Personally, I don't use regexen with IP addresses. There's a node that was written in 2002 that covers some of the pitfalls that you'll encounter. See:

Don't Use Regular Expressions to Parse IP Addresses!

While using regexen for server logfiles is OK, they can turn on you.

In reply to Re: regex for perl script by Khen1950fx
in thread regex for perl script by Anonymous Monk

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