In my blog post I used a Perl one-liner to extract IP addresses from logs: 

journalctl --since "00:00" |  perl -lne '/((?:\d{1,3}\.){3}\d{1,3})/ &
+& print $1'

[download]
A tiny code but pretty useful.
Noi siamo quello che facciamo. -- L. Sciascia

In reply to Extract IP addresses by reisinge

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