path]/file2 [Here, the file1 will move to another directory with different filename as file2] Command: mv file1 file2 [Here, the file1 will rename to file2] Access Permission: Three types of users can access a file: the owner of the file (owner) - user, a member of a group to which the owner belongs (group), and everyone else (other). A user can attempt to access an ordinary file in three ways – by trying to read from, write to, or execute it. Three types of users, each able to access a file in three ways, equal a total of nine possible ways to access an ordinary file. Access Permission: The owner of a file can try to: read from the file write to the file execute the file A member of the owner’s group can try to: read from the file write to the file execute the file Anyone else can try to: read from the file write to the file execute the file The ‘ls’ utility with the –l and –g options When you call ls with the –l (long) option and the name of a file, ls displays a line of information about the file. When called with –g (group) it displays information about the group the file belongs to. Utility (Contd.) Use of the ‘chmod’ command The ‘chmod’ command is used to give read, write and execute permissions to the files and folders on the basis of user, group and others. Symbolic Permission Notation: So, let’s create a file named file1 and set its permissions. User: The user can read, write and execute it. Group: The group members can read and execute it. Others: Others may read it. Command: chmod u=rwx,g=rx,o=r file1 Use of the ‘chmod’ command Octal Number Permissions: Command: chmod 754 file1 Here, the digits 7, 5 and 4 each individually represent the permissions for user, group, and others. The digits 7, 5 and 4 are the combination of the numbers 4, 2, 1 and 0. 4 stands for “read”, 2 stands for “write”, 1 stands for “execute”, and 0 stands for “no permission.” chmod (example) chmod (contd.)  Thank You!! Any Questions?  Lecture 8 CT5052 Network Operating Systems GREP and Aliasing Regular Expression: Regular Expression provides an ability to match a “string of text” in a very flexible and concise manner. A “string of text” can be further defined as a single character, word, sentence or pattern of characters. GREP (Global Regular Expression Print) Command: The ‘grep’ command is used to print the lineup text and the regular expressions. Search for a text in a normal file: Command: grep “Brad William” names.txt Usage of ‘-w’ whole word option: Command: grep –w “Brad William” names.txt Avoiding case sensitive: GREP is case sensitive, but we can avoid case sensitive by using the ‘- i’ option. Finding the Line Number: We can use the ‘-n’ option in the grep command for finding the line number of the matched line. Usage of ‘-v’ option: In the grep command, the ‘-v’ option ignores the line of the searched string. Display certain non-matched lines with line containing matched string in GREP Use the -A command line option to print 'N' lines after the matched line. Display certain non-matched lines with line containing matched string in GREP Similarly, the -B command line option is used to display lines before the matched line. Display certain non-matched lines with line containing matched string in GREP To print lines around the matched line, use the -C command line option. Only print matched strings in GREP You are also allowed to only print the matched string on the standard output (instead of complete lines that get displayed by default). This feature can be accessed using the -o command line option. Aliasing: Aliases are like custom shortcuts used to represent a command (or set of commands) executed with or without custom options. List Currently Defined Aliases in Linux You can see a list of defined aliases on your profile by simply executing alias command. Defining an alias temporarily: $ alias shortname=‘your custom command here’ Note: Alias once defined on a shell is just stored for that current running session only. Once, the session is closed the defined alias gets removed and won’t be preserved for another session. Defining an alias permanently: You need to set the alias on the ‘.bashrc’ file which is the configuration file of the bash, to keep the alias preserved in every session. Removing an alias: $ unalias lsl Any Questions? Thank You!!!  Week 9 Active Directory Domain Services (AD DS) Identity and Access (IDA) An IDA infrastructure should: Store information about users, groups, computers and other identities. An identity is representation of an entity that will perform actions on a server. A component of the IDA is the identity store that contains properties that uniquely identify the object such as: User name Security identifier (SID) password The Active Directory (AD) data store is an identity store. The directory itself is hosted on and managed by a domain controller – a server performing the Activity Directory Domain Services (AD DS) role. IDA responsibilities Authentication AD uses Kerberos Authentication Access Control Maintains an Access Control List (ACL) Reflects a security policy composed of permissions that specify access levels for particular identities. Audit Trail Allows monitoring of changes and activities within the IDA infrastructure IDA Technologies Supported by AD Identity Applications Trust Integrity Partnership Identity Active Directory Domain Services (AC DS) A central repository for identity management. Provides authentication and authorization services through Group Policy. Provides information management and sharing services enabling users to find any component by searching the directory. Applications Application Directory Lightweight Directory Services (AD LDS) Essentially a standalone version of AD Stores and replicates only application related information. Commonly used by applications that require a directory store but do not require information to be replicated as widely as to all domain controllers. Allows you to deploy a custom schema to support an application without modifying the AD DS schema. Formally know as Active Directory Application Mode (ADAM) Trust Active Directory Certificate Services (AD CS) Used to set up a certificate authority for issuing digital certificates as part of a public key infrastructure (PKI) that binds the identity of a person, device, or service to a corresponding private key. If you use AD CS to provide these services to external communities, then AD CS should be linked with an external renowned CA. Integrity Active Directory Rights Management Services (AD RMS) An information-protection technology that enable you to implement persistent usage policy templates that define allowed and unauthorized used e.g. you could configure a template that allows users to read a document but not to print or copy its contents. Partnership Active Directory Federation Services (AD FS) Enables an organization to extend IDA across multiple platforms including both Windows and non-Windows environments. Projects identity and access rights across security boundaries to trusted partners. Supports single sign-on (SSO) Beyond IDA AD delivers more than IDA solutions AD provides the mechanisms to support, manage, and configure resources in a distributed network environment. Schema Policy-based administration Replication services Schema A set of rules that defines the classes of objects and attributes that can be contained in the directory. e.g. the fact that AD has user objects that include a user name and password is because the schema defines the user object class that, the two attributes, and the association between the object class and attributes. Policy-based administration Provides a single point at which to configure settings that are then deployed to multiple systems. Such policies include; Group policy Audit policies Fine-grained password policies Replication Services Distribute directory data across a network This includes both the data store itself as well as data required to implement policies and configuration, including logon scripts. Global Catalog Enables you to query AD and locate objects in the data store. Contains information about every object in the directory. Can be used by programmatic interfaces such as Active Directory Services Interface (ADSI) and Lightweight Directory Access Protocol (LDAP). Components of an AD Infrastructure Activity Directory data store Domain controller Domain Forest Tree Functional level Organizational unit (OU) Sites Active Directory Data Store AD DS stores its identities in the directory – a data store on domain controllers The directory is a single file named Ntds.dit that is located in the %SystemRoot%\Ntds folder on a domain controller The database is divided into several partitions, including the schema, configuration, global catalog, and the domain naming context. Domain Controller (DC) The DCs are servers that perform the AD DC role. The DCs also run the Kerberos Key Distribution Center (KDC) service. Domain Requires one or more DCs DCs replicate the domain’s partition of the data store so that any DC can authenticate any identity in the domain. Is a scope of administrative policies such as password complexity and account lockout policies. Forest A collection of one or more AD domains. The first domain installed in