how to extract ipv6 addresses from a file

Question

I want to grep ipv6 addresses in below format like 2a01:1388:120:720::1000 and 2b00:1188:210:9::2005

i use this to grep ipv4’s from a file

1.egrep '[[:digit:]]{1,3}.[[:digit:]]{1,3}.[[:digit:]]{1,3}.[[:digit:]]{1,3}' file

2.grep -E -o '(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?).(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)' file

Omit the -o if you want to see the entire line that matched.

Is there any similar regex for ipv6?

Possible duplicate of [Regular expression that matches valid IPv6 addresses](https://stackoverflow.com/questions/53497/regular-expression-that-matches-valid-ipv6-addresses) — Michael Hampton, Nov 21 '18 at 22:59
If you found the answer there, you may click the button which reads: "This solved my problem" — Michael Hampton, Nov 21 '18 at 23:41

score 2 · Answer 1 · edited Oct 25 '21 at 11:38

I found an answer in Regular expression that matches valid IPv6 addresses .

-bash-4.1$ egrep '(([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]).){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]).){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))' file

how to extract ipv6 addresses from a file

1 Answers1