cisco show running-configuration filter

Tired of having to scroll through your whole running-configuration just to read one line at the very end? Cisco has an in built command filter that allows you to specify more accurately what information you want from the running configurations, and mastering these commands not only makes you look like you know what you are doing ,they could save you lots of time and frustration having to look through irrelevant information.

There are mainly three widely used filter in the running config. BEGIN, EXCLUDE and INCLUDE. We can see this issuing the show running-configuration (sh run since we're trying to save time here) followed by the vertical bar key (|). We hit the question mark to see our options.

R1#sh run | ?
append Append redirected output to URL (URLs supporting append operation
only)
begin Begin with the line that matches
exclude Exclude lines that match
include Include lines that match
redirect Redirect output to URL
section Filter a section of output
tee Copy output to URL

The begin command filters through the configuration until it hits the first line that matches whatever word you put in after. Having an understanding of how lines are expressed in the configuration comes in handy when choosing what to type in.

As an example, here is the running-configuration of a router I am currently working on


R1#sh run
Building configuration...

Current configuration : 1238 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
!
resource policy
!
memory-size iomem 5
!
!
ip cef
no ip domain lookup
!
!
!
username R2 password 0 lanwan
!
!
!
interface Serial0/0
no ip address
encapsulation frame-relay
serial restart-delay 0
no dce-terminal-timing-enable
no frame-relay inverse-arp
frame-relay lmi-type ansi
!
interface Serial0/0.2 point-to-point
ip address 10.0.12.1 255.255.255.0
no cdp enable
frame-relay interface-dlci 102
!
interface Serial0/1
ip address 10.1.12.1 255.255.255.0
encapsulation ppp
serial restart-delay 0
no dce-terminal-timing-enable
ppp authentication chap
!
interface Serial0/2
no ip address
shutdown
serial restart-delay 0
no dce-terminal-timing-enable
!
interface Serial0/3
no ip address
shutdown
serial restart-delay 0
no dce-terminal-timing-enable
!
interface FastEthernet1/0
ip address 172.16.1.1 255.255.255.0
duplex auto
speed auto
!
ip http server
!
ip route 192.168.2.0 255.255.255.0 Serial0/0.2
!
!
no cdp run
!
control-plane
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
!
!
end

If we only wanted informatin on the configured static routes, using the begin command we can filter to the exact line.

R1#sh run | begin ip route
ip route 192.168.2.0 255.255.255.0 Serial0/0.2
!
!
no cdp run
!
control-plane
!
!
line con 0
exec-timeout 0 0
logging synchronous
line aux 0
line vty 0 4
!
!
end

and we see that this begins the display with the first line that has the words "ip route"

We can use the include command to only display lines that have the words "ip route"

R1#sh run | include ip route
ip route 192.168.2.0 255.255.255.0 Serial0/0.2

This is much more succint output and gives a much neater and pleasing to the eye display.

The Exclude command eliminates all the lines that have the word you put in. For example, if you wanted to remove all the lines that have the word "line".

R1#sh run | exclude line
Building configuration...

Current configuration : 1238 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
!
resource policy
!
memory-size iomem 5
!
!
ip cef
no ip domain lookup
!
!
!
username R2 password 0 lanwan
!
!
!
interface Serial0/0
no ip address
encapsulation frame-relay
serial restart-delay 0
no dce-terminal-timing-enable
no frame-relay inverse-arp
frame-relay lmi-type ansi
!
interface Serial0/0.2 point-to-point
ip address 10.0.12.1 255.255.255.0
no cdp enable
frame-relay interface-dlci 102
!
interface Serial0/1
ip address 10.1.12.1 255.255.255.0
encapsulation ppp
serial restart-delay 0
no dce-terminal-timing-enable
ppp authentication chap
!
interface Serial0/2
no ip address
shutdown
serial restart-delay 0
no dce-terminal-timing-enable
!
interface Serial0/3
no ip address
shutdown
serial restart-delay 0
no dce-terminal-timing-enable
!
interface FastEthernet1/0
ip address 172.16.1.1 255.255.255.0
duplex auto
speed auto
!
ip http server
!
ip route 192.168.2.0 255.255.255.0 Serial0/0.2
!
!
no cdp run
!
control-plane
!
!
exec-timeout 0 0
logging synchronous
!
!
end

Personally , I prefer the BEGIN and INCLUDE commands as they are more effective. Further more the output of the EXCLUDE command leaves some information hanging and that may be a bit confusing.