Help for someone not very sure of what they're doing.

Question

Hey,
We're a small film production company based in Shanghai and we're about to start production on the biggest project we've ever done and in preparation for the project we want to streamline our workflow into a much more manageable system, but none of us have any real experience with decent server set ups.
I have in my time worked with just a dedicated machine as a small server for shared documents etc, but as we work with HDV footage we're going to need something substantially better in order to handle a lot of processor intense stuff.
My question is, what do we need to get to set this up? Right now the office has a couple of imacs, a couple of power mac G5s and a bunch of macbook/macbook pros. We need something whereby HD footage can be edited by multiple machines but all kept in a central location that is also able to be accessed remotely (although we don't need HDV to be supported for this). I've been looking into Final Cut and OSX server to run the workflow end of things, but I'm not sure what we need in terms of hardware.
Anyone got any suggestions for where I start? Obviously I don't know if I've given enough info for you to reply, but if you get back to me with questions I can try and give you some more info.
Thanks

Answer 1

Storage is available as Direct Attached Storage (DAS), as Network Attached Storage (NAS), and Storage Area Network (SAN) storage.
DAS is direct, fast, and local and typically single-host; the disks are attached to host-based controllers.
NAS is the slower and distributed and multi-host option; the disks are attached to a Gigabit LAN.
SAN is the faster and distributed and multi-host option; the disks are attached to a Fibre Channel network.
NAS trades off lower costs for higher bit-error rates; the controllers and particularly the host have to deal with the communications errors that arise. This adds some overhead, and reduces the speeds.
SAN has higher costs and lower bit-error rates; the controllers and the host can go faster, as there are fewer communications errors expected. This is lower overhead, and helps maintain speed.
As for the physical connectivity, NAS uses Gigabit Ethernet. SAN uses Fibre Channel.
DAS can use SAS, SATA, SCSI, FireWire, or otherwise. (The embedded disks within an Xserve are SAS/SATA connections.) There are trade-offs here, too. And there are some vendors that sell DAS gear that can (if you add more bits from the vendor) be re-configured and re-used on a SAN, should you move from DAS to SAN.
Mac OS X Server is a basic piece of the puzzle; with any moderate- to large-scale Mac OS X configuration, you'll have some number of Mac OS X Server boxes. Mac OS X Server with Xsan allows the server to access SAN-based storage, particularly with multiple servers accessing the same pool of storage. Xsan is a way to coordinate and extend Mac OS X Server to operate in parallel with other Mac OS X Server boxes.
Add-on software is either not needed for DAS, or it's a driver or kext for the particular host-based storage controller.
Add-on software may be needed for NAS, or the NAS controller presents an AFS server.
For highest speed, the usual choice is DAS or SAN, and the decider there is the likelihood you'll need to access the storage from multiple servers at speed. DAS is typically single-host, where SAN is multi-host.
I'd suggest some more formal pre-sales or technical help here. You're headed for a whole lot of decisions, and the NAS and DAS and SAN differences are just one of many, many, many decisions and trade-offs that are involved with acquiring and configuring and running a server. Any sort of a server.