Your question is not very specific about WHAT software exactly you are talking about. If you mean "path failover" software, then the answer is NO. The failover agent must be on the host connected to its storage to control failover due to a bad HBA in the server.
If you mean SAN management software, then the answer is maybe. It depends on the vendor. Some vendors use "out-of-band" management for the storage arrays meaning a non-SAN connected server can "talk" to the array via its IP connected service processor. Other vendors require a server connected to the storage "in-band" over Fibre in order to issue commands to the array. Most let you do both or either.
If what you mean is virtualization type control, then an agent MAY be required on the application server. If the virtualization method is "in-band", meaning all requests go through the Fibre to a server front ending at a disk, then it may not need an agent. Again, depending on the vendor. Most "out-of-band" virtualization engines require either an intelligent HBA or an agent on the host.
So I guess my answer is the same one you would get if you asked any consultant. "It depends."
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This was first published in May 2002