Hello,
Recently we moved our infrastructure to a new datacenter and immediately we started getting ipv6 connectivity issues. At first I was blaming the ISP, but after a lot of troubleshooting I think it might has something to do with the Mikrotik gateway (CCR1009-7G-1C-1S+).
We have a regular /64 where ::1 is the gateway of the ISP and our mikrotik is ::2. The ISP routes an additional /48 subnet over the provided /64 to ::2. On the mikrotik we split the /48 into several /64 and advertise it in different vlans. We have a static route to 2000::/3 set to go to the ISP ::1.
With the ipv6-addresses disabled in the vlans, we can ping ::1 and the rest of the internet from the mikrotik without packet-loss or whatsoever. But when we enable the vlan gateway addresses the mikrotik begins to struggle. 'Flows' of packet-loss occur from hosts to the internet and vice versa. (defining 'flows': connectivity is ok and abruptly gone for a 10-20 seconds).
I can see in the IPv6 neighbors that the ::1 is changing regularly to status=failed and the mac address disappearing. I have no clue why, because when I ping ::1 from the mikrotik seems to be ok.
When keeping a ping running from the mikrotik to ::1 the connections seems to be failing less often (but still too often).
Do you have any ideas about what is going on here or suggestions on how to troubleshoot further?
Kind regards,
Gino