The process goes like this:
Connectivity: Lets say, you have a backup host which is connected to SAN. There is VCB Framework installed on the same server so it becomes the VCB proxy as well, your ESX is also connected to SAN. make sure that the Data store LUN's are visible to the the VCB proxy server. And the tape library should also be visible. You can directly connect the Tape Library to the nackup server only when you dont want to share that device with any other server.
The ARCserve agent for Vmware will be installed by default, you just have to enable the feature.
once you trigger a backup job, the request 1st goes to the VCB component, from there to the ESX server. The VM's will be freezed for few milliseconds and keeps a copy of the snap shot files on the VCB Proxy server. And then ARCserve backs up those files. The Tape Library can be connected thru SAN to the backup server or Directly, no issues.
Let me know if you have further questions.
