Network Troubleshooting PDF

Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting Troubleshooting Network Issues: Network Cable is...

Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting Troubleshooting Network Issues: Network Cable is Unplugged The network issue called “network cable is unplugged” Intai( Ethernet Intel(R) [7)(7) 1219-V kit Connection Gonasction Properties 3 18- ¥ropmitien Xo indicates that the computer is not detecting an Ethernet Events Rosources Management Power Management connection correctly T Déver L Detzle e The this network adapter, The following propedies are avalable for this adapter, Clck the the property you want 1o change cn the left, and then select kss value value The following are potential solutions to this issue: on the riht Property Property: Value Protocol N5NS Offlcad Officad ~ [futo Negotiation Megotiation | PTP Hard T @ Restart the computer Aty Aot At Recewe Side Scaling Reduce Speed On Power Down g:fls gosfls hod?dancnq bm?du\cng profile @ Check the Ethernet network cable W W‘“ o yotom yolom owWer ower Saver TCP Checkoum Offload (IPv4) ¥CP ;CP Owo;k;m O\oEk:m Ofload (IPv6) (IPvE) @ Change the Ethernet Adapter’s Duplex Settings UDP Checkaum Offoad 1Pv) M» et it UDP Checksum Checksum Offiosd Offioad (IPv6) ¥ @ Disable the Ethernet Network Adapter @ @ Update the Update the Network Network Adapter Adapter Driver Driver Cancel =] Copyright ©© by Copyright by EC-Councll. All EC-Councll. All Rights Rights Reserved, Reserved. Reproduction ReproductionIs Strictly Strictly Prohibited Prohibited Troubleshooting Network Issues: Network Cable is Unplugged The network issue called “network cable is unplugged” indicates that the computer is not detecting an Ethernet connection correctly. This error can be viewed on the desktop or notification screen. This error is also visible in the status of the Ethernet network connection. However, this error is not specific to Ethernet; the error can also be observed if aa Wi-Fi connection is being used and would result in failure to connect to the Internet. Once a user encounters this error on their system, it is likely to occur every few hours/days. The reason behind this error varies according to the computer configuration. Some computers face this issue owing to outdated or faulty drivers, whereas other computers show this error because of a conflict between the computer/application and the connection speed. The following are potential solutions to this issue. Restart the Computer Restart the computer by powering down, wait for a few seconds, and then turn on the computer. Laptop users must take the following extra step: remove the battery and power supply cable and, if possible, wait for 10 min. After 10 minutes, reattach the battery, power supply cable, and start Windows again. Check the Ethernet Network Cable Check to ensure that both ends of the Ethernet cable are tight. Connect one end of the cable to the computer and the other end to the main network device, e.g., a router. If this did not help, then check whether there is any fault in the cable. Instead of purchasing a new cable, use the cable with different computers or temporarily swap the Ethernet cable with a good Ethernet cable. Module 16 Page 1944 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting Change the Ethernet Adapter’s Duplex Settings The duplex settings in Windows manage the direction of network communication. For the best performance, the duplex values are automatically set by Windows. Most users have reported that duplex settings caused the “network cable is unplugged” error and that their concern was resolved by changing the duplex settings. To change the duplex settings, follow the steps below. = Step 1: Right-click on the Start Menu button and select the Device Manager. Apps and Features Power Options Event Viewer System Device Manager Network Connections Disk Management Computer Management Windows PowerShell Windows PowerShell (Admin) Task Manager Settings File Explorer Search Run Shut down or sign out Desktop Figure 16.17: Selecting the “Device Manager” Module 16 Page 1945 Certified Cybersecurity Technician Copyright © by EG-Council EG-Gouncil All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting = Step 2: In the Device Manager, navigate to Network adapters and click on it to expand the list of network adapters. Browse to the Ethernet Adapter in use (Intel(R) Ethernet Connection (7) 1219-V). Right-click on the Ethernet Adapter and select Properties. A