How many BGP peers are supported X670-48x?

[Kajetan_Staszki]

I wonder how many BGP peers can I connect to the switch? I have a BGP session to datacenter provider who gives as the default gateway for IPv4 and IPv6 via 2 separate BGP sessions. I have a whole bunch of loadbalancers (>30 machines) which I want to connect to the switch via BGP Each one needs to establish 2 sessions for IPv4 and IPv6 (restriction of BIRD).

How many BGP sessions are safe for this switch? I'm currently using OSPF for this purpose but I'd like to give BGP a try for some reasons.

[Kajetan_Staszki]

Thank you everybody for replies,

At this moment with a total of 14 peers bgp process shows nearly no load (<1%, with 3,5% peak). As for external route-reflector setup, I want to avoid it in order to keep the amount of hardware needed for network operation to minimum, that is fit as much as possible on central Extreme switches, which are hardly ever restarted and don't need as much maintenance as "software" bgp server.

[Chad_Smith1]

Kajetan,

Changing the timers increases the processing load on the switch. However, you also have a small number of routes. Maximum limits are usually best case scenarios. With the mixing and matching of IPv4 and IPv6 and changing the keep-alive it is difficult to determine your max. I would have to recommend you test it just to be on the safe side.

You are limited to a maximum of 64 BGP peer groups. I do not think that this will have an impact in your setup unless you need more groups than that.

[Frank]

Kajetan,

With this many bgp peers, would it perhaps make sense to run a "Route Server" or "Route Reflector"? Basically a central BIRD/Quagga server that everyone peers with? (See http://www.cisco.com/c/en/us/td/docs/ios/ios_xe/iproute_bgp/configuration/guide/2_xe/irg_xe_book/irg... and http://www.gossamer-threads.com/lists/quagga/users/11604)

Note: I may be totally off here; I'm just currently starting to read up on those things and it seemed as if it might be useful in this case. But as I said, I might be totally wrong 😉

[Kajetan_Staszki]

Thanks for pointing me to Release Notes. I've checked only the usual huge manual PDF file for firmware 15.5 which I'm running in the test enviroment and I could not find this information there.

I want to run quite short timers. Currently we use on-link public IPs on Loadbalancers provided by FreeBSD's CARP mechanism which detects trouble in just (AFAIR) 3 seconds. So let's say that I want BGP keepalive every 3 seconds and and hold-down after 10 seconds.

Number of routes should not be an issue. Each Loadbalancer will advertise only his single IPv4 /24 prefix and a single IPv6 /64 and a few Loadbalancers will advertise some longer prefixes during things like migration of services or for redundancy between datacenters. The only thing received from Datacenter is default gateway.

Of course I want to use peer groups. But does it change anything in terms of maximum number of peers?