IPv6 not responding on some aliases (recent 8-stable)

[Marcin Cieslak]

>> Bjoern A. Zeeb <bzeeb-lists at lists.zabbadoz.net> wrote:
>> I initially thought it's a transport layer issue, since previously (before
>> I changed configuration) 30%-50% SSH connection attempts succeeded
>> (but prefix was wrong on the "primary" IPv6 address :1000).
>> Now I get no packets on receiving side at all for those "broken" IPv6 addresses.
>
> Talk to ywhomever is providing in front of you to
> 1) either relax nd6 table limits or
> 2) to route a /64 to your host to only have 1 entry in the neighbour table.
>
> That's most likely the problem given my crystal ball and experience.

Thank you for insightful analysis! 
Seems like this provider has some significant IPv6 takeup, which is
good news - sorry for hassle, but problems started after upgrade. 

I'll talk to my upstream then, thanks!

//Marcin