a forest is called the forest root domain. A forest contains a single definition of network configuration and a single instance of the directory schema. A forest is a single instance of the directory – no data is replicated by AD outside the boundaries of the forest. A forest defies a security boundary. Tree The DNS namespace of domains in a forest creates trees within the forest. If a domain is a subdomain of another domain, the two domains are considered a tree. The domains must constitute a contiguous portion of the DNS namespace. Trees are the result of the DNS names chosen for the domains in a forest. Functional Level The functionality available in an AD domain or forest depends on its functional level. The three domain functional levels are: Windows 2000 native Windows Server 2003 Windows Server 2008 The functional level determines the versions of Windows permitted on domain controllers. Organization Units (OU) OUs provide a container for objects and provide a scope with which to manage objects. OUs can have Group Policy Objects (GPOs) linked to them. GPOs can contain configuration settings that will then be applied automatically by users or computers in an OU. Sites An AD site is an object that represents a portion of the enterprise within which network connectivity is good. A site creates a boundary of replication and service usage. DCs within a site replicate changes within seconds. Changes are replicated between sites on a controlled basis with the assumption that intersite connections are slow, expensive, or unreliable compared to the connections within a site. Clients will prefer to use distributed services provided by servers in their site or in the closest site. Thank You  Week 6 Unix Utilities Overview Getting Started UNIX The UNIX File System Some UNIX Commands 2 What is an Operating System? 3 What is an Operating System? An operating system is a control program for a computer. It has two main functions: to allocate computer resources and schedule tasks; to provide interfaces to the user. It performs many sub-functions almost simultaneously. It schedules tasks so that the central processor is working on only one task at a given moment. 4 The UNIX Operating System UNIX is the name of a family of computer operating systems and their family of related utility programs. 5 Layers of an UNIX system 6 Overview of the UNIX System 7  The UNIX File System (hierarchical file structure) ▪ A hierarchical structure frequently takes the shape of a tree. ▪ In a UNIX system, each user starts with one directory. ▪ Typically, each subdirectory is dedicated to a single subject. 8 Directory and Files · Files are at the ends of paths. · Directory files, or directories, are the points that other paths can branch off from. · Directories directly connected by a path are called parents (closer to the root) and children (farther from the root). 9 Filenames Every file has a filename. You will avoid confusion if you choose characters from the following list: uppercase letters (A-Z) lowercase letters (a-z) numbers (0-9) underscore (_) period (.) comma (,) The only exception is the root directory, which is always named /. 10 Filename Extensions · Filename extensions help to describe the contents of the file. · A filename extension is the part of a filename following an embedded period. · It makes filenames easy to understand. · You can use several periods within the same filename (for example, notes.30.09.2003). Filename Meaning of Filename Extension compute.c A C programming language source file computer.o The object code for the program computer The same program as an executable file memo.0410 A text file 11 Invisible Filenames A filename beginning with a period is called an invisible filename because the ls command without options does not normally display it. The command ls –a displays all filenames, even invisible ones. Startup files are usually invisible. Two special invisible entries, a single and double period (. and..), appear in every directory. 12 UNIX Command · The basis of all UNIX interactions is the command. · A command given by you forces your computer (system) to do what you want. · A UNIX command is an action request given to the UNIX shell for execution. · It may be entered at a console or included in executable files to form scripts. 13 Command Syntax · Commands are entered at the shell prompt (for example, the Korn shell $ prompt). · The command format is: $ verb [options] [arguments] · The brackets indicate that the options and arguments are optional. · The verb is the command name. · The option modifies how the action is applied. · The argument provides additional information to the command. 14 Command Syntax (contd…) · You must know, for each command, what are the options and what are the arguments. · The general format or syntax of a command may be represented graphically like this: 15 Example: Command Without Options and Arguments · The command used to determine the current directory is print working directory (pwd). · It has no options and no arguments. · When executed, it prints the absolute pathname for the current directory. 16 Example: Command With Options and Arguments · To create a new directory, you use the make directory (mkdir) command. · It has two options: permission mode and parent directory (try man mkdir). 17 Absolute Pathnames Every file has a pathname. You can build the pathname of a file by tracing a path from the root directory, through all the intermediate directories, to the file. This path of filenames is called an absolute pathname. 18 The Working Directory The directory you are associated with, or are working in, is called the working directory, or the current directory. The pwd (print working directory) utility displays its pathname. To access a file in the working directory, you do not need a pathname – just a simple filename. To access a file in another directory you must use a pathname. 19 Your Home Directory When you first log in on a UNIX system, the working directory is you home directory. To display the absolute pathname of your home directory, use pwd just after you log in. 20 Startup Files · An important file in your home directory is a startup file. It gives the operating system specific information about you as a user. · Either you or the system administrator can put a startup file, containing shell commands, in your home directory. · The shell executes the commands in this file each time you log in. · With the Bourne shell and the Korn shell, the filename must be.profile. · Because the startup files have invisible filenames, you must use ls –a command to see these files in your home directory. · You can put your own commands in your startup files. 21 Creating a Directory The mkdir utility creates a directory. It does not change your association with the working directory. The argument you use with mkdir becomes the pathname of the new directory. 22 Creating a Directory: Example I 23 Creating a Directory: Example II · If there are no files in the directory, ls does not list anything. 24 The. and.. Directory Entries · The mkdir utility automatically puts two entries in every directory. · The. is synonymous with the pathname of the working directory and can be used in its place. You can think of. as being a shortcut version of the current directory. If you are in "/home/max" then "." (by itself or followed by a '/') is equivalent to "/home/max" · The.. is synonymous with the pathname of the parent of the working directory, a shortcut version of the directory above. 25 Any Questions? Thank You!! 26  Week 5 Overview of Network Operating System II Objectives 5.1 Recap 5.2 Characteristics of a Network Operating System 5.2 Windows 5.3 Linux 5.4 Determining Software Requirements 5.1 Characteristics of a Network Operating System 5.1 Characteristics of a Network Operating System 5.1.1 Overview of NOS Characteristics Network operating systems (NOSs) distribute their functions over several networked computers. It then adds functions that allow access to shared resources by several users concurrently. Client systems contain specialized software that allows them to request shared resources that are controlled by server systems responding to a client request. 5.1 Characteristics of a Network Operating System 5.1.2 Differences Between PC and a NOS The NOS enhances the reach of the client PC by making remote services available as extensions of the local native operating system. Although a number of users may have accounts on a PC, only a single account is active on the system at any given time. NOS supports multiple user accounts at the same time and enables concurrent access to shared resources by multiple clients. 5.1 Characteristics of a Network Operating System 5.1.3 MultiUser, Multitasking, and Multiprocessor Systems A NOS server is a multitasking system. Internally, the OS must be capable of executing multiple tasks or processes at the same time. Some systems are equipped with more than one processor, called multiprocessing systems. They are capable of executing multiple tasks in parallel by assigning each task to a different processor. The aggregate amount of work that the server can perform in a given time is greatly enhanced in multiprocessor systems. 