First, let me say I'm not an Ubuntu developer. Second, is this still a problem for you?
On a system running Precise, this seems to work for me: Linux yak 3.2.0-107-generic #148-Ubuntu SMP Mon Jul 18 20:22:08 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. >From 10.1.1.1 icmp_seq=1 Frag needed and DF set (mtu = 1500) --- 10.1.1.2 ping statistics --- 0 packets transmitted, 0 received, +1 errors ============================================================= Per route MTU is set to 800 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. >From 10.1.1.1 icmp_seq=1 Frag needed and DF set (mtu = 800) --- 10.1.1.2 ping statistics --- 0 packets transmitted, 0 received, +1 errors ============================================================= Per route MTU is set to 600 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. >From 10.1.1.1 icmp_seq=1 Frag needed and DF set (mtu = 600) --- 10.1.1.2 ping statistics --- 0 packets transmitted, 0 received, +1 errors ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. >From 10.1.1.1 icmp_seq=1 Frag needed and DF set (mtu = 1500) --- 10.1.1.2 ping statistics --- 0 packets transmitted, 0 received, +1 errors On a system running Trusty, it also seems to work: Linux tuna 3.13.0-93-generic #140-Ubuntu SMP Mon Jul 18 21:21:05 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=1500 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= Per route MTU is set to 800 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=800 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= Per route MTU is set to 600 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=600 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=1500 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms On Xenial, it also seems to work: Linux grape 4.4.0-34-generic #53-Ubuntu SMP Wed Jul 27 16:06:39 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=1500 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= Per route MTU is set to 800 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=800 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= Per route MTU is set to 600 PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=600 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ============================================================= No per route mtu entry PING 10.1.1.2 (10.1.1.2) 2000(2028) bytes of data. ping: local error: Message too long, mtu=1500 --- 10.1.1.2 ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1177507 Title: per route mtu settings are broken in linux kernel 3.2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1177507/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs