Do you want to match lines with IP addresses that start with a comment?

grep '^#.*(?:[0-9]{1,3}\.){3}[0-9]{1,3}'

If you want you can 'trap' the IP address and just print that as well. Or did I miss the question?

--
“For the Present is the point at which time touches eternity.” - CS Lewis

In reply to Re: Seeker of Regex Wisdom (strings which don't form specific patterns) by KurtSchwind
in thread Seeker of Regex Wisdom (strings which don't form specific patterns) by ilcylic

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