5.1 Characteristics of a Network Operating System 5.1.4 NOS Server Hardware NOS servers are large systems with additional memory to support multiple tasks that are all active, or resident, in memory at the same time. Additional disk space is also required on servers to hold shared files and to function as an extension to the internal memory on the system. Because a NOS depends on the continuous operation of its servers, the extra hardware components justify the additional expense. 5.1 Characteristics of a Network Operating System 5.1.5 CPU Architectures A program is a sequence of stored instructions, and a CPU executes these instructions by following a specific instruction set. There are two distinct types of instruction sets that CPUs may use: Reduced Instruction Set Computer (RISC) - This architecture uses a relatively small set of instructions. RISC chips are designed to execute these instructions very rapidly. Complex Instruction Set Computer (CISC) - This architecture uses a broad set of instructions, resulting in fewer steps per operation. 5.1 Characteristics of a Network Operating System 5.1.6 Enhancing CPU Operation Intel processors use Hyper-Threading to enhance the performance of some of their CPUs. With Hyper-Threading, multiple pieces of code (threads) are executed simultaneously in the CPU, so a single CPU performs as though there are two CPUs. AMD processors use HyperTransport to enhance CPU performance. HyperTransport is a high-speed connection between the CPU and the Northbridge chip. The power of a CPU is measured by the speed and the amount of data that it can process. The speed of a CPU is rated in cycles per second, such as millions of cycles per second, called megahertz (MHz), or billions of cycles per second, called gigahertz (GHz). The amount of data that a CPU can process at one time depends on the size of the front side bus (FSB). 5.1 Characteristics of a Network Operating System 5.1.7 Multicore Processors Integrating the processors on the same chip creates a very fast connection between them. Multicore processors execute instructions more quickly than single-core processors. Instructions can be distributed to all the processors at the same time. RAM is shared between the processors because the cores reside on the same chip. 5.1 Characteristics of a Network Operating System 5.1.8 RAID Concepts Storage devices can be grouped and managed to create large storage volumes with redundancy. To do so, computers can implement redundant array of independent disks (RAID) technology. Higher levels of RAID, such as RAID 5, 6, or 10 use striping and parity in combination to provide speed and to create large volumes. The figure shows the details about the RAID levels. RAID levels higher than 10 combine lower RAID levels. For example. RAID 10 combines RAID 1 and RAID 0 functionalities. 5.1 Characteristics of a Network Operating System 5.1.9 Cloud Computing and Virtualization Virtualization enables a single computer to host multiple independent virtual computers that share the host computer hardware. Without virtualization, cloud computing, as it is most-widely implemented, would not be possible. Traditionally, organizations delivered applications and services to their users using powerful dedicated servers. Problems with the traditional server deployment approach include: - Wasted resources - Single-point of failure - Server sprawl 5.1 Characteristics of a Network Operating System 5.1.9 Cloud Computing and Virtualization A special program called the hypervisor is used to manage the computer resources and various VMs. It provides VMs access to all of the hardware of the physical machine such as CPUs, memory, disk controllers, and NICs. Each of these VMs runs a complete and separate operating system. With virtualization, enterprises can now consolidate the number of servers. It is not uncommon for 100 physical servers to be consolidated as virtual machines on top of 10 physical servers using hypervisors. 5.1 Characteristics of a Network Operating System 5.1.9 Cloud Computing and Virtualization The hypervisor, also called the Virtual Machine Manager (VMM), is the brain of virtualization. There are two types of hypervisors: Type 1 (native) hypervisor – Also called bare-metal hypervisor and typically used with server virtualization. Type 2 (hosted) hypervisor – This is hosted by an OS and is commonly used with client-side virtualization. 5.1 Characteristics of a Network Operating System 5.1.9 Cloud Computing and Virtualization All virtual machines share the following basic system requirements: Processor support – Processors from Intel and AMD, were specifically designed to support virtualization. Processors with multiple cores are recommended as the additional cores increase speed and responsiveness when running multiple VMs and cores can be dedicated to specific VMs. Memory support – You need enough RAM for each virtual OS. Storage - Each active VM will require storage space. Therefore, large and fast drives are recommended. Network Requirements – Network connection requirements depend on the type of VM. To connect a VM uses a virtual network adapter that simulates the real host adapter. In certain setups a dedicated NIC is provided exclusively to the VM. 5.1 Characteristics of a Network Operating System 5.1.10 Choosing a NOS The main features to consider when selecting a NOS include: - Performance - Management and monitoring tools - Security - Scalability - Robustness/fault tolerance 5.1 Characteristics of a Network Operating System 5.1.11 Types of Network Operating System It is important to know the basics about popular NOS families. Many networks now include more than one server type, and knowing how to get these diverse systems to interoperate is an important skill for a network administrator. Operating systems on the network have their own language. Different NOS vendors use the same terms in different ways. 5.2 Windows 5.2 Windows 5.2.1 Windows Terminology Windows server-based networks that run Windows Server are based on the concept of the domain and Active Directory. A domain is a group of computers and users that serves as a boundary of administrative authority. 5.2.2 Windows 20XX Family of OS 5.3 Linux 5.3 Linux 5.3.1 History of Linux Linux is an operating system like UNIX. It runs on many different computers and was first released in 1991. Linux is portable, which means versions can be found running on name brand or clone PCs. Linux offers from other versions of UNIX. many features adopted 5.3 Linux 5.3.3 Linux Operating System Linux is sometimes referred to as "UNIX Lite", and it is designed to run on Intel- compatible PCs. However, Linux will run on other machines as well. Linux brings the advantages of UNIX to home and small business computers. The following are a few of the most popular types: - Ubuntu Server - Red Hat Enterprise Linux Linux Mandrake - SUSE Linux Enterprise Server Debian GNU/Linux - CentOS 5.3 Linux 5.3.4 Linux Clients Windows clients can access Linux servers without client software if the UNIX servers run Samba, which is a program that uses the Server Message Block (SMB) application layer protocol. Windows computers use SMB for file access across the network. Samba permits them to see the Linux file system. 5.4 Determining Software Requirements 5.4 Determining Software Requirements 5.4.1 Workstation Software and Programs The X Window System is what comprises the Linux GUI environment. FreeOffice 2021 and LibreOffice are the top two office suites capable of running on Linux. There also But also cloud driven solutions that you can use if you are connected to the internet like Google Docs, or MsOffice365 if you are that determined. 5.4 Determining Software Requirements 5.4.1 Workstation Software and Programs Some of the popular audio and visual programs available for Linux include tools for viewing and editing graphics like XV and GIMP. 5.4 Determining Software Requirements 5.4.2 Server Software and Programs A popular use of a Linux system is a web server. Web server software uses Hypertext Transfer Protocol (HTTP) to deliver files to users that request them, using a web browser from their workstation. A Mail Server is a system that is configured with the proper programs and services that enable handling the exchange of e-mail sent from one client to another. The Linux operating system provides file server either in a Linux environment or in a cross-platform environment consisting of Windows, Macintosh, UNIX, or OS/2 workstation. 5.4 Determining Software Requirements 5.4.2 Additional Software and Programs There are some programs and software that are essential to add to a Linux system regardless of whether it is configured as a workstation or a server. Text editors are essential for performing any type of maintenance tasks that a user or an administrator may need to do. Some examples of text editors available in Linux are vi, jed, pico, or Emacs. 5.4 Determining Software Requirements 5.4.2 Additional Software and Programs Programming tools are helpful Linux servers as well to specific users at workstations if they are programmers. These programming tools are also referred to as compilers or interpreters. A compiler converts the program source code, which is written by the programmer into binary form the computer can read. Common scripting languages include Javascript, Python, and Perl. Every Linux system relies on a library called the C library (libc). Linux systems rely on the C library for the routines that are necessary for C programs to run in Linux. 