Introduction to the Direct Attach Feature

The direct attach feature is a port configuration feature that supports VM-to-VM communication on a directly connected server that uses the Virtual Ethernet Port Aggregator (VEPA) feature on that server. Without VEPA and direct attach, a VM server must use a virtual Ethernet bridge or switch on the VM server to enable Ethernet communications between VMs. With VEPA, the VM server can rely on a directly connected switch to receive and reflect VM-to-VM messages between VMs on the same server.

The ExtremeXOS direct attach feature works with VEPA software on a VM server to intelligently forward unicast, flood, and broadcast traffic. Without direct attach, frames are never forwarded back out the same port on which they arrive. With direct attach, frames can be forwarded back out the ingress port, and VEPA software on the VM server ensures that the frames are forwarded appropriately.

For instructions on managing the Direct Attach feature, see Managing Direct Attach to Support VEPA.