Device Manager File Action View Help e mOHEm B EXG v A RODW-059 » i Audio inputs and outputs » B Computer ) w Disk drives » U@ Display adapters > B Firmware » e Human Interface Devices » =@@ IDE ATA/ATAPI controllers = Keyboards » ([ Mice and cther peinting devices » T Monitors v. Network adapters @ Intel(R) Ethernet Connect-~ ™ "+~ M @F Qualcomm Atheros ARSS AR Update driver &F VMware Virtual Ethernet / Disable device &@F VMware Virtual Ethernet / Uninstall device @ WAN Miniport (IKEv2) GF WAN Miniport (1P) Scan for hardware changes &F & WAN Minipont Miniport (IPv6) 3e = & & WAN WAN Minipont Minipont (L2TP) I| (L2TP) @ WAN Miniport (Network Monitor) @ WAN Miniport (PPPOE) ' WAN Miniport (PPTP). &F WAN Miniport Minipont (SSTP) > @@ Ports (COM & LPT) L Dent Anieriee Avieriee Figure 16.18 Selecting “Properties” for the Ethernet adapter = Step 3: In the new window that opens, click on the Advanced button, and under Properties, navigate to and select Speed & Duplex. Intel(R) Ethernet Connection (7) 1213-V Properties Events Resources General Driver Detais el. The following properties are avalable for this net apter. Chick the property you want to change on the left, and then select ts value on the nght. Property: Value: Protocol NS Offload A IMo Negotiation ;] PTP Hardware Timestamp em ower Saver TCP Checksum Offload (IPv4) TCP Checksum Offload (IPv6) Transma Buffers UDP Checksum Offload (IPv4) UDP Checksum Offload (IPv6) v Cancel Figure 16.19: Selecting the “Speed & Duplex” property Module 16 Page 1946 Certified Cybersecurity Technician Copyright © by EG-Gouncil All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting = Step 4: Under the Value heading, change the value to 100 Mbps Half Duplex and then click OK. Intel(R) Ethernet Connection (7) 1219-V Properties X Events Resources Resources Power Management General General Advanced Driver Detals The following properties are available for this network adapter. Cick Chick the property you want to change on the left, and then select its value ononthe the nght. Property: Value: Protocol NS Offload ~ PTP Hardware Timestamp Receive Buffers Receive Side Scaing Scalng Reduce Speed On Power Down RSS load balancing profile Software Timesta System Idie Power Saver TCP Checksum Offload (IPv4) TCP Checksum Offload (IPv6) Transmt Buffers UDP Checksum Offload (IPv4) UDP Checksum Offload (IPv6) ¥v s == Figure 16.20: Changing the “Value” = Step 5: Restart the computer. Note: If this did not fix the problem, then change the value in Step 4 and check if the problem is resolved. Disable the Ethernet Network Adapter If the user is not using the network adapter, then it is advisable to disable it. This also applies to computers having built-in Ethernet adapters that run on Wi-Fi networks. To disable the Ethernet network adapter, perform the following steps: = Open Control Panel and click on Network and Internet. | | [[0 Control Panel Panel + @ (G ) 4 [ [ Control Panel Adjust your computer’s settings View by: Category ¥* ‘ System and Security User Accounts Review your computer's status Change account typetype Save backup copies of your fikes files with File History @P CGyhang gyyP Change account Backup and Backup and Restore Restore (Window: (Windows 7)7) i h‘! S i.- ‘ ~ Appearance and Personalization $[ Network and Network and Internet Internet = —_— View network View network status and tasks status and tasks '. Clock -\nd CIDCk and Region R(‘gion.,// Hardware and Sound * Change date, time, or number formats fl‘ fi' View dences View dences and printers and printers b.S f P A Aditadades Add s dence ase ofo Access e @ Let Windows suggest settings., S~ Programs Programs Optimize visual desplay visual display [-ry [‘r] Uninstall aa program Uninstall program Figure 16.21: Control Panel Module 16 Page 1947 Certified Cybersecurity Technician Copyright © by EG-Gouncil EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting = (Click on Network and Sharing Center. || {3' Network and Internet « v N ' »> Control Panel »> Network Network and and Internet Control Panel Home ChrralCane Home LA LyLY Network and Sharing Center -}' J' View network status and tasks =~ Connect to a network || View network computers and devices System and Security J *o Network Network and Hardware and Internet Internet and Sound Hardware and Sound @ e] Internet Options Change your homepage homepag ~ Manage Manage browser browser add-ons ~ Delete Delete browsing history and cookies Programs j’ i) Infrared Send or recerve a file