Tag: cli

Bringing Cisco IOS CLI to Linux CLI

There are few people on the globe who loves to work with Cisco and Linux via CLI. These people might have issues with trying to apply Bash/Vim syntax to IOS and vice versa. I’m certainly one of them. That’s why I can do the followng in my Bash:

$ show .bashrc | i return
[[ "$-" != *i* ]] && return
#     return 0
#     [[ -z $adir ]] && return 1
#   [[ $? -ne 0 ]] && return 1
#     [[ $? -ne 0 ]] && return 0
#   return 0

It’s very handy for checking Cisco configs, stored on a Unix machines, without inverting your mind out. In fact, if you are in rush and tried to apply IOS syntax to Bash, you won’t be distracted by an error message, but you’d get a result you reqired.

$ show samle_conf.cfg | i spanning-tree
spanning-tree mode rapid-pvst
spanning-tree etherchannel guard misconfig
spanning-tree extend system-id
spanning-tree pathcost method long
 spanning-tree portfast
 spanning-tree portfast
 spanning-tree portfast
spanning-tree bpduguard enable
...

It’s achieved very easily. You need to add some aliases to your ~/.bashrc file and relogin:

echo 'alias show="cat"' >> ~/.bashrc
echo 'alias i="grep --color"' >> ~/.bashrc

Finding repeating lines in a text file

Today I learned how to find all repeating lines in a text file. My goal was to find out all lines in a text which repeat more than once. A dirty, but efficient way is using sort(8) and uniq(8) combination (thanks to my boss for a pointer).

$ sort /var/log/messages | uniq -d

Do not try to pass a file directly to uniq(8) unless it is sorted. Uniq(8) can find only adjacent equal lines. If you think lines are randomly dispersed throughout the file, uniq will not return correct result. Be careful.