5.4 Determining Software Requirements 5.4.3 Verifying Software Compatibility When installing a package, the first step should be to always check and make sure that the operating system supports the package. Generally, any Linux software and package can be installed on any UNIX-like operating system. Check CPU requirements, library requirements, and development tools. Conclusion 5.1 Characteristics of a Network Operating System 5.2 Windows 5.3 Linux 5.4 Determining Software Requirements Any Questions??  Week 4 Overview of Network OS Services Agenda Recap Network OS Services Remote Administration and Access Services Directory Services Other NOS Services Recap Roles of Server Primary Subsystems that makes server hardware Types of server : Tower, Rack and Blade 2 Partition Schemes : MBR and GPT 3 boot options: Optical media, USB, Network Boot A database that stores low level settings of windows OS is windows registry Which server requires less cabling? Blade Server The first Windows Server OS? Windows NT 3.1 Which command is correct? a) $pwd=readHost -asecured String b) $pwd=read-host as -Secured String c) $pwd=read-host -assecurestring d) $pwd=read-host -assecuredString Which command is correct? a) $pwd=readHost -asecured String b) $pwd=read-host as -Secured String c) $pwd=read-host -assecurestring d) $pwd=read-host -assecuredString Primary Partitions in MBR? 4 Partitions 4.1 Network/NOS Services 4.1 An Introduction to Network/NOS Services Networking Operating Systems are designed to provide network services to clients and peers. Network services include the World Wide Web (WWW), file sharing, mail exchange, directory services, remote management, and print services. Most popular network services rely on the TCP/IP suite of protocols. 4.2 Remote Administration and Access Services 4.2 Remote Administration and Access Services 4.2.1 Remote Access With a remote access connection, employees can access the corporate remote access server and log in to the network with their regular user account. Employees can then use all the resources that would be available from the office desktop computer. 4.2 Remote Administration and Access Services 4.2.2 Telecommuting Telecommuting is attractive to employees because it saves travel time and other costs associated with working in an office. Telecommuting tools such as email, phone, chat and video apps 4.2 Remote Administration and Access Services 4.2.3 Mobile Users It can be difficult or impossible to store all the files needed on a laptop or notebook computer. It is a security threat as well because the laptop and its contents could be physically stolen or broken. A better solution is for mobile users to dial in to the company LAN. 4.2 Remote Administration and Access Services 4.2.4 Terminal Emulation Services Terminal emulation is the process of accessing a remote system via a local computer terminal. The local terminal runs software that emulates, the look of the remote system terminal. The local user can type commands and execute programs on the remote system. 4.2 Remote Administration and Access Services 4.2.5 Telnet Services Telnet is the main Internet protocol for creating a connection with a remote machine. It gives the user the opportunity to be on one computer system and do work on another. But Telnet protocol has the following security considerations: - Hacking - Password guessing - Denial of Service (DoS) attacks - Packet sniffing (viewable text data) 4.3 Directory Services 4.3 What is Directory Services? An IT infrastructure for storing and mapping of resource information that are accessed frequently on daily basis. It is a centralized storage, so that we can access it across the globe. It is relatively faster Eg: Employee profile records, DNS Servers 4.3 Directory Services 4.3.1 Directory Service Standards To operate within a NOS, different directory services need to have a common method of naming and referencing objects. X.500 defines the Electronic Directory Service (EDS) standards. 4.3 Directory Services 4.3.2 Network Information Service (NIS) Linux uses its own version of Directory Services called the Network Information Service (NIS). The network consists of the NIS server, slaves, and clients. The NIS Servers is where the NIS database is created and maintained. The NIS databases are copied to all the NIS slave servers. 4.4 Other NOS Services 4.4 Other NOS Services 4.4.1 Mail Virtually all mail services rely on TCP/IP Mail services are comprised of a combination of the following components: - Mail Transfer Agent (MTA) - Mail Delivery Agent (MDA) - Mail User Agent (MUA) 4.4 Other NOS Services 4.4.2 Printing When a user decides to print in a networked printing environment, the job is sent to the appropriate queue for the selected printer. Print queues stack the incoming print jobs and service them using a "First In, First Out" (FIFO) order. It is placed at the end of the list of waiting jobs and is printed after all other previous jobs before it. 4.4 Other NOS Services 4.4.3 File Sharing File sharing is often done using the File Transfer Protocol (FTP) within a home or office network. Peer-to-peer networking is popular among home users, but the technology has yet to be deployed as a widespread business solution. Peer-to-peer protocols work without a central server. 4.4 Other NOS Services 4.4.4 Internet The World Wide Web is now the most visible network service. In less than a decade, the internet has become a global network of information, commerce, education, and entertainment. 4.4 Other NOS Services 4.4.5 Intranet Intranets use the same technology used by the Internet, including HTTP over TCP/IP, web servers, and web clients. The difference between an intranet and the Internet is that intranets do not allow public access to private servers. This is typically accomplished by using an Internet firewall. 4.4 Other NOS Services 4.4.6 Extranet Extranets are configured to allow employees and customers to access the private network over the Internet. To prevent unauthorized access to the private network, extranet designers must use a technology such as virtual private networking. VPNs rely on encryption software, usernames, and passwords to ensure that communication occurs privately, and only among authorized users. 4.4 Other NOS Services 4.4.7 Domain Name Service (DNS) The DNS protocol allows clients to make requests to DNS servers in the network for the translation of names to IP addresses. The Internet name that the DNS resolves to the IP address is also called the Hostname. The first part of the hostname is called the Machine Name, and the second part is called the Domain Name. 4.4 Other NOS Services 4.4.8 Dynamic Host Configuration Protocol (DHCP) Dynamic Host Configuration Protocol (DHCP) enables computers on an IP network to receive network configurations from the DHCP server. These servers have no information about the individual computers until information is requested. DHCP also allows for recovery and the ability to automatically renew network IP addresses through a leasing mechanism. This mechanism allocates an IP address for a specific time period, releases it and then assigns a new IP address. Conclusion Network OS Services Remote Administration and Access Services Directory Services Other NOS Services Thank You  Week 3 Physical Components of a Network Objectives 2.1 Topologies 2.2 Media Types 2.2 Network Devices 2.1 Topologies 2.1 Topologies 2.1.1 The Network Topology The network topology defines the layout of the network. It shows how devices on the network are interconnected. Devices on the network are termed nodes. A network has both a physical topology and a logical topology. 2.1 Topologies 2.1.1.1 Physical Topology Physical topology shows the physical configuration of a network, which refers to the actual physical layout of the devices and media.  2.1 Topologies 2.1.1.2 Logical Topology Logical topology refers to the paths that signals travel from one point on the network to another. 2.1.2 Identifying Network Topologies 2.1.2.1 Star Topology The star topology is the most used architecture in Ethernet LANs and resembles spokes in a bicycle wheel. A star topology generally costs more to implement than the bus topology because more cable is used and a central device is needed, such as a hub, switch, or router. 2.1.2 Identifying Network Topologies 2.1.2.2 Ring Topology A frame, called a token, travels around the ring and stops at each node. If a node wants to transmit data, it adds that data and the addressing information to the frame. The advantage of using this method is that there are no collisions of data packets. 2.1.2 Identifying Network Topologies 2.1.2.2 Mesh Topology The mesh topology connects all devices (nodes) to each other for redundancy and fault tolerance. It is used in wide-area networks (WANs) to interconnect LANs and for critical networks. The mesh topology is expensive and difficult to implement. 