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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

watch iptables counters

Terminal - watch iptables counters
watch -d -n 2 iptables -nvL
2014-02-23 16:35:03
User: xxdesmus
Functions: iptables watch
watch iptables counters

This will highlight (with a box over it) any changes since the last refresh.


There are 4 alternatives - vote for the best!

Terminal - Alternatives
watch --interval 0 'iptables -nvL | grep -v "0 0"'
2009-08-22 18:18:05
User: Code_Bleu
Functions: grep watch

This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

watch 'iptables -vL'
2009-03-20 14:49:12
User: alanr723
Functions: watch

Watch the number of packets/bytes coming through the firewall. Useful in setting up new iptables rules or chains. Use this output to reorder rules for efficiency.

while true; do iptables -nvL > /tmp/now; diff -U0 /tmp/prev /tmp/now > /tmp/diff; clear; cat /tmp/diff; mv /tmp/now /tmp/prev; slee p 1; done
2012-04-15 00:02:33
Functions: cat diff iptables mv

this alternative shows the differences as they occur so that they are made plain

Know a better way?

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