After a configuring a VLAN and also after deleting VLAN, we can validate the configuration using Cisco IOS show commands. The command syntax is following:-
- Show vlan [ brief | id vlan-id | name vlan-name | summary]
- Brief – it displays one line for every VLAN with the name of VLAN, status, and ports.
- Id vlan-id – This parameter displays the information about a specific VLAN with VLAN ID number.
- name vlan-name – Display the information of a specific VLAN with the name of VLAN.
- Show interfaces [interface-id | vlan vlan-name | switchport]
- Interface-id – this is a valid interface id included a module, port numbers, and port channel. The port-channel range is between 1 to 6.
- Id vlan-id – This parameter displays the information about a specific VLAN with VLAN ID number. The range of VLAN id is 1 to 4096.
- switchport – This parameter displays the operational and administrative status of a switch port, including blocking of the port and port protection settings.
Now we are going to use the show VLAN command with a different parameter. The “show vlan name account” command output is not easy to understand. The figure below illustrates the output of this command.
The recommended command is “show vlan brief” and also “show vlan summary” These commands display the count of all configured VLANs. The output of the show vlan brief command illustrated in the figure below.
We can execute the show interfaces command with following parameters.
We can delete VLAN with “no vlan vlan-id” command in global configuration mode. For example, “ no vlan 10 “ in global configuration mode will delete VLAN 10 from switch Karak database. The ports of VLAN 10 is not the member of any VLAN now. You can verify it with “show vlan brief” command that VLAN 10 is no longer present in the vlan.dat file after using the no vlan 10 commands. Best practice before deleting VLAN is reassigning to all member ports to a different VLAN because any port that is not moved to an active VLAN are unable to communicate with other hosts after the deleting VLAN and until they are assigned to an active VLAN.
We can delete the entire vlan.dat file using “delete flash:vlan.dat” command in privileged EXEC. The abbreviated command is “delete vlan.dat”. We can also use this to delete a vlan.dat file if the file is stored in its default location. After executing this command and restarting the switch, the formerly configured VLANs are no longer present. This places the switch into its factory default condition for VLAN configurations.
Social engineering is a non-technical way for a criminal to collect information on a target. It is an art of gaining entrée to buildings, systems or data by exploiting human psychology, instead of breaking in or using technical hacking techniques. For example, instead of trying to find software vulnerability, a social engineer might call an […]
Security back hole can have an effect on web browsers. The web browser display pop-up promotion, collect identity information or installing adware, viruses, or spyware. A cybercriminal can hack a browser’s executable file, a browser’s components and plugins. Plugins A plugin is a software that acts as an add-on to a browser and installs extra functions in the browser. Plugins allow […]
Vishing Vishing is also phishing. It is using voice VoIP communication technology for fraud. The criminals’ spoof calls from legitimate sources using voice over IP (VoIP) technology. The victim can receive a recorded message that appears legitimate. Vishing works just like phishing but does not always occur over the internet and is carrying out using voice technology. Vishing […]
As I said in one of my earlier article that phishing is easy to execute and its required very little efforts therefore many cybercriminals use this method. Criminals sent fake emails, text messages and created a website looking authentic. They use email, messages, and website to steal personal and financial information from users. This is […]
In the previous article, I discussed malware including its types virus, worm, ransomware, trojan horses, logic bomb, backdoor, and rootkits. In this article, we should discuss malware types spyware, adware and scareware. Spyware A computer installs this software without the end-user knowledge and enables a criminal to get information about user’s computer activities. The activities […]
Email is a universal service using billions of peoples worldwide. It is one of the most popular services in the world but it is the highest vulnerability to the internet users. These e-mails are also known as “junk mail”, an unwanted email, the majority of an advertiser using these junk emails. However, the criminals send harmful […]
Malware, or malicious software, is a program or file that designed to disturb computer process and operation or gain entrée to the computer system, without the user’s knowledge or permission. Malware has become a common term used to explain all hostile or intrusive software computer viruses, worms, Trojan horses, ransomware, spyware, adware, scareware, and other […]
What is Trunks In telecommunications, the trunk is a link to carry multiple signals simultaneously and providing network access between two points. Its provide network access to many clients by sharing a set of lines or frequencies instead of providing them individually. This is similar to the structure of a tree with one trunk and many branches. Typically, trunks connect […]