2.1.2 Identifying Network Topologies 2.1.2.2 The Hybrid Topology The hybrid topology combines more than one type of topology. When a bus line joins two hubs of different topologies, the configuration is called a star bus. The bus line is used to transfer the data between the star topologies. 2.2 Media Types 2.2 Media Types 2.2.1 Networking Media Networking media can be defined simply as the means by which signals (data) are sent from one computer to another. This includes cable or wireless means. There are a wide variety of networking media in the marketplace. 2.2.1 Networking Media 2.2.1.1 Twisted – Pair Cable Twisted-pair is a type of cabling that is used for telephone communications and most modern Ethernet networks. A pair of wires forms a circuit that can transmit data. The pairs are twisted to prevent cross talk. 2.2.1.1 Twisted – Pair Cable 2.2.1.1.1 Shielded twisted-pair (STP) STP cable combines the techniques of cancellation and twisting of wires with shielding. Each pair of wires is wrapped in metallic foil to further shield the wires from noise. The four pairs of wires are then wrapped in an overall metallic braid or foil. 2.2.1.1 Twisted – Pair Cable 2.2.1.1.2 Unshielded twisted-pair (UTP) Unshielded twisted-pair (UTP) has two or four pairs of wires. UTP is the most commonly used cabling in Ethernet networks. 2.2.1 Networking Media 2.2.1.2 10 Gb Ethernet Cable Demands for high bandwidth keep increasing. 10Gbps calls for new specifications of twisted pair copper cabling. Ethernet cable with higher bandwidth such as Cat6, Cat6a, and Cat7 cables are introduced for high- speed applications 2.2.1 Networking Media 2.2.1.2 Fiber-Optic Cable Fiber-optic cable is a networking medium that is capable of conducting modulated light transmissions. To modulate light is to manipulate it so that it travels in the way that it transmits data. It refers to cabling that has a core of glass or plastic (instead of copper), through which light pulses carry signals. 2.2.1 Networking Media 2.2.1.4 Wireless Wireless networks use radio frequency (RF), laser, infrared (IR), and satellite/microwaves to carry signals from one computer to another without a permanent cable connection. No physical medium is necessary for wireless signals. Mobile phones are a common application of wireless. 2.2 Network Devices 2.2 Network Devices 2.2.1 Bridge The function of the bridge is to make intelligent decisions about whether or not to pass signals on to the next segment of a network. When a bridge sees a frame on the network, it looks at the destination MAC address and compares it to the forwarding table to determine whether to filter, flood, or copy the frame onto another segment. 2.2 Network Devices 2.2.2 Switches Switches learn certain information about the data packets that they receive from computers on the network. They use this to build forwarding tables to determine the destination of data being sent by one computer to another on the network. They help segment a network and reduce network traffic congestion by limiting each port to its own collision domain. 2.2 Network Devices 2.2.2 Routers Routers can be computers with special network software installed on them or they can be other devices built by network equipment manufacturers. Routers are capable of segmenting the network. Routers are capable of segmenting a network into multiple collision domains as well as into multiple broadcast domains. Conclusion Topologies Media Types Network Devices Thank You  Week 2 Windows Server 2022 Overview Objectives 2.1 Getting Started with Windows server 2.2 Introducing Windows server 2022 2.3 Installing Windows server 2022 2.4 Post Installation task on windows server 2022 2.1 Getting Started with Windows server 2.1.1 Understanding what a server does Server is a computer that is meant to be a dedicated service provider, Client is a computer that requests services. Client/server network : network that is made up of dedicated servers and clients. Plan your server for future growth 2.1 Getting Started with Windows server 2.1.2 Understanding the server roles A server role is a primary duty that a server performs: Some of the more common server roles include: File services Email Server Print services Database Server Web services Remote Access Application Server 2.1 Getting Started with Windows server 2.1.2 Selecting Server Hardware Primary Subsystem that makes the server hardware: Processor Memory Storage Network 2.1 Getting Started with Windows server 2.1.2 Types of Server Tower Server Standalone, upright cabinet, also known as a chassis configuration 2.1 Getting Started with Windows server 2.1.2 Types of Server Rack Server Mounted on a server rack in a data center. Plays an all-around computing role in the data center, supporting a multitude of workloads. 2.1 Getting Started with Windows server 2.1.2 Types of Server Blade Server Compact device that houses multiple thin, modular circuit boards called server blades. Each blade contains a single server, which is often assigned to one application. 2.1 Getting Started with Windows server 2.1.2 Types of Server 2.1 Getting Started with Windows server Understanding windows server Windows Server is the server's operating system developed by Microsoft as part of the Windows NT family of operating systems. 2.2 Introducing Windows Server 2022 Latest version of windows server operating system Windows Server 2022 Datacenter Edition is the most comprehensive edition designed for enterprises that own highly virtualized data-centers or act as cloud providers. Windows Server 2022 Standard Edition is the full-featured edition designed for medium-sized businesses that own servers on-premises. Windows Server 2022 Datacenter: Azure Edition this is intended only for running in the Microsoft cloud. 2.2 Introducing Windows Server 2022 Windows server 2019 vs Windows server 2022 New windows Admin center Upgraded Hyper-V Manager Enhanced Security Hybrid Cloud Capabilities 2.2 Introducing Windows Server 2022 Recommended Hardware Requirement for Windows server 2022 2 GHz 64-bit processor Compatible with x64 instruction set 32 GB for Server with Desktop Experience installation option 256 GB SSD, 1 TB HDD An ethernet adapter capable of at least 1 gigabit per second throughput Compliant with the PCI Express architecture specification. Graphics device and monitor capable of Super VGA (1024 x 768) or higher- resolution 2.3 Installing Windows server 2022 Understanding Partition Schemes: Master Boot Record (MBR): This is an old partition scheme known today as a legacy boot option. Operates on a 512-byte disk sector Maximum of four primary partitions, or three primary partitions and one extended partition. An extended partition can have up to 26 logical partitions Support disks up to 2TB 2.3 Installing Windows server 2022 Understanding Partition Schemes: GUID Partition Table (GPT): New partition scheme that overcomes the limitations of the MBR Operates on a 512-byte and up disk sector, most common 4096 byte Part of the Unified Extensible Firmware Interface (UEFI) Standard that replaces the old basic input/output system (BIOS) to Support modern hardware. Support disks up to 18 EB and 128 partitions 2.3 Installing Windows server 2022 Boot Options: Optical Installation Media USB Drive Network Boot 2.3 Installing Windows server 2022 Accessing Advanced Startup Options 1.Click the Start button. 2. Select Settings from the Start menu. 3. In Windows | Settings, select Update & Security. 4. Select Recovery from the navigation menu on the left side of the screen. 5. Click the Restart now button and then click on Continue: 2.3 Installing Windows server 2022 Various Windows Server 2022 Installation Methods: Clean installation Installation over a network using WDS Unattended installation In-place upgrade Migration 2.3 Installing Windows server 2022 Performing Clean Installation: 1. Turn on your computer, depending on the selected boot option, and wait for the boot prompt on the screen. The message on the screen requires user confirmation to boot the system from a DVD, USB flash drive, or network boot. 2. The installation files are loaded in RAM, 2.3 Installing Windows server 2022 Performing Clean Installation: 3. Enter your Languages and Preferences 2.3 Installing Windows server 2022 Performing Clean Installation: 4. Click Install 2.3 Installing Windows server 2022 Performing Clean Installation: 5. Select Windows Server 2022 Datacenter (Desktop Experience) and then click Next 2.3 Installing Windows server 2022 Performing Clean Installation: 6. Take your time to read the license terms. When done, check I accept the license terms and then click Next, 2.3 Installing Windows server 2022 Performing Clean Installation: 7. Select Custom: Install Windows only (advanced), as shown in Figure 2.3 Installing Windows server 2022 Performing Clean Installation: 8. After preparing the drive, select the partition where you want to install Windows Server 2022 2.3 Installing Windows server 2022 Performing Clean Installation: 9. Windows Setup is installing Windows Server 2022 2.3 Installing Windows server 2022 Performing Clean Installation: 10. After getting the devices ready and performing a few restarts, set up the administrator password 2.3 Installing Windows server 2022 Performing Clean Installation: 11. Congratulations! You have successfully installed Windows Server 2022. 