Hi guys Any thoughts on the question I posted 3 weeks ago? I'm sure it can be done in something as flexible as Bird is. Just don't know how... Thanks! Michael On 28/02/14 15:49, Michael Ludvig wrote:
Hi
Short version: Can I assign different priorities (metrics?) to the same route inserted by Bird into different routing tables?
Long version: I've got a main office router with these uplinks:
- 1x SDSL with BGP, receives national routes - 1x ADSL with OSPF Cisco modem that advertises default route - 2x OpenVPN tunnel to our Datacentre (one over each physical connection) with OSPF that's primarily for internal nets.
The SDSL and Datacentre are with the same ISP and I can propagate our DMZ subnets over BGP from either location.
Then I've got two routing tables - one for internal LAN and one for DMZ which has different rules.
In normal circumstances the LAN traffic goes out over ADSL unless there is a better route learnt from BGP in which case it'd go out over SDSL. The DMZ traffic (public IPs) always goes out over SDSL, and the DMZ routing table has a static default rule in that sense.
Now if SDSL goes down - as it did yesterday after a fibre cut down the road... - all LAN traffic goes out over ADSL, that's good - DMZ subnet advertised from DC router over BGP and incoming traffic arrives over the OpenVPN tunnel (which still works over ADSL). - all DMZ egress is blocked though until I replace the default route in DMZ routing table to go via the tunnel to datacentre and from there to the internet.
If ADSL goes down... - LAN traffic is restricted to BGP learned routes (national traffic) until I add a static default route via SDSL - DMZ is fine
What I want is an automatic fail over for both LAN and DMZ if any one of the links fails.
My idea is to advertise a default route over all the uplinks and for the LAN routing table use them in this order of preference: 1. ADSL (OSPF), 2. SDSL (BGP), 3. one of the tunnels (unlikely if both physical links are down) For DMZ routing table do this order: 1. SDSL (BGP), 2. tunnel over ADSL (OSPF), 3. plain ADSL (OSPF)
I know I can manage different routing tables from Bird but how do I assign different priorities (metrics?) for the same route going into different tables?
Thanks!
Michael