RSSAll Entries Tagged With: "Cisco Switch"

Cisco pipe Command Examples with Regular Expressions

We use the pipe (|) command more frequently on Cisco devices to get specific output of show & troubleshooting commands. Below are the available options for Pipe (|) command from Cisco ASR1002 Router. Cisco_Router#sh run | ? append   Append redirected output to URL (URLs supporting append operationonly) begin   Begin with the line that matches count  Count number of lines which match regexp exclud   eExclude lines that match format   Format the output using the specified spec file include   Include lines that match redirect  Redirect output to URL section   Filter a section of output tee    Copy output to URL Append option will send all output from the show command to be appended to a file already created at either a local (flash: disk:) or remote (ftp: tftp:) location. Example: The below command would copy the output off the show running-config command to an ftp server […]

How to trace physical interface with MAC/IP address in Cisco Devices

In this post I will explain the steps to find the client/end user computer connected physical interface in large Network environment with multiple Access Switches connecting to the core switches or routers. This will help you to trace and troubleshoot devices like a PC or a laptop or other end devices. This is not a difficult task but can certainly be time consuming. You can trace the physical interface by using MAC address or IP address. You can find the MAC address with “sh ip arp” command of particular IP address in gateway router. Let’s start with an IP address. Find out gateway router while checking traceroute to the IP address then login into second hop IP address from end and enter “sh ip arp X.X.X.X” command. C:\>tracert Tracing route to over a maximum of 30 hops 1     1 ms     1 ms     2 ms 2     1 ms    <1 ms    <1 […]

Difference between Stacking and Clustering on Cisco switches

Stacking Vs Clustering I covered the difference between Stacking and Clustering on Cisco Switches and it also applicable to all other vendor switches.   S.No Stacking Clustering 1 Stacking is a dedicated high performance but interconnecting desktop switches in single wiring closet, single point of authentication and management of desktop switches (single IP address) Clustering is a logical collection of switches independent of hardware interconnect method, single point of authentication and management with no physical boundary. 2 It isolated to the single wiring closet It extends beyond  wiring closet 3 It will not support for the legacy systems. It will support for the legacy systems. 4 It will support limited number of switches for stack It will support 16 switches per cluster 5 No flexibility in stacking design Admin chooses the cluster members. 6 Easily Scalable Not easily scalable as compared to stacking 7 Single IP address for management It […]

Switchport Port-Security Violation Options in Cisco Switch

Understand Swithport Port-Security Cisco layer 2 switch maintains the MAC address-table and it forwards a frames to destination based on MAC address table. We can enable a Switchport Port Security feature by allowing the specific Ethernet MAC address connected to the switch port. If any other MAC address tries to communicate through the same Switch port, port security will disable the port. Most of the time, network administrators configure the switch to send a SNMP trap to their network monitoring solution that the port’s disabled for security reasons. When using port security, you can prevent devices from accessing the network, which increases security. If any devices tried to connect to same switch port, there are three port security violation options available in Cisco Switch, based on your requirement you can enable any option for the switch port. There are three port security violation options are restrict, protect and shutdown, If […]

Difference between config.text and startup-config in Cisco Switch

Probably every one thinking  the config.text file contains the password definitions and Startup-config file contains the startup configuration, and config.text file saved in flash but the startup-config is saved in NVRAM. Above saved locations correct but the config.text file and startup-config are the same files with exactly same size.  I uploaded both config.text and startup-config to my TFTP server and tried to find differences between them. Both exactly the same and there no difference. Find the Config.text on Cisco Switch  Cisco-Switch#sh flash Directory of flash:/ 2 -rwx 3722814 Mar 07 1993 19:27:13 +00:00 c2950-i6k2l2q4-mz.121-22.EA14.bin 4 -rwx 1048 Mar 01 1993 01:41:49 +00:00 multiple-fs 5 -rwx 314 Mar 07 1993 19:34:02 +00:00 env_vars 6 -rwx 4635 Mar 01 1993 01:41:49 +00:00 config.text 7 drwx 832 Mar 01 1993 00:04:15 +00:00 html 21 -rwx 109 Mar 01 1993 00:04:17 +00:00 info 22 -rwx 109 Mar 01 1993 00:04:17 +00:00 info.ver 23 -rwx 45 Mar 01 1993 […]

Show / Find Users Currently Logged into Cisco Router/Switch

We can find or see the users currently logged into your Cisco Routers/Switches and also time, from which IP address users logged into Cisco Router/Switches. In Wide area networks are often very wide and installing or troubleshooting remote Routers often requires login from more than one physical location. It is simple to get a listing of the users logged into a Router and it useful to troubleshoot issues some times. Show Users command on Cisco Router/Switch To find the users logged into a Cisco Router/Switch, issue show users command: Cisco-Router#show users or Cisco-Router#sh users Show/Find Users Currently Logged into Cisco Router/Switch Find below output using show users command on Cisco Router or Switch: Cisco-Router#sh users Line       User       Host(s)                  Idle            Location 1 vty 0     John      24w2d 2 vty 1     John      24w2d 3 vty 2     Bijju      idle                    00:00:37 4 vty 3     Kanth     24w2d * 5 […]