We've never had a ring setup before and it's always been a hub-spoke type of design. Recently we've been fortunate enough to obtain our own dark fiber to create a ring of six main locations. We're looking at doing this by using OSPF to allow for multipathing, etc. My coworker and I recently took a 1 week course on OSPF but unfortunately it didn't dive deep enough for what I'm trying to accomplish.
Also, the two connections on each path (10Gb SFPs) are in a LACP group.
Here are a couple designs we're playing with...
http://dl.dropbox.com/u/95425426/OSPF_1.pdf
http://dl.dropbox.com/u/95425426/OSPF_2.pdf
What we're trying to accomplish:
Also, the two connections on each path (10Gb SFPs) are in a LACP group.
Here are a couple designs we're playing with...
http://dl.dropbox.com/u/95425426/OSPF_1.pdf
http://dl.dropbox.com/u/95425426/OSPF_2.pdf
What we're trying to accomplish:
- Full redundancy between sites. We are also using four-strands of fiber in each direction to achieve 20Gb/s and also redundancy within the optical equipment.
- We have a DR location that I plan on bringing up a vSphere cluster... needs to have the server vlan spanned to it for VMware SRM to function the best. (We don't want to have to mess with re-IPing everything during a failover).
- Not cause any loops
- Main site has the Internet for all sites, so the default route would have to go back to the main site.
- Main site also has MetroE connections that are not participating in the OSPF, but route through the main site to get to the other sites on the ring.
- Right now everything is in Area 0 because most of the sites are just a /24 for the users and I couldn't think of a good reason to make more than one area?
- We were debating about a /30 (Diagram 1) between the sites on the ring or put them all in the same vlan on a /24 (Diagram 2). I seem to remember for OSPF it talks via multicast which to me means it won't get past to the other locations if everything is a /30? We did do a test setup of the /30 ring and each segment has it's own DR/BDR selected.. so essentially my ring has 6 DR and BDR routers?
- If we put everything in a /24 vlan I would think there would be only one DR/BDR and all the sites would be able to talk to each other via multicast... not sure if this is better or not since you would also have more broadcast traffic, etc. Also, if we put all in the same vlan wouldn't we have spanning tree issues?
- We were seeing some weird problems with the /30 diagram where if I pulled one fiber the location would have no traffic for around a minutes and then it would finally 'notice' the other direction and start routing... in our class they mentioned turning off spanning tree on the OSPF ports and once I did that on all the routers it started working very fast for cutovers.