Comment 23 for bug 1404558

Short feedback on the "fix". I have 2 KVM based 14.04 64bit systems which were not affected by this bug UNTIL the 3.13.0-46.77 fix was release. On 1 of the 2 systems everything seems fine on the other IPv6 is not available directly after booting thus e.g. nginx can not bind to the configured IPv6 address.

on BOTH system I see this in kern.log:

Mar 3 07:14:56 sigma kernel: [ 8.449276] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready

but checking old kern.log file it has been this way for a long time so this is not the issue

on the system which works fine anyway I see this:

Mar 3 07:11:43 omega kernel: [ 21.556845] NFSD: starting 90-second grace period (net ffffffff81cdaa00)
Mar 3 07:11:44 omega kernel: [ 22.909888] random: nonblocking pool is initialized
Mar 3 07:11:45 omega kernel: [ 23.566021] ip_tables: (C) 2000-2006 Netfilter Core Team
Mar 3 07:11:45 omega kernel: [ 23.573073] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
Mar 3 07:11:45 omega kernel: [ 23.637709] ip6_tables: (C) 2000-2006 Netfilter Core Team

so after 23 seconds ip_tables and ip6_tables is running and IPv6 is working.

on the system where IPv6 remains unavailable for 2 minutes and thus nginx refuses to start I see this:

Mar 3 07:14:57 sigma kernel: [ 9.748740] NFSD: starting 90-second grace period (net ffffffff81cdaa00)
Mar 3 07:16:26 sigma kernel: [ 102.269932] ip_tables: (C) 2000-2006 Netfilter Core Team
Mar 3 07:16:26 sigma kernel: [ 102.279642] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
Mar 3 07:16:26 sigma kernel: [ 102.304003] ip6_tables: (C) 2000-2006 Netfilter Core Team
Mar 3 07:16:50 sigma kernel: [ 126.135981] perf samples too long (2621 > 2500), lowering kernel.perf_event_max_sample_rate to 50000
Mar 3 07:23:11 sigma kernel: [ 507.343615] perf samples too long (5025 > 5000), lowering kernel.perf_event_max_sample_rate to 25000
Mar 3 08:07:24 sigma kernel: [ 3159.511565] perf samples too long (10036 > 10000), lowering kernel.perf_event_max_sample_rate to 12500

This second system is an Intel(R) Xeon(R) CPU E5-2660 v3 @ 2.60GHz KVM based system with 12GB and 4 Cores, the first system which works fine is an Intel(R) Xeon(R) CPU E5-2670 v2 @ 2.50GHz based system with 8GB and 2 Cores.

As you can see it takes about 2 minutes until ip_tables as well as ip6_tables is starting on the second system. Which then causes nginx to not start up at all and having to restart it manually after IPv6 is available.

The perf samples too long error is also a new error I have not seen in the logs before. Unsure if it might be related to this problem or is related to changes made from 3.13.0-46.75 -> 3.13.0-46.76 a few days ago.