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Grep auth log and print ip of attackers

Terminal - Grep auth log and print ip of attackers
egrep 'Failed password for invalid' /var/log/secure | awk '{print $13}' | uniq
2009-10-04 18:08:13
Functions: awk egrep
Grep auth log and print ip of attackers

Work for me on CentOS, grep and print ip addresses of ssh bruteforce attempts


There is 1 alternative - vote for the best!

Terminal - Alternatives
grep Failed auth.log | rev | cut -d\ -f4 | rev | sort -u
2014-08-14 14:57:41
User: supradave
Functions: cut grep rev sort

Find the failed lines, reverse the output because I only see 3 indicators after the IP address, i.e. port, port#, ssh2 (in my file), cut to the 4th field (yes, you could awk '{print $4}'), reverse the output back to normal and then sort -u (for uniq, or sort | uniq).

Know a better way?

If you can do better, submit your command here.

What others think

The output should be sorted before being piped to uniq:

... | awk '{print $13}' | sort | uniq

Comment by xyz 312 weeks and 6 days ago

Your point of view

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