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Extract ip addresses with sed

Terminal - Extract ip addresses with sed
sed -n 's/\([0-9]\{1,3\}\.\)\{3\}[0-9]\{1,3\}/\nip&\n/gp' ips.txt | grep ip | sed 's/ip//'| sort | uniq
2010-05-23 11:26:32
User: rubenmoran
Functions: grep sed sort
Extract ip addresses with sed

Extracts ip addressess from file using sed. Uses a tag(ip) to grep the IP lines after extracting. Must be a way to just output regex matched on sed.


There are 2 alternatives - vote for the best!

Terminal - Alternatives
sed -n 's/.*\(\(\(^\| \)[0-9]\{1,3\}\.\)\{1\}\([0-9]\{1,3\}\.\)\{2\}[0-9]\{1,3\}\) .*/\1/gp'
2014-01-29 23:18:14
User: smkr
Functions: sed
Tags: sed ip address

looks for IPs at the beginning of the line or prefixed by a space

Know a better way?

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What others think

in before ipv6.

Comment by kaedenn 287 weeks and 3 days ago

You could just use grep to extract the ips. The -o option will make it do what you want to do.

grep -Eo '([0-9]{1,3}\.){3}[0-9]{1,3}' ips | sort | uniq
Comment by eightmillion 287 weeks and 3 days ago

Your point of view

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