When I try to traceroute to a remote ip, I get send: Operation not permitted When I stop iptables, traceroute works fine. So, I assume I need some ip rule for send. What would that rule be?

I did find a solution here http://forums.fedoraforum.org/showthread.php?t=112516, and I add it to my iptables, restart it, but then after a while CSF seems to block send again. Something overwrites that rule.

1 Answer 1


Found the solution:

Do you have CSF installed? If yes, open the config page for CSF and search the page for traceroute. There you'll see this message:

# Allow outgoing UDP ports

# To allow outgoing traceroute add 33434:33523 to this list

  • Thank you very much! adding CSF ports to outgoing traceroute solve this issue.
    – user294390
    Jun 16, 2015 at 2:16
  • 1
    Please note that in CSF you must add the port range for IPv6 as well if you want to perform a traceroute6 (UDP6_OUT) Oct 11, 2017 at 9:13
  • 2
    CSF == ConfigServer Security & Firewall configserver.com/cp/csf.html Jan 19, 2019 at 17:10
  • Where is the config page for CSF? Sep 27, 2020 at 8:00
  • If you are using cPanel / WHM, then search for ConfigServer Security & Firewall to find the config page for CSF.
    – David
    Apr 5, 2022 at 18:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.