Lesson 12(E).pdf

12 Web Hosting and Maintenance Lesson Introduction In the previous lesson you have learnt about event driven JavaScript functions and use of JavaScript Libraries such as JQuery. This week you will lean on web server systems for hosting web sites and maintaining websites remo...

12 Web Hosting and Maintenance Lesson Introduction In the previous lesson you have learnt about event driven JavaScript functions and use of JavaScript Libraries such as JQuery. This week you will lean on web server systems for hosting web sites and maintaining websites remotely and dynamically. This week focus on various hosting platforms, frameworks and maintenance facilities commonly in use. Learning Outcomes: After completion of this lesson, the learner will be able to host websites in remote locations and maintain the sites. This lesson enables you to Describe Web hosting platforms and methods Use remote login methods for hosting sites Create and maintain web content on remote sites Apply ftp, sftp and ssh clients Lesson Outline UNIX and Windows hosting Web servers, Server Packages and utilities (Apache, IIS, WAMP, LAMP etc..) Domain name registration and hosting options Web server ports and configurations Remote login protocols and facilities GUI web server control and cPanel File permissions, indexing and structuring Web maintenance client applications 12.1 Web Servers and hosting In previous lessons you have learnt about event driven JavaScript functions and their libraries. So, in this lesson, we will discuss how to host websites on different platforms with maintenance facilities. 12.1.1 Web Hosting In generally, the term Web hosting is refers to the activity or service of providing storage space to individuals or organizations, for their websites that are accessible via World Wide Web. Any website to be available for viewing on the World Wide Web, it has to be on a computer that is connected to the Internet. The computer your site is on is known as its host. A web host, or hosting service provider, is a business that provides the technologies and services needed for the website or webpage to be viewed in the Internet. Websites are hosted, or stored, on special computers with special software service called servers. You have to pay to an organization to put your documents on their webserver, which called as web hosting. Hosting service providers are hosting your site on their servers. When Internet users want to view your website, all they need to do is type your website address or domain into their browser. The DNS ensures you get associated with the correct computer. Their computer will then connect to your server and your webpages will be delivered to them through the browser. In the world of web site hosting there are two main types of operating system platforms on which you may host your web site, namely: UNIX and Windows (UNIX hosting and Windows hosting). 12.1.2 Windows Hosting Windows hosting means hosting of web services that runs on the Windows operating system and design their own sites using Microsoft technology means Windows-specific technologies such as ASP,.NET, Microsoft Access and Microsoft SQL server (MSSQL). You should choose Windows hosting if you plan to use ASP (Active Server Pages) or ASP.net as server scripting, or if you plan to use a database like Microsoft Access or Microsoft SQL Server. Some of the Windows-specific technologies such as ASP,.NET, Microsoft Access and Microsoft SQL server (MSSQL) are listed below. ASP.net - Active Server Pages Active Server Pages is a server-side scripting technology developed by Microsoft. With ASP you can create dynamic web pages by putting script code inside your HTML pages. Commonly used language is C#. The web server executes the code before the page is returned to the browser. Here on ASP.net, HTML, JavaScript, CSS and XML types of web languages are enabled. ASP is a standard component in current Windows OS’s. It can be activated on all computers running Windows. Many web hosting providers are offering ASP, as it is becoming a more and more popular technology. Currently ASP.net is more popular among Microsoft community. MySQL MySQL is also popular database software for web sites. MySQL is an inexpensive alternative to the expensive Microsoft and Oracle solutions. 12.1.3 Unix Hosting and Linux Hosting Unix hosting means hosting of web services that runs on the Unix operating system. Unix was the first (original) web server operating system, and it is known for being reliable and stable. It is less expensive than Windows. Linux hosting means hosting of web services that runs on the Linux operating system. Linux also belongs to same family of Unix, there are other variants like, FreeBSD, OpenBSD, Fedora (linux version) and CentOS. We run a derivative of Unix called Linux. We run 64-Bit Enterprise Linux servers. Linux servers are known for their value, stability and wide feature set. You do not have to be running Linux to use a hosting provider with Linux Servers. It is simply the software used by the server to share out a website. 12.2 Web servers, Server Packages and Utilities Here we discuss the particular software called a web server that responds to client side requests that comes from a web browser, by giving resources like XHTML Pages. Through this section you will get to know about two web servers the open source Apache HTTP Server and Microsoft’s Internet Information Services (IIS) which you can install on your own computer for testing your web pages and web applications. Web server is a computer where the web content is stored. Basically web server is used to host the web sites but there exists other web servers also such as gaming, storage, FTP, email etc. Web server responds to the client request (browser) in one of the following two ways: Sending the file to the client associated with the requested URL Generating response by invoking a script and communicating with database When client sends request for a web page, the web server search for the requested page if requested page is found then it will send it to client with an HTTP response. If the requested web page is not found, web servers will the send an HTTP response: Error 404 Not found. If client has requested for some other resources then the web server will contact to the application server and data store to construct the HTTP response. 12.2.1 What is ISP? An Internet service provider (ISP), also sometimes referred to as an internet access provider (IAP), is a company that offers its customers to access to the internet. The ISP connects to its customers using a data transmission technology appropriate for delivering internet protocols such as dial –up, DSL, cable modem, wireless or dedicated high-speed interconnections. ISP may provide Internet email accounts to users, which allow them to communicate with another by sending messages through their ISP servers. In the following section it discusses how to install the software you need for running web apps using Apache HTTP Server, Apache is a powerful web server supports in both windows and Unix platforms. It is open source software and freely available. There are packages, which could install Apache with other components such as PHP, Python, etc. 12.2.2 Apache web server on Linux Generally, Apache web server bundle is delivered with most Linux variant installation packages. Here, in the following video you can learn how to install it from scratch. Here it uses Ubuntu as the operating system and apache2 web server package where it is more similar in other Linux/Unix variants and webservers as well. Further the next video shows how to configure it from Operating System bundle. Apache2 installation Demo: https://www.youtube.com/watch?v=-q8Jj4aAWYw Apache web server configuration Demo: https://www.youtube.com/watch?v=UrPNg4tWjUI 12.2.3 IIS (Internet Information Server) Internet Information Services (IIS) is the Windows Web service that means IIS is web server that can be installed on Microsoft windows computers, once you installed IIS server to your own computers you can publish your web pages and web applications on your local computers. Internet Information Services is not installed on current Windows OS’s by default. The following video IIS Installation Demo: https://www.youtube.com/watch?v=I32AnqJzD58 Publishing web site in IIS Create a home page for your Web site. Name your home page file Default.htm or Default.asp.  Copy your home page into the default Web publishing directory for IIS (wwwroot). The default Web publishing directory is also called the home directory, and the location provided by Setup is \Inetpub\wwwroot. If your network has a name resolution system (typically DNS), then visitors can simply type your computer name in the address bar of their browsers to reach your site. If your network does not have a name resolution system, visitors must type the numerical IP address of your computer. Publish content on your FTP site Copy or move your files into the default FTP publishing directory. The default directory provided by Setup is \Inetpub\Ftproot. If your network has a name resolution system (typically DNS), then visitors can type ftp:// followed by your computer name in the address bar of their browsers to reach your site. If your network does not have a name resolution system, visitors must type ftp:// and the numerical IP address of your computer. Activity 12.1: Write the differences and similarities of Windows hosting and Linux hosting. 12.3 Domain name registration and hosting options 12.3.1 What is a Domain Name? A domain name is a unique name for a web site, like microsoft.com and w3schools.com. A domain name is a unique name that people type in the browser to open a particular website. For example, domain name for w3schools is w3schools.com. It's the name by which your site will be known on the web and the way individuals can discover it. It is the primary thing that your clients will type in their program to get to your site or on the other hand find it through web search tools, for example, Google or Bing. Your domain name should be important because it is the name that people have to remember and type in to get to your website. Domain names must be registered. When domain names are registered they are added to a large domain name register, and information about your site - including your internet IP address which is stored on a DNS server. DNS stands for Domain Name System. A DNS server is responsible for informing all other computers on the Internet about your domain name and your site address. 12.3.2 Registering a Domain Most people will register their domain name with their web host in an "all-in-one" hosting solution. Domains can be registered from domain name registration companies such as http://www.dotdnr.com or GoDaddy etc. These companies provide interfaces to search for available domain names and they offer a variety of domain name extensions that can be registered at the same time. Domain Name Registration provides registration services for.com.net.org.biz.info.us.nu.ws.cc and.tv domains. 12.3.3 Different Types of Web Hosting Options In tins section basically we discuss about 3 main hosting options. These are Shared Servers, Virtual Private Servers, and Dedicated Server. Shared Server Option: A Shared Server is a computer managed by your web facilitating organization that enables numerous sites to be hosted on one computer. One basic preferred standpoint is monthly rental fee that is being charged to the end client. In the event that you have a web site that is quite straightforward and utilized for the most part to advertise, at that point this might be the best choice cost aspect. A particular one web site completes a considerable measure of handling, gets huge amounts of guests, it can viably back off alternate sites on the web server. The computer assets are being shared among everybody. Dedicated Server: This is heading off to the total outrageous contrasted with a shared server and is likewise the most costly approach. You are basically paying a huge monthly rental fee to leased line for your own particular computer every month. This alternative is ideal on the off chance that you are doing on the web mission basic activities and your site is acquiring a considerable measure of cash basic to the business task. Virtual Private Server Hosting: This is another option for hosting a web site that might be a center ground between a “shared Server” and a “dedicated Server”. This is essentially taking the web server and cutting into a settled number of virtual servers with dispensed computer assets for each. Along these lines you don't need to stress on the off chance that another person is hindering the web server for you are just utilizing a piece of it. It is more costly than a shared server yet more affordable than a dedicated server. 12.4 Web server ports and configurations Previously on Linux Webserver configuration video you may have seen how to configure the webserver with their ports and IP addresses. In this section we discussed about Web server ports and configurations further. When considering any server machine that makes its services available to the Internet using numbered ports, one for each service that is available on the server. Most of the time the default port is used as 80. Each of the most well known services is available at a well-known port number. The following video demonstrates the on how to configure windows port for apache web server. Next video demonstrate on configuring both IIS and XAMP together. Configure Apache ports on windows: https://www.youtube.com/watch?v=St49oetWUMI Configure IIS ports: https://www.youtube.com/watch?v=62eAVotw9F4 12.5 Remote login protocols and facilities Remote login that allows users to login to host machines on a network and users can act like they were physically at the host machine location. According to the user’s authority level they can read, add, edit and delete files. There are two remote login protocols are TELNET and SSH. TELNET: The protocol TELNET is a TCP/IP standard for setting up a connection to a remote machine. TELNET enables a user’s to sign in to a remote machine over the Web by first making a TCP connection and pass the detail of the application from the user to the remote machine. Using TELNET protocol, an application program on the client's machine turns into the customer. The client's console and its screen likewise append specifically to the remote server. The remote logging activity depends on timesharing, whereby an approved client has a user name and a password to Logging to Remote Servers. SSH: The protocol Secure Shell abbreviate as SSH, it is another remote login protocol, which is based on UNIX programs. SSH protocol utilizes TCP for communications but is more powerful and flexible than TELNET and allows the user to more easily execute a single command on a remote customer. SSH utilizes encryption to secure the connection between a customer and a server. All client confirmation, outputs, commands, and documents transfers are encrypted to protect against attacks in the network. The following video demonstrate the use of secure shell client for remote server access and for ftp. Remote server access through secure shell: https://www.experts- exchange.com/videos/633/Using-Secure-Shell-SSH.html Activity 12.2: Self study about SFTP software and compare and contrast the features of SFTP and SSH protocols while distinguishing their facilities. 12.6 GUI web server control and cPanel To manage hosting environment most of the website owners use different kind of web hosting control panels. These control panels facilitates the server administration and allows users to manage multiple websites easily. There are some of the activities that most of the control panels support. Web server administration DNS management Email management Database administration FTP management 12.6.1 cPanel cPanel is one of the most widely used control panels for web hosting. It is a web-based interface and it is an online Linux-based web hosting control panel that provides a graphical interface and automation tools designed to simplify the process of hosting a web site. One of the widely used and well-known control panels is cPanel. There are also other alternatives that you could consider such as Plesk, ISPConfig, etc., cPanel provides a 3 tier structure that utilizes capabilities for administrators, resellers, and end-user website owners to control the various aspects of website and server administration through a standard web browser. It is easy to use, highly customizable and majority of the hosts are configured to serve its multiple layouts that are available. It comes with various pre-installed options, and from it you can manage email and FTP accounts, your add-on and subdomains, MySQL database, applications, security, and statistics. Everything that we’ve talked about in this guide you can find in cPanel. After installing and answering a few questions to customize your cPanel, you are ready to use it. It has an interface for website owners and server owners. Besides the already mentioned pre-installed options, you can add almost anything you want to. In  the Web Host Manager part of the cPanel, you can do all things that are related to administrative server hosting. There you can add and manage your accounts, create hosting plans, reseller accounts, change security features, configure server, scale your hosting capabilities and much more. While it is easy and intuitive enough for beginners, cPanel is powerful enough to meet the needs of more advanced users. 12.7 File permissions, indexing and structuring Files that are on machines with Unix and Linux operating systems can have file permission that means operating system knows how to deal with request to access the files. Read, Write and Execute are the three access types. Read - Indicate as r, users can only read files that have read access, these files are displayed to the users. users can’t do any modifications to these files Write - Indicate as w, users can do any modifications according to their requirements to the files that have write permission Execute - Indicate as x, files with execute access can be executed as programs by the user. There are three types of user groups associated with these access types. User - The owner of the file. Group - Other files, which are in the same folder or group. World - Everyone else. cPanel can use to manage file permission 12.8 Web maintenance client applications Website Maintenance includes all the activities expected to ensure the operational integrity of a website. Whatever these activities don't happen, the outcomes can be embarrassingly obvious. It is important to maintain your web site or keep updated all the activities of your web application to any business. Website is a worldwide window into your business and it can have a big impact on how the value of your product or service is perceived. A well- maintained website is critical for real-time service industries. All businesses need regular website maintenance to attract and retain customers, maintain search engine rankings and present new information, products and services to the public. Website maintenance is also required to maintain the value of the website over time. Owning a site, accompanies have certain obligations. You can’t just build it and forget it. Well you have to do regular website maintenance, it is a must if you want your site to be successful and up to date without any fault. Please refer the video and the content of the following site to obtain more information on web maintenance. http://www.diffily.com/articles/maintenance.htm Activity 12.3: Download and install FileZilla software and get familiar with the web maintenance facilities supported by the software. Summary Now you have completed learning lesson 12. We have discussed about Web hosting, web servers and configurations, remote management of websites and maintenance of websites.