Just setup my first AVID ISIS with lots of assistance, so my opinion
may be full of balogna.
What I just don't get is why AVID creates three "virtual drives" which are three groups of four drives, each with a hot spare (in a 6 bay chassis running Windows Server 2008), and the 16th drive is an additional hot spare. So 32 TB becomes 22TB, and the max bandwidth is 300MB/sec, because of the way it's stripped. Now I understand that this gives some peace of mind in case of catostrophic failure, but RAID6 does exist on most of the host adaptor cards, and they would get such better performance instead of the three groups of 5 each with a hot spare. The host adaptor card in the Win server is an LSI MegaRAID.
I'm demo-ing a single chassis ISIS 5000 right now. It was configured 10Gb to a Force10 S25N switch. Our facility has an EditShare currently and also a MetaSAN system. My frustration with EditShare is the poor performance of Mac's using SMB. We do not have DAVE due to IT policy. I did not have high expectations of the ISIS but was impressed that the benchmark tests as well as Finder copies had similar to Windows performance close to 100MB/Sec. I was shocked when I connected a second 1Gb connection to the Mac and it instantly and almost magically went to 160MB/sec in the Blackmagic Speed Test. I have not seen this performance on a Mac unless using AFP with a 10Gb Myricom card on the EditShare. Unfortunately, I have not been able to get 10Gb to work on the ISIS. I direct connected a workstation in place of the Switch and got these error messages regarding write cache or something.
You mentioned the multiple RAID 5's. This system seems to load-balance across all RAID's in the system. So far performance seems good. I'd be interested to see how a multi-chassis system performs.
I'm not happy about the narrow switch options. We implemented our single chassis EditShare on an HP ProCurve with 8 10Gb ports with no restrictions so these narrow specs that AVID has is something I'm not used to. Our IT says that connecting to the house network will not be as easy as I thought. I was hoping to utilize DHCP, Active Directory accounts as well as giving ISIS connected machines access to the rest of the network without additional NIC's. Our dealer says that it's best to use the dual ports in a Mac Pro for the ISIS and add a SmallTree for the house network.