[pkj]

>Running an all layer2 network requires devices that have large enough CAM tables to support all connected devices, many vendors newer full line rate cards were coming out with smaller CAM tables, as such layer2 simply wasn't an option in some cases.

Does this imply that mac forwarding tables(on switch) and arp cache(on hosts) need to have entries only for their immediate neighbours ?

Curious to know how much modified the host network stack is. Also, how do you provision a new server with the right IP ? Is this mechanism in L2 ?

>There are many other reasons that layer2 wasn't a good choice for us, and that layer3 makes a lot of sense. I'd be happy to discuss more of these as well.

I am sure people would find that very useful. Thanks for the excellent writeup !

[jimB0]

The last-hop switches facing the servers are layer 3 in the direction of the aggregation switches and layer 2 in the direction of the servers so ARP is handled normally and DHCP can be handled with standard DHCP-helper mechanisms. This allows the host networking stack to be vanilla (if you want it to be).