10G links between serverfarms

DPodtikhov · ‎09-25-2009

Hello everybody

We are implementing reserve server farm (SERVERFARM2 at the picture) and we want to connect the farms via the 10G link. 10G is the requirement.

I have a server vlan and several clients vlans. Inter vlan routing is provided by 3750G LAN switches, servers are also connected to them at the moment.

I have attached the desirable scheme.

There will be about 8km distance between serverfarms. Main traffic will be database replication traffic between two serverfarms.

I don't know what is better, to interconnect serverfarms using layer 2 domain (in this case the reserve will be provided by spanning tree) or to connect them via layer 3 links (reserve will be provided by OSPF)?

I have chosen WS-C3750E-24TD+

Cisco X2-10GB-LR cards as server farm switches.

Will they handle 10Gbps of traffic on the routed layer 3 ports? Or 10Gbps speeds are real only at layer 2 links?

Joseph W. Doherty · ‎09-25-2009

"I don't know what is better, to interconnect serverfarms using layer 2 domain (in this case the reserve will be provided by spanning tree) or to connect them via layer 3 links (reserve will be provided by OSPF)? "

If routing is supported by the equipment, newer design practice generally uses L3. (NB: There will be a higher license cost to use OSPF on a 3570E, I believe. You also could route on just the 3570Es and use L2 only on your 3750Gs edge switches.)

"Will they handle 10Gbps of traffic on the routed layer 3 ports? Or 10Gbps speeds are real only at layer 2 links?"

Should be about the same performance as long as L3 is CEF switched in the hardware.

PS:

BTW, if you don't plan to stack the either the 3750G or 3750E switches, don't forget to consider the 3560 series; a little less expensive.

Also don't forget if and where stacked 3750Es not needed, the two 10G 4900 series switches are another option.

[edit]

PPS:

Also if you don't know, with the 3750 series you can mix 3750, 3750G and 3750E in the same stack. If you do this, the 3750Es give up Stackwise+ features but it's another less expensive option if a non-E stack would be suitable except for the need for 10G uplinks.