Does anyone have a working configuration for GRE6 they can share?
Yours hopefully…
In communication with my reseller, the ever-helpful Mike Everest at Duxtel (http://www.duxtel.com.au - recommended!), the following popped back from Mikrotik:
Currently you cannot make tunnel to link local addresses. local and remote address should be global. We will fix this problem in the future.
And of course I was using link local addresses. Sigh.
Anyway, for those who would like to see a working configuration, here is one, with documentation prefix used for all addressing.
There is a direct link from ether5 on Router A to ether1 on Router B.
On Router A:
/interface gre6 add name=gre6_1 local-address=2001:db8:100::1 remote-address=2001:db8:100::2 keepalive=10
/ipv6 address add address=2001:db8:100::1/126 interface=ether5
/ipv6 address add address=2001:db8:100::5/126 interface=gre6_1
On Router B:
/interface gre6 add name=gre6_1 local-address=2001:db8:100::2 remote-address=2001:db8:100::1 keepalive=10
/ipv6 address add address=2001:db8:100::2/126 interface=ether1
/ipv6 address add address=2001:db8:100::6/126 interface=gre6_1
… in other words, it works exactly like IPv4 
As long as you don’t use link local addresses.
HOWEVER: The gateway shows up as “unreachable” (not in the flags, but in the detail from "ipv6 route print detail) regardless of the fact that all the IPv6 addresses involved are pingable, and that I can (eg) ssh across the tunnel. Possibly for this reason. OSPFv3 doesn’t work across the tunnel.
If anyone is working with GRE6 and has OSPFv3 working, I’d love to see your configs.
Regards, K.
Bump
Can anyone help me with OSPFv3 over this GRE6 tunnel? Anyone? MikroTik?
Regards, K.
HOWEVER: The gateway shows up as “unreachable” (not in the flags, but in the detail from "ipv6 route print detail) regardless of the fact that all the IPv6 addresses involved are pingable, and that I can (eg) ssh across the tunnel. Possibly for this reason. OSPFv3 doesn’t work across the tunnel.
[admin@v6test] /routing ospf-v3 interface> /ipv6 route print detail
Flags: X - disabled, A - active, D - dynamic, C - connect, S - static, r - rip, o - ospf, b - bgp, U - unreachable
...
1 ADC dst-address=fdae:adad:45d3:99::4/126 gateway=gre6_1
gateway-status=gre6_1 unreachable distance=0 scope=10
What does “gateway-status=gre6_1” mean? And why is it “unreachable” in the detail but not the flags? And above all, why is it “unreachable” when this works:
[admin@v6test] /routing ospf-v3 interface> /ping fdae:adad:45d3:99::5
HOST SIZE TTL TIME STATUS
fdae:adad:45d3:99::5 56 64 0ms echo reply
fdae:adad:45d3:99::5 56 64 0ms echo reply
sent=2 received=2 packet-loss=0% min-rtt=0ms avg-rtt=0ms max-rtt=0ms
Note that fdae:adad:45d3:99::5 is the address on the GRE6 interface at the other end of the tunnel.
It turned out that the interface on one of the routers DID NOT HAVE A LINK LOCAL ADDRESS. WTF?!?
I rebooted the router and the interface magically discovered a link local address. A bit of googling subsequently suggested that when an interface is split off from a master port, the newly independent interface will not have a link local address until after a reboot. I had started with a default config and taken ether5 off a master port.
OSPFv3 is working.
MikroTik - a reboot should not be required for a configuration change to work. And if it is unavoidable, then the relevant command should issue a clear statement that a reboot is required.
Regards, K.
OSPFv3 doesn’t work across GRE6 in my case even after reboot in Release 6.7 and 6.8rc1
They don’t see each other broadcast wise somehow.