Public bug reported: My Ubuntu 20.04 smokeping setup was configured with binary name fping6, and smokeping 2.7.3-2 which always uses -6.
Using fping 4.2-1 on Ubuntu 20.04 the fping6-probes from smokeping stopped working. Using fping 4.0-6 on Ubuntu 18.04 the fping6-probe works as expected. After some digging, it turns out fping6 and -6 is broken, the program will exit with 'fping6: can't specify both -4 and -6' root@probe:~# fping6 -6 ipv6.google.com fping6: can't specify both -4 and -6 fping is working fine, as expected root@probe:~# fping -6 ipv6.google.com ipv6.google.com is alive --- root@probe:~# lsb_release -rd Description: Ubuntu 20.04 LTS Release: 20.04 root@probe:~# apt-cache policy fping fping: Installed: 4.2-1 Candidate: 4.2-1 Version table: *** 4.2-1 500 500 http://ch.archive.ubuntu.com/ubuntu focal/universe amd64 Packages 100 /var/lib/dpkg/status ** Affects: fping (Ubuntu) Importance: Undecided Status: New ** Affects: fping (Debian) Importance: Unknown Status: Unknown -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1875242 Title: Do not fail if using fping6 with -6 flag To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/fping/+bug/1875242/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs