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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Quickly find a count of how many times invalid users have attempted to access your system

Terminal - Quickly find a count of how many times invalid users have attempted to access your system
gunzip -c /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log.0 | grep "Invalid user" | awk '{print $8;}' | sort | uniq -c | less
2009-03-03 04:26:57
User: eanx
Functions: awk cat grep gunzip sort uniq
Quickly find a count of how many times invalid users have attempted to access your system


There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

Try replacing less with wc -l to get the number of invalid users.

Comment by aperson 399 weeks ago

Use 'zcat' instead of 'gunzip -c' and there is no use of that 'grep' statement. Awk is grep on steroids, so take advantage of it.

zcat /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log | awk '/Invalid user/ {print $8;}' | sort | uniq -c | less
Comment by atoponce 399 weeks ago

somehow missed the '.0' on the second auth.log. you get the idea.

Comment by atoponce 399 weeks ago

You could also sort it again in the end :

zcat /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log | awk '/Invalid user/ {print $8;}' | sort | uniq -c | sort -n | less
Comment by raphink 399 weeks ago

zgrep "Invalid User" /var/log/auth.log* | awk '{print $8}' | sort | uniq -c | sort -nr

Much faster. (zgrep will happily grep through files which are not compressed.)

Comment by OJM 399 weeks ago

OJM, you had a typo (User instead of user), so yours is:

zgrep "Invalid user" /var/log/auth.log* | awk '{print $8}' | sort | uniq -c | sort -nr | less

Also, you might want to look for times when legit users failed to login:

zgrep "Failed password" /var/log/auth.log* | awk '{print $9}' | sort | uniq -c | sort -nr | less

Comment by dbart 398 weeks and 6 days ago

Your point of view

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