Question about SANs and their performance
Posted on 2013-01-31
I'm new to SANs, but we're getting a iSCSI SAN installed at my office, and I'm just curious about a few things:
First, I understand the SAN is faster as far as drive performance than the storage in the local host (i.e. 24 drives in the SAN vs 4 drives in the local host), and I understand the benefit not just in performance of the drives, but in redundancy/resiliency as well. HOWEVER, what i'm concerned about (or maybe just don't understand), is with the drives in the local storage, they're connected via SAS, SCSI, SATA, or whatever option directly to the board. Whereas the SAN only has a few ISCSI gigabit connections between SAN and each ESXi host (we use vmware). Isn't the connection between the SAN and the host going to be a much bigger bottleneck than local storage speed? Wouldn't a single SATA drive connected directly to the local controller on the host be faster than a 60 disk SAN connected via a few gigabit ISCSI adapters?