Grab the first 3 octets of your ip addresses

ifconfig | awk -F: '/inet addr:/ { sub(/\.[^.]+$/, "", $2); if (!seen[$2]++ && $2 != "127.0.0") print $2 }'
For machines that have many ip blocks spanning different Class C's, this will show which ones.
Sample Output
[email protected]:~$ ifconfig | awk -F: '/inet addr:/ { sub(/\.[^.]+$/, "", $2); if (!seen[$2]++ && $2 != "127.0.0") print $2 }'

2016-09-01 14:02:43

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What Others Think

ifconfig | grep -i 'inet addr' | grep -v '127.0.0' | awk '{print $2}' | cut -d':' -f2 | cut -d'.' -f1,2,3
jamdev12 · 232 weeks and 6 days ago
@jamdev12 that wont remove duplicates it will print the same class c's, also that requires 2 greps, and awk, and 2 cut's.
chrismccoy · 229 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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