MikroTik's IPv6 SLAAC client has a bug, when it received a RA packet with Interval advertisement field, it can't obtain an address correctly from the router.

The log on MikroTik shows like that:

22:01:50 radvd,debug received Router Advertisement on ether1 from <some mac>
22:01:50 radvd,debug   prefix: <some prefix> valid: 1800 preferred: 900
22:01:50 radvd,debug   unsupported option 7

So I'm submitted a patch which allows VyOS don't send Interval advertisement in RA packet.

e.g. the command line will be:

set service router-advert interface <some int> no-send-interval