I'm new to BGP - so this is certainly a learning exercise. I'm moving away from PA space provided on 2 routed uplinks to having my own IP space and multi-homing my transit.
To begin with, there will only be a single transit provider - and they have provided 2 RJ45 cable drops with a different /30 VLAN on each - to go to each of my Juniper EX3200 switches.
I only intend to take default routes for now - and in the mean time, I need to continue to use the routed uplinks and PA space - whilst maintaining another routing table for the new BGP gateway/network.
There is 2x uplinks (ge-0/0/0 and ge-0/0/1) on which my WAN glue block VLAN resides (
vlan4000). VRRP runs on this VLAN and all my IP's are routed from my provider to this virtual IP. Then internal routes are direct over VLAN L3 interfaces. The gateway IP (ie. my provider's router virtual IP) in
vlan4000 acts as my default route.
So I'm aware that I'll likely need to run two routing tables (VRFs) to separate the BGP IPs from the "other" IPs - and maybe do some filter based forwarding for selecting the right gateway.
I've been doing some fairly extensive reading of both,
To get a good understanding of the config required.
From my (limited) understanding thus far, I think I need to ...
- Bring up a BGP session with my transit provider
- Announce my IP block over my ASN
- Route the BGP IP block over that specific interface
- Form some kind of failure/HA between the two EX3200's so that a single failure doesn't drop the BGP session.
What I'm essentially unsure of is how the two EX3200's bring up their BGP sessions. As each have their own IPs (router-ids) in two separate VLANs - this looks to be two separate BGP sessions - and I'll need to conditionally route between each BGP default gateway if either goes down?
Has anyone got any example configurations of where to begin?