https://regexr.com/
How to find IP the quick way and the exact way
https://www.regular-expressions.info/ip.html
Find IP (this will find 999.999.999.999 but you might not care
\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b
Below I was looking for 192.168.x.x
(192.168.)\d{1,3}\.\d{1,3}
Notes:
\b allows you to perform a "whole words only" search using a regular expression in the form of \bword\b. A "word character" is a character that can be used to form words. All characters that are not "word characters" are "non-word characters".
\d look for a digit
\d{1,3} look for between 1 to 3 digits
(192.168.) look for a group "192.168."
Example 1
Look for some thing with any character "."
that is 1 or more long "{1,}"
followed by a new line (\n)
followed by any number of white space "(\s+)"
followed by IP address (simple) "(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})"
(.{1,})(\n)(\s+)(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})
White space characters
\t (tab)
\n (newline)
\s (any white space)
\s+ (any number of white space)
Example 2
Looks for something(word) with any character 1 or more
any white space
IP address
(.{1,})(\s)(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})
Capture groups
(\n)(\t)
$1 = newline
$2 = tab