User Accounts Appearance and Personalization Clock and Region Ease of Access Figure 16.22: Click “Network and Sharing Center” = Click on Change adapter settings. (Click &% Network and Sharin Sharing Cente L o €« v~ 4 5% 5> ControlPanel » Network Network and Internet and Internet > Network Network and Sharing Center Control Panel Home View your basic network information and set up connections ] View your active networks Change Change adapter settings Change advanced sharing Network Access type: Intemet Internet seltings settings Private network Connections: Connections; |[ Ethemet Change your networking settings &t- - Set up a new connection or network Set up a broadband, dial-up, or VPN connection; of et up a router or access point, (= ’i] Troubleshoot problems Diagnose and repair network problems, or get troubleshooting information, Figure 16.23: Select “Change adapter settings” Option = A Network Connections window will open with the available connections. Depending on the connection the user wants to disable, right-click on the icon of the adapter and disable it. ' Network Connections 1 T™ &> » “f‘ Control Panel » Network and and Internet Intemet » Network Connections Organize v Disable this Disable this network network device device Diagnose this connection Rename this connection View status of this connection Change settings l:_ sirtel airtel.:." [. - Broadband Connection Broadband Connection E! EE Ethernet Ethernet. — —~n Networl Networl Si =2.l @7 @ Reatei (& Disable Rtanekfi Disable ]) Status Diagnose & Bridge Connections 8ridge Create Shortcut @ Oclete ©©® Rename Renome ©) Properties Figure 16.24: Disable an Ethernet Connection Module 16 Page 1948 Certified Cybersecurity Technician Copyright © by EG-Council EC-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting Update the Network Adapter Driver If the “network cable is unplugged” because of an outdated driver, then error occurred updating the network adapter driver will resolve the problem. To update the network adapter driver, follow the steps below. = Right-click on the Start Menu button and select Device Manager. Apps and Features Power Options Event Viewer System System Device Manager Network Connections Disk Management Computer Management Windows PowerShell Windows PowerShell Windows PowerShell (Admin) Task Manager Settings [ File Explorer Search Run Shut down orof sign out Desktop Figure 16.25: Go to “Device Manager” = |n the Device Manager, navigate to and click on Network adapters to expand the list of network adapters. Browse to the Ethernet adapter in use (Intel(R) Ethernet Connection (7) 1219-V). Right-click on the Ethernet adapter and select Update driver. A Device Manager - =) X File Action View Help | m DO e EmM P BmP EXG EXE v A& RODW-059 [~ RDDW-059 - » & Audio inputs and outputs , [0 Computer » e Disk drives » [ [l Display adapters » 3B Firmware > bvth belh Human Interface Devices ,» =@ @ IDE 10E ATA/ATAPI ATVATAPI controllers » 2 Keyboards » (@ ([ Mice and other pointing devices » [ Monitors 1 Network adapters < (7 Intel(R) Ethernet Connectiq (P (¥ Qualcomm Atheros ARSAE ARS4E (F (¥ VMware Virtual Ethernet A Disable device 0(0 VMware Virtual Ethemet A Etheret Uninstall Uninstall device device FP WAN Miniport (IKEv2) &¥ WAN Miniport (IP) (1P) Scan for hardware changes F&9 WAN Miniport (IPv6) (1IPv6) Properties Properties (F&P WAN Miniport (L2T7) (L2TP) P WAN Miniport (Network Monitor) (9 ¥£F WAN Miniport (PPPOE) ¥ WAN Miniport (PPTP) F&F WAN WAN Miniport Minipost ($STP) (SSTP) »» IR @@ Ports Ports (COM (COM &&LPT)LPT) N Dt miieie = Print svimiine Launches the Update Driver Wizard for the selected device. | Figure 16.26: Selecting the “Update driver” Option for “Network adapters” Module 16 Page 1949 Certified Cybersecurity Technician Copyright © by EC-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Network Troubleshooting = Select Search automatically for drivers. Windows will update to the latest driver for the Ethernet adapter. After the completion of this process, restart the computer. 0 Update Drivers - Intel(R) Ethernet Connection (7) 1219-V How do you want to search for drivers? —> Search automatically for drivers Windows will search your computer for the best available driver and install it on your device. —> Browse my computer for drivers Locate and install a driver manually. ‘ Cancel Figure 16.27 Selecting the option “Search automatically for drivers” Module 16 Page 1950 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited.