IPv6 Martians

[Eugene Grosbein]

29.08.2018 2:35, Dries Michiels wrote:

>> IPv6 Martians are blocked by forwarding code in 11-STABLE, but all this noise
>> fills kernel message buffer:
>>
>> cannot forward from :: to 2001:xyz:zxy::f00b nxt 58 received on vlan5 cannot
>> forward from :: to 2001:xyz:zxy::f00b nxt 58 received on vlan5 cannot
>> forward from :: to 2001:xyz:zxy::f00b nxt 58 received on vlan5 cannot
>> forward src fe80:10::yxz:a50f:fcb6:5f1e, dst 2001:xyz:zxy::f00b, nxt 58, rcvif
>> vlan4, outif vlan2 cannot forward src fe80:10::yxz:a50f:fcb6:5f1e, dst
>> 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::yxz:a50f:fc89:e1a0, dst 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif
>> vlan2 cannot forward src fe80:10::yxz:a50f:fc89:e1a0, dst
>> 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::268a:7ff:feeb:d250, dst 2001:xyz:zxy::d1, nxt 17, rcvif vlan4, outif
>> vlan2 cannot forward src fe80:10::yxz:a50f:fc8a:9024, dst
>> 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::yxz:a50f:fc8a:9024, dst 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif
>> vlan2 cannot forward src fe80:10::1, dst 2001:xyz:zxy::f00b, nxt 58, rcvif
>> vlan4, outif vlan4 cannot forward src fe80:10::1, dst 2001:xyz:zxy::f00b, nxt
>> 58, rcvif vlan4, outif vlan4 cannot forward src fe80:10::250:56ff:fe86:1b36,
>> dst 2001:xyz:zxy::d1, nxt 17, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::yxz:a50f:fc90:9d4, dst 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif
>> vlan2 cannot forward src fe80:10::yxz:a50f:fc90:9d4, dst 2001:xyz:zxy::f00b,
>> nxt 58, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::yxz:a50f:fc89:e1a0, dst 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif
>> vlan2 cannot forward src fe80:10::yxz:a50f:fc89:e1a0, dst
>> 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif vlan2 cannot forward src
>> fe80:10::yxz:a50f:fc89:e1a0, dst 2001:xyz:zxy::f00b, nxt 58, rcvif vlan4, outif
>> vlan2
>>
>> Dear subscribes, could you please prompt how to get rid of this noise?
>> So far I have not found appropriate sysctl for disabling this messages.
> 
> I can confirm the same issue on stable-11. 
> I just ignored it as I thought it was a badly coded client.
> Seems there is something else going on then.

As workaround, use sysctl net.inet6.ip6.log_interval=2147483647
This means "log this once per 68 years".