RSSAll Entries Tagged With: "Cisco Router"

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 […]

Troubleshoot Slip Secs Errors on Cisco Controller T1 Interfaces

We will find Slip Secs Errors on Controller T1 interfaces in Cisco Routers. If slips are present on the T1 line means there is a clocking problem from Telco provider. The Customer Premises Equipment (CPE) will need to synchronize to the clocking from the T1 provider (Telco). Cisco#show controllers t1 T1 0/0/0 is up. Applique type is Channelized T1 Cablelength is long 0db No alarms detected. alarm-trigger is not set Soaking time: 3, Clearance time: 10 AIS State:Clear LOS State:Clear LOF State:Clear Version info FPGA Rev: 08121917, FPGA Type: PRK4 Framing is ESF, Line Code is B8ZS, Clock Source is Line. CRC Threshold is 320. Reported from firmware is 320. Data in current interval (255 seconds elapsed): 0 Line Code Violations, 0 Path Code Violations 12 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins 0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, […]

How to upgrade Cisco Router IOS using TFTP Server

Prerequisites This document covers IOS up gradation step by step process on Cisco Router. The Router should be up and running whose image needs to be upgraded and this document not intended for password recovery.  You make sure that new IOS image supports hardware, software features, Router has enough Flash memory to run the image and other memory & processor related specifications. If you do sure, go to the SoftwareCenter in the Technical Support area at and use the Hardware-Software compatibility matrix to determine the version of software which is suited. Any IOS up gradation or backup process first we will need to have TFTP server. This can be downloaded from Internet. There are several versions of TFTP available free (Free TFTP can be downloaded from ) Step 1  a)     Copy from CD or Download the Cisco IOS software image to your workstation or PC. b)     Install the […]

How to create a Tunnel interface and configure between Cisco Routers

Create and Configure a Tunnel Interface on Cisco Router  You can create a Tunnel interface on Cisco Router and establish a Tunnel between two locations. Tunnel between two location Routers are useful for load sharing on WAN links or Resources. Below I will share the Tunnel configuration on Cisco Router at both ends to establish a tunnel. Create a Tunnel Interface on Cisco Router Cisco-Router(config)#interface tunnel ? <0-2147483647>  Tunnel interface number Cisco-Router(config)#interface tunnel Tunnel Configuration at A end Cisco Router: interface Tunnel100 description ***Tunnel to B location *** ip address keepalive 5 4 tunnel source tunnel destination ! interface Fastethernet 0/0 description *** Tunnel  Source Interface *** ip address secondary ip address ip accounting output-packets ip pim dense-mode ip route-cache flow ! Tunnel Configuration at B end Cisco Router: interface Tunnel104 description ***Tunnel to  A Location **** ip address keepalive […]

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 […]