2.4 Post Installation task on windows server 2022 Understanding the devices and device drivers Device Manager is used to manage device drivers Status of Device Manager: Generic A black exclamation point inside a yellow triangle A downward black arrow 2.4 Post Installation task on windows server 2022 Understanding the windows server registry Windows Registry is a hierarchical database that stores the hardware/software configuration and system security information. HKEY_CLASSES_ROOT: HKEY_CURRENT_USER:. HKEY_LOCAL_MACHINE: HKEY_USERS: HKEY_CURRENT_CONFIG: 2.4 Post Installation task on windows server 2022 Using Server Manager in Desktop Experience 2.4 Post Installation task on windows server 2022 Understanding Windows Server initial configuration using server manager Changing the server name, Joining a domain (this depends on the role of the server), Enabling Remote Desktop, Setting up a static IP address, Changing the time zone, Activating Windows Server 2022, Turning off Internet Explorer (IE) enhanced security, and checking for updates. Thank You  Week 1 Network Operating System Fundamentals About Me Mr. Dipeshor Silwal (Module Leader) Msc(IT) Data Analytics, Islington College (London Metropolitan University) Associate Program Leader AI FYP Supervisor More than 6 Years at Islington College What your module is ? Semester long Module 15 Weeks Study of Network Operating systems (Windows / Linux Servers) Operations of Network Operating systems Virtualizations Understand security and troubleshooting inside Network Operating System Aims of the module To understand the importance of Network operating systems (NOS) To explain the operation of Network operating systems, and their benefits To describe hardware requirements for the effective operation of NOS Aims of the module (contd..) To compare some of the most commonly available NOS, and their abilities and limitations To understand the concept of virtualization and its application in modern server environments To understand server documentation, security and trouble shooting Module learning outcomes LO1. Understand how the modern Network operating systems work, and the interrelation between hardware and software; LO2. Explain the function and structure of modern Network operating systems; LO3. Identify the compare the most widely used Network operating system LO4. Use preventive maintenance to solve security upgrading issues in responsible and professional manner; LO5. Implement hardware and software troubleshooting techniques, and record and present the technical findings critically and effectively Syllabus Introduction to NOS, NOS clients Basic network design Microsoft (Windows Servers) Create users/profiles. Patching securing Active directory design Syllabus Domain controller function IIs Linux installation Linux Create users/profiles controlling services. NOS Server Hardware and software Server Virtualisation Network administration role and best practises server security Troubleshooting Assessments Unseen Theory Exam (Written , 50%) – Week 15 Practical Test (Logbook and practical test, 40%) – Week 13 Progress Test (MCQ, 10 %) – Week 11 Text Books IT Essentials II: Network Operating Systems Companion Guide (Cisco Networking Academy Program) (Cisco Networking Academy Program Series) ISBN-10: 1587130971 CompTIA Network+ Certification All-in-One Exam Guide, Seventh Edition (Exam N10-007) ISBN-10: 1260122387 Objectives 1.1 Operating System Basics 1.2 Network Operating System Overview 1.1 Operating System Basics 1.1.1 Overview of PC Operating System Desktop microcomputers first become popular and widespread in the early 1980s. Productivity of desktop computers was limited by their inability to share information easily with other system. 1.1 Operating System Basics 1.1.2 PCs and Computer Network Companies installed local-area networks (LANs) to connect desktop PCs so that the PCs could share data and peripherals, such as printers. Network operating system (NOS) requires more computing muscle than the desktop counterparts. 1.1 Operating System Basics 1.1.2 PCs and Computer Network A new breed of PCs was pressed into service as network servers. These computers ran a NOS and became the focal point of the PC-based LAN. 1.1 Operating System Basics 1.1.2 PCs and Computer Network Web browsing, electronic mail (e-mail), and other Internet-related applications are now the focus of home computing. To provide these Internet technologies, companies such as Microsoft have retooled their desktop operating systems. The desktop OS now includes many of the features and services that were once reserved for the NOS. 1.1 Operating System Basics 1.1.3 Kernel Kernel is the most common term for the core of the operating system. It is a small piece of code that is loaded into memory when the computer boots. This computer code contains instructions that allow the kernel to manage hardware devices, memory allocation, system processes, and other programs. 1.1 Operating System Basics 1.1.3 Kernel 1.1 Operating System Basics 1.1.4 User Interface Component of the OS that the user interacts with. The UI is like an interpreter, translating user keystrokes, mouse clicks, or other input for the appropriate programs. Allows the user to manipulate software using visual objects such as windows, pull-down menus, pointers, and icons. 1.1 Operating System Basics 1.1.4 User Interface 1.1 Operating System Basics 1.1.5 File System The file system provides the directory structure that organizes the user's operating system, application, configuration, and data files. File Allocation Table, 32-bit (FAT32) – A file system that can support partition sizes up to 2 TB or 2,048 GB. New Technology File System (NTFS) – A file system that can support partition sizes up to 16 Exabytes, in theory. 1.1 Operating System Basics 1.1.5 File System 1.1 Operating System Basics 1.1.6 Common Desktop Operating System Microsoft Windows one of the most popular operating systems today. Example: Windows 11, Window 10 , so forth. Apple Mac OS Apple computers are proprietary and use an operating system called Mac OS. Current versions of Mac OS are now based on a customized version of UNIX. 1.1 Operating System Basics 1.1.6 Common Desktop Operating System UNIX/Linux UNIX, which was introduced in the late 1960s, is one of the oldest operating systems. There are many different versions of UNIX, example Linux. Linux was developed by Linus Torvalds in 1991, and it is designed as an open-source operating system. Open-source programs allow the source code to be distributed and changed by anyone as a free download or from developers at a much lower cost than other operating systems. 1.2 Network Operating System Overview 1.2.1 Common Network Operating System Network OS - corporate environment Supports multiple users Runs multi-user applications Is robust Provides increased security compared to desktop operating systems Built-in networking components and network services, multiuser capability, and sophisticated file security and file sharing technologies Examples: Microsoft Windows: Windows Server 2022, and Windows Server 2019 Linux: Red Hat, Fedora, CentOS and so forth. 1.2 Network Operating System Overview 1.2.1 windows vs Linux NOS Comparison Windows has been marketed as a user-friendly, graphical interface (GUI), desktop operating system. The roots of Linux begin with UNIX and with that modular design made Linux a very popular choice among system administrators to run their servers. 1.2 Network Operating System Overview 1.2.2 windows vs Linux NOS Differences Text-mode interface functionality Cost Obtaining the OS Available application software Obtaining application software Virus vulnerability Security features Supporting multiple users 1.2 Network Operating System Overview 1.2.3 The Client-Server Model Most network applications, including Internet-related applications such as the World Wide Web (WWW) and e-mail, are built around a client/server relationship. A server offers network services, such as e-mail to other programs called clients. Once enabled, a server program waits to receive requests from client programs. If a legitimate request is received, the server responds by sending the appropriate information back to the client. 1.2 Network Operating System Overview 1.2.3 The Client-Server Model Any computer can act as a server as long as it is connected to the network and is configured with the appropriate software. Most organizations put all of their key network services on high-end computers called servers running NOSs optimized for servicing remote clients. 1.2 Network Operating System Overview 1.2.4 Evaluating Customer resources and Requirements One of the first things that must be taken into consideration when buying or building a new computer are the requirements that are needed to allow the system to efficiently provide the service. Determining the customer resources will also help decide on what type of system to build or buy for the customer. 1.2 Network Operating System Overview 1.2.4 Evaluating Customer resources and Requirements A Linux workstation is a system that is typically a standalone computer consisting of one monitor, keyboard, and mouse. Most often a workstation will be configured with a network connection as well. 1.2 Network Operating System Overview 1.2.4 Evaluating Customer resources and Requirements Servers really have no need to the user-oriented features like large monitors, speakers or sound card. They need to consist of things like reliable and fault tolerant hard disks. For this reason, servers will have large, high-performance hard disks such as Small Computer System Interface (SCSI) disks or solid-state drive (SSDs) 1.2 Network Operating System Overview 1.2.4 Evaluating Customer resources and Requirements Determining the customers resources is an important step in evaluating the requirements that are needed but also that will be available. These can include things like existing hardware, budgetary constraints, and having the proper expertise available. Linux provides and excellent means for reusing existing hardware and extending the life of old and otherwise unusable systems. Linux has the ability to run without a GUI that can use up all the system resources. One way to deal with budget constraints is to decide the proper hardware that is needed and what the user will need to accomplish the job. Thank You  Unix/Linux Command Reference File Commands 1. ls Directory listing 2. ls -al Formatted listing with hidden files 3. ls -lt Sorting the Formatted listing by time modification 4. cd dir Change directory to dir 5. cd Change to home directory 6. pwd Show current working directory 7. mkdir dir Creating a directory dir 8. cat >file Places the standard input into the file 9. more file Output the contents of the file 10. head file Output the first 10 lines of the file 11. tail file Output the last 10 lines of the file 12. tail -f file Output the contents of file as it grows,starting with the last 10 lines 13. touch file Create or update file 14. rm file Deleting the file 15. rm -r dir Deleting the directory 16. rm -f file Force to remove the file 17. rm -rf dir Force to remove the directory dir 18. cp file1 file2 Copy the contents of file1 to file2 19. cp -r dir1 dir2 Copy dir1 to dir2;create dir2 if not present 20. mv file1 file2 Rename or move file1 to file2,if file2 is an existing directory 21. ln -s file link Create symbolic link link to file Process management 1. ps To display the currently working processes 2. top Display all running process Unix/Linux Command Reference  3. kill pid Kill the process with given pid 4. killall proc Kill all the process named proc 5. pkill pattern Will kill all processes matching the pattern 6. bg List stopped or background jobs,resume a stopped job in the background 7. fg Brings the most recent job to foreground 8. fg n Brings job n to the foreground File permission 1. chmod octal file Change the permission of file to octal,which can be found separately for user,group,world by adding, 4-read(r) 2-write(w) 1-execute(x) Searching 1. grep pattern file Search for pattern in file 2. grep -r pattern dir Search recursively for pattern in dir 3. command | grep Search pattern in the output of a command pattern 4. locate file Find all instances of file 5. find. -name filename Searches in the current directory (represented by a period) and below it, for files and directories with names starting with filename 6. pgrep pattern Searches for all the named processes , that matches with the pattern and, by default, returns their ID System Info 1. date Show the current date and time 2. cal Show this month's calender 3. uptime Show current uptime 4. w Display who is on line 5. whoami Who you are logged in as Unix/Linux Command Reference  6. finger user Display information about user 7. uname -a Show kernel information 8. cat /proc/cpuinfo Cpu information 9. cat proc/meminfo Memory information 10. man command Show the manual for command 11. df Show the disk usage 12. du Show directory space usage 13. free Show memory and swap usage 14. whereis app Show possible locations of app 15. which app Show which applications will be run by default Compression 1. tar cf file.tar file Create tar named file.tar containing file 2. tar xf file.tar Extract the files from file.tar 3. tar czf file.tar.gz files Create a tar with Gzip compression 4. tar xzf file.tar.gz Extract a tar using Gzip 5. tar cjf file.tar.bz2 Create tar with Bzip2 compression 6. tar xjf file.tar.bz2 Extract a tar using Bzip2 7. gzip file Compresses file and renames it to file.gz 8. gzip -d file.gz Decompresses file.gz back to file Network 1. ping host Ping host and output results 2. whois domain Get whois information for domains 3. dig domain Get DNS information for domain 4. dig -x host Reverse lookup host 5. wget file Download file 6. wget -c file Continue a stopped download Unix/Linux Command Reference Shortcuts 1. ctrl+c Halts the current command 2. ctrl+z Stops the current command, resume with fg in the foreground or bg in the background 3. ctrl+d Logout the current session, similar to exit 4. ctrl+w Erases one word in the current line 5. ctrl+u Erases the whole line 6. ctrl+r Type to bring up a recent command 7. !! Repeats the last command 8. exit Logout the current session Unix/Linux Command Reference 12/25/22, 8:54 AM Evaluation Test NAME : CLASS : Evaluation Test 22 Questions DATE : 1. What is the Max File Size Fat32 File System holds? A 32GB B 128GB C 2GB D 4GB 2. which of the following is the function of an Operating System. A Memory Management B Process Management C Device Management D All of the above 3. The file System "NTFS" stands for ? A New Type File System B Never Terminated File System C New Technology File System D New Technology File Support 4. Peer to Peer Network is an example of ? A BUS Topology B Mesh Topology C Start Topology D None of the above. 5. which file system uses compression or supports compression? A NTFS B FAT32 C FAT16 D COM32 6. Token Ring is the Data link Technology For ? A WAN B MAN C LAN D TLAN https://quizizz.com/print/quiz/636db1dcee0858001d4517d8 1/4 12/25/22, 8:54 AM Evaluation Test 7. In the network of 20 Computers, which of the following topology require extensive cabling? A Mesh B Ring C Star D BUS 8. which topology has high rate of data collision? A Mesh B BUS C Ring D None of the mentioned. 9. The ______ is the physical path over which a message travels. A Security Policies B Medium C Runway D Route 10. which of the following device broadcast the packets all the time. A Bridge B Switch C HUB D Router 11. which one is the services of the server ? A File Service B Mail Service C Remote access D All of the above. 12. Firmware Interface Support of GPT is ? A BIOS B UEFI C GPEI D None of the above. 13. What is the Maximum partition capacity of MBR? A 2TB B 4TB C 8TB D 10TB 14. which of the following is the suitable answer for Windows Registry ? A Boot Option B BIOS C Low level Setting D Permission https://quizizz.com/print/quiz/636db1dcee0858001d4517d8 2/4 12/25/22, 8:54 AM Evaluation Test 15. Which type of server is slower in terms of speed? A Tower B Rack C Blade 16. The first Windows Server OS was? A Windows NT 2 B Windows NT 3.1 C Windows NT 4 D None of the above. 17. Which command is correct ? A $pwd=readHost -asecured String B $pwd=read-host as -Secured String C $pwd=read-host -assecurestring D $pwd=read-host -assecuredString 18. which one of the following is the Remote access tool? A Team Viewer B PuTTY C Both A and B D None of the above 19. what component of email is responsible for providing email service. A Male Transfer Agent B Mail Transfer Agent C Message Transfer Agent D Mail Delivery Agent 20. DHCP helps to ? Helps computer on an IP network to A B Provides Domain names receive Network configuration C enables remote access D None of the above 21. When was the first operating system developed? A 1965 B 1950 C 1955 D 1960 22. Network Operating system runs on _____? A Every system in the network B server C both a and b D none of the above https://quizizz.com/print/quiz/636db1dcee0858001d4517d8 3/4 12/25/22, 8:54 AM Evaluation Test Answer Key 1.d 2.d 3.c 4.b 5.a 6.c 7.a 8.b 9.d 10.c 11.d 12.b 13.a 14.c 15.c 16.b 17.c 18.c 19.b 20.a 21.b 22.c https://quizizz.com/print/quiz/636db1dcee0858001d4517d8 4/4 12/22/22, 10:58 AM MCQ Practice Questions NAME : CLASS : MCQ Practice Questions 40 Questions DATE : 1. Which of the following is not an operating system ? A Linux B Synix C Windows D DOS 2. What is the full form of FAT? A File allocation table B File action template C Font attribute table D File attribute table 3. Which command is used to make a hidden directory in linux? A mkdir hidden directoryName B mkdir -h directoryName C mkdir -hd directoryName D mkdir.directoryName 4. Which of the following command is used to list hidden files? A ls -ld B None of the options C ls -a D ls -al 5. A server ____ the request. A Hide B Request C Responds D Controls 6. In P2P there is ______. A Same computer as server/client B Dedicated Server C Multiple server D A server cannot act as client https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 1/7 12/22/22, 10:58 AM MCQ Practice Questions 7. Which command is used to delete non-empty directory. A rm -r dirName B rmdir -r dirName C rmdir dirName D rmdir -R dirName 8. The maximum file size of FAT32 system is_____? A 1TB B 4MB C 4 GB D 4.7GB 9. ISDN stands for? A Integrated Service Digital Network B Integrated Service Dark Network C International Standard for D Integrated Service for Digital Network 10. Firewall acts as ____ between networks. A None of all. B Border C Messenger D Barrier 11. _______ can be used to administer linux server remotely. A None of the options B SSH C Telnet/SSH anyone D Telnet 12. Which command overrides the content of a file? A cat filename B cat>>filename C cat -a filename D cat>filename 13. What does the following command do? mv file1 file2 A renames file1 to file2 B moves file1 and file2 C renames file2 to file1 D combines file1 and file2 https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 2/7 12/22/22, 10:58 AM MCQ Practice Questions 14. Who is the founder of Linux? A Linus Albert B Stephen Linux C Linux D D Linus Torvalds 15. I can see the content of the file but I cannot edit it. This means the file has ____. A Read permission B Only write permission C Only execute permission D No permissions 16. To change directory to 2 steps back which of the following command is used? A cd../../ B cd // C cd../../ D cd././ 17. which of the following is not a File system? A FAT32 B exFAT C REFS D MD5 18. I make requests and I receive responses. Who am I? A I don't know you B Client C Peers D Server 19. Which of the following is not an role of windows server? A Linux Integration B DNS server C None of the options D DHCP server 20. Which of the following is not available in windows server 2022 datacenter edition? A Storage Migration Service B Storage Spaces C Software-defined Networking D None of the options https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 3/7 12/22/22, 10:58 AM MCQ Practice Questions 21. To create user without password using powershell new-localuser -name "name" -description A None of the options B "desc" -nopassword newlocaluser -name "name" -description new-localusers -name "name" -description C D "desc" -nopassword "desc" -nopassword 22. In powershell to store input in a variable as secured string A $variable = read-host -asecuredstring B $variable = read-host -assecurestring C $variable = read-host -assecuredstring D $variable = red-host -assecurestring 23. To list all local user in Windows PowerShell. A get-alluser B get alluser C get -localuser D get-localuser 24. Inorder to get new user(user1) on login screen A user1 must create additional group B user1 must have lowercase name C user1 must be member of Users group D user1 must be string only 25. To add user in Users group add-newgroupmember -group add-localgroupmember -group A B "groupname" -member "user" "groupname" -member "user" add -newgroupmember -group add-groupmember -group "groupname" - C D "groupname" -member "user" member "user" 26. To remove a user named "tamayo" in powershell. A remove-localuser -name "tamato" B sudo remove-localuser -name "tamayo" C remove-user -name "tamayo" D remove-localuser -name "tamayo" 27. Which of the following is not a boot method? A CD-ROM B Hard drive C Network Drive D Wireless Card https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 4/7 12/22/22, 10:58 AM MCQ Practice Questions 28. Find out the odd one. A Guest User B Administrator C Superuser D Root 29. If the system is connected to a DHCP server it will provide the information automatically A False, It only provice Subnet B False, it cannot connect to network C False, it only provide IPV6 address D True 30. GRUB stands for A Grand Unified Buses B Grand Unified Bootloader C Grand Unit Bit D Grand Universal Bus 31. It is a good idea to make only root account in system. A False B None of the options C True D Maybe 32. IDA stands for A Identity and Access B None of the options C Install and Access D Integrity and Access 33. AD is controlled by A Controller B Direct Access C domain controller D DHCP server 34. Which of the following is not a responsibility of IDA? A Authentication B Audit Trial C Audit Tail D Access Control https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 5/7 12/22/22, 10:58 AM MCQ Practice Questions 35. AD uses ______ authentication A Karbaros B Kerbberos C Kerberos D Kubernetes 36. AD LDS Stands for Application Directory Legiment Directory Application Directory Lightweight A B Services Directory Services Access Directory Lightweight Directory Active Directory Lightweight Direct C D Services Services 37. A Set of rules that defines the classes of objects and attributes that can be contained in the directory. A Schema B Laws C Protocol D AD 38. Which of the following is not a component of AD structure? A Domain B Forest C DHCP D Domain Controller 39. Active directory data store file is named as? A Ntds.dir B None of the options C Ntds.dit D Ntd.dit 40. GUID stands for A Global User Identifiers B Globally unique identifier globally used international Directory C Graphical User interface Device D Services https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 6/7 12/22/22, 10:58 AM MCQ Practice Questions Answer Key 1.b 2.a 3.d 4.c 5.c 6.a 7.a 8.c 9.a 10.d 11.c 12.d 13.a 14.d 15.a 16.c 17.d 18.b 19.a 20.d 21.b 22.b 23.d 24.c 25.b 26.d 27.d 28.a 29.d 30.b 31.a 32.a 33.c 34.c 35.c 36.b 37.a 38.c 39.c 40.b https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 7/7 12/22/22, 10:58 AM MCQ Practice Questions NAME : CLASS : MCQ Practice Questions 40 Questions DATE : 1. Which of the following is not an operating system ? A Linux B Synix C Windows D DOS 2. What is the full form of FAT? A File allocation table B File action template C Font attribute table D File attribute table 3. Which command is used to make a hidden directory in linux? A mkdir hidden directoryName B mkdir -h directoryName C mkdir -hd directoryName D mkdir.directoryName 4. Which of the following command is used to list hidden files? A ls -ld B None of the options C ls -a D ls -al 5. A server ____ the request. A Hide B Request C Responds D Controls 6. In P2P there is ______. A Same computer as server/client B Dedicated Server C Multiple server D A server cannot act as client https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 1/7 12/22/22, 10:58 AM MCQ Practice Questions 7. Which command is used to delete non-empty directory. A rm -r dirName B rmdir -r dirName C rmdir dirName D rmdir -R dirName 8. The maximum file size of FAT32 system is_____? A 1TB B 4MB C 4 GB D 4.7GB 9. ISDN stands for? A Integrated Service Digital Network B Integrated Service Dark Network C International Standard for D Integrated Service for Digital Network 10. Firewall acts as ____ between networks. A None of all. B Border C Messenger D Barrier 11. _______ can be used to administer linux server remotely. A None of the options B SSH C Telnet/SSH anyone D Telnet 12. Which command overrides the content of a file? A cat filename B cat>>filename C cat -a filename D cat>filename 13. What does the following command do? mv file1 file2 A renames file1 to file2 B moves file1 and file2 C renames file2 to file1 D combines file1 and file2 https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 2/7 12/22/22, 10:58 AM MCQ Practice Questions 14. Who is the founder of Linux? A Linus Albert B Stephen Linux C Linux D D Linus Torvalds 15. I can see the content of the file but I cannot edit it. This means the file has ____. A Read permission B Only write permission C Only execute permission D No permissions 16. To change directory to 2 steps back which of the following command is used? A cd../../ B cd // C cd../../ D cd././ 17. which of the following is not a File system? A FAT32 B exFAT C REFS D MD5 18. I make requests and I receive responses. Who am I? A I don't know you B Client C Peers D Server 19. Which of the following is not an role of windows server? A Linux Integration B DNS server C None of the options D DHCP server 20. Which of the following is not available in windows server 2022 datacenter edition? A Storage Migration Service B Storage Spaces C Software-defined Networking D None of the options https://quizizz.com/print/quiz/63a3e6edb513f7001d6c6b4b 3/7 12/22/22, 10:58 AM MCQ Practice Questions 21. To create user without password using powershell new-localuser -name "name" -description A None of the options B "desc" -nopassword newlocaluser -name "name" -description new-localusers -name "name" -description C D "desc" -nopassword "desc" -nopassword 22. In powershell to store input in a variable as secured string A $variable = read-host -asecuredstring B $variable = read-host -assecurestring C $variable = read-host -assecuredstring D $variable = red-host -assecurestring 23. To list all local user in Windows PowerShell. A get-alluser B get alluser C get -localuser D get-localuser 24. Inorder to get new user(user1) on login screen A user1 must create additional group B user1 must have lowercase name C user1 must be member of Users group D user1 must be string only 25. To add user in Users group add-newgroupmember -group add-localgroupmember -group A B "groupname" -member "user" "groupname" -member "user" add -newgroupmember -group add-groupmember -group "groupname" - C D "groupname" -member "user" member "user" 26. To remove a user named "tamayo" in powershell. A remove-localuser -name "tamato" B sudo remove-localuser -name "tamayo" C remove-user -name "tamayo" D remove-localuser -name "tamayo" 27. Which of the f