Anyone using Network Attached Storage devices (NAS)?

Hard drives are like paychecks. No matter how big it is, I use every bit.
I'm curious about NAS drives with a gigabit ethernet interface. Is anyone using such a device for digitizing HDV footage over a network with FCP? I'm considering the WD MyBook World Edition drive. I know from the data sheet that it will show up on the Mac desktop under shared drives, but will it show up as a scratch drive in FCP?
Any comments would be appreciated.
Chris.

Try to use locally mounted storage as the operation is simpler, and avoid the Mybooks because they don't come with a fan.



www.strypesinpost.com

I have a ReadyNAS but it's nowhere near fast enough for real time video use in my experience. I just use it for backups and sharing files that I need to have accessible from multiple machines (generally not video because I only work with video on one machine). For those purposes, it works great.

The problem with network-attached storage isn't that it's inherently too slow ? gigabit can yield 100 megabytes per second if what's on the other end can keep up, after all. It's that with all the protocol layers in between the application and the hard drives, getting sustained-rate reads or writes is nearly impossible. Even a really good storage array, mounted via a really good protocol, will periodically and for absolutely no reason lag out on you for a fraction of a second, causing dropped frames. On playback this is annoying as hell. On didge, it's a start-over catastrophe.

The thing people sometimes forget is that even when video doesn't require high data rates, it still requires guaranteed data rates. It's a real-time application, after all. Since desktop operating systems don't do hard-real-time I/O, the customary way to satisfy this requirement is to give the system ten or twenty or a hundred times more I/O bandwidth than it needs, and to rely on the kernel's in-memory I/O cache to pick up the slack. Due to the way NAS works at a protocol layer, that's not possible, so NAS can never be 100 percent reliable.

That's what iSCSI hopes to address. It runs over gigabit Ethernet ? which, just for perspective, is faster than Firewire 800 but considerably slower than eSATA and much, much slower than Fibre Channel ? but it doesn't go through the various network protocol layers that network-attached storage uses. Which is great in principle, but the lack of a built-in Mac OS X iSCSI initiator (the little bit of software that has to run on the workstation) and the appalling unreliability of third-party initiators for the Mac makes it a complete non-starter right now.

Plus, iSCSI is largely a solution in search of a problem in our market. Like I said, it's faster than Firewire 800, but only marginally so ? a nominal gigabit versus 800 megabits ? and it's massively slower than Fibre Channel. Drop a thousand-dollar Fibre Channel board in your Mac Pro and you've got sixteen gigabits of bandwidth instantly, no mucking about with software. The only advantage of iSCSI is that it uses inexpensive copper cabling instead of optical fiber, but installing fiber's not that much more expensive than installing copper, so if you need to have guys pull new cable for you anyway, you might as well get the good stuff. Besides, in a lot of cases the interconnect between workstation and storage fabric isn't that big a deal, because both the workstations and the storage (and the switches for the storage) are all in the same racks in the tape room anyway.

There's definitely room in the market for something that's functionally equivalent to Fibre Channel ? high bandwidth, robust software support, extensive networking capabilities ? at the lower end. NAS will never be it, unless the way network storage is implemented in software is completely refactored. iSCSI is a move in the right direction, but it's simply not there yet.

So bottom line? Stick with Firewire drives. Either really good Firewire drives, or really cheap Firewire drives but twice or three times as many of them.

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I'm considering the WD MyBook World Edition drive.

No offense...but the whole "WD MyBook" series is JUNK IMHO. Not even worth plugging in IMHO. Very poorly constructed - not for industrial A/V use (plastic casing w/no fan).

We use an Ethernet RAID setup but don't digitize HDV...we digitize from DVCProHD and DigiBeta decks to Prores via Kona 3 cards (almost totally phased out DigiBeta - almost completely HD now).

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The problem with network-attached storage isn't that it's inherently too slow

??? Not seeing THAT at all. We wouldn't have installed it if were "inherently slow". Our 32 TB Ethernet system flys pretty well - no speed issues at all with 5 BUSY FCP stations working off of it at the same time. The only issue we have is the switch dropping connections every once in a while. The Speed ROCKS.

If you are not in a massive multi-user situation, I nice fat RAID tower (eSATA / FW800) with replacable drives (RAID 5) is my suggestion. I would also have a fat CalDigit VR @ RAID 1 for backup protection. You can NEVER be too careful with your data. No time to be cheap when dealing with media.

When life gives you dilemmas...make dilemmanade.

>We wouldn't have installed it if were "inherently slow".

There's a NAS (network attached storage) and there's a SAN (storage area network). To put it simply, you can run an edit system off GigE. Editshare does it, but that's really not your run-of-the-mill store bought NAS drives.

Now, when a NAS goes wrong... I had a gig once where we had this NAS RAID that stores all the tapeless footage, and editing was done in the internal RAID. Then they ran out out of space and started editing off the NAS. It was largely okay, especially since we weren't going out to tape and we were working of XDCAM EX, which uses bandwidth in the same ballpark as HDV and DV. Then, I tried rendering something in After Effects, and occasionally the media goes offline. And sometimes I couldn't save the project file, and there was once FCP crashed and the project file got corrupted and I had to dig into the autosave vault...



www.strypesinpost.com

NAS as a technology isn't inherently slow, but from what I've seen, all the cheap consumer-level NAS devices (which is what it sounds like Chris was talking about) are slow. I've never seen one come close to maxing out either the capacity of the network link or the theoretical throughput of the drives. They aren't designed to be high speed storage systems. If you want that, you need to spend more.