Pro Tools in an Ethernet SAN environment

[Nathaniel Cooper]

Eric,

As far as Ethernet networks go, unless your network is iSCSI based with a volume locking SAN software, Pro Tools will not recognize it as a valid audio drive.

Do not try the RAID 0 for Pro Tools. Any software striped RAID cannot be written to or read from by PT. Digidesign is very picky about what you can use for storage. Single LUN (hardware RAID, single drives, or multiple unstriped drives) initialized as HFS+ is what you need to present to PT.

Network wise, I’m very confident in saying my company is the go to company for networks with Pro Tools (https://www.studionetworksolutions.com/) Other than that, push pull to your network use locally attached, non-striped storage, and always run your back ups.

Nathaniel Cooper
Studio Network Solutions
818 209 1331

[Bob Zelin]

first off, let me say i know zilch about Pro Tools. always wanted to learn, but alas

REPLY – why do you assume that I know. I have built pro tools rooms with local storage, but not with SAN. Studio Network Solutions is the world leader in Pro Tools shared storage. Generic shared storage, like we do, DOES NOT WORK with Pro Tools (I don’t understand the technical reasons why) – but you can use a cheapo FW400 drive with Pro Tools to play back multiple tracks, but you can’t do this on an AFP network that is FASTER than a FW400 drive. Using iSCSI allows you to do this, and Small Tree has a specific product to allow this to happen –

“Prior to the introduction of GraniteSTOR abcSAN, professional audio studios facing bottleneck issues would need to purchase a storage system as well as a PCIe expander to improve their system’s performance,” said Corky Seeber, president of Small Tree. “With our iSCSI-based Ethernet storage system, which is faster than Firewire 800 and USB, Mac Pro users can now have a shared storage solution with RAID protection for all their data. That will improve workflow, thereby enabling the completion of projects on time and under budget.”

MORE REPLY – simple shared storage, and even complex shared storage like AVID Unity and Apple XSAN can do “push pull” with Pro Tools files (transfering them from local to shared), but cannot play them out – but iSCSI systems from companies like Small Tree, and Studio Network Solutions excel at this.

the facility that i installed my most recent ethernet SAN at wants to add a Pro Tools HD suite. the audio engineer that’s helping install the equipment says we need to use all 3 Digidesign PCIe cards in the Mac Pro. i’m wondering, if they use all the slots for Pro Tools, what do i do about storage?

REPLY – PT audio guys historically have been using, and have been very happy with FW400 drives. With that said, the MAC expansion chassis business has been developed initially specifically for Digidesign Pro Tools users – the most famous chassis, and the one repackaged by Digi for Pro Tools is the MAGMA expansion chassis. So a PT guy that says “I never heard of anyone using an expansion chassis” is an amateur, as this has been the case for MANY MANY years with Pro Tools. Need more slots – get an expansion chassis. But this won’t help you with playing back 48 audio tracks on an Apple AFP network !

1. this is a Nehalem Mac Pro, which has the built-in ethernet speed bug. i have an ethernet card ready for this computer, but if we need all 3 slots, we can’t use it.

REPLY – even with the Small Tree PEG1 card (which you MUST have with a Nehalem computer), you still can’t playout multiple tracks from Pro Tools (but you can from a local FW400 drive !). Use iSCSI – I am talking like I know what I am talking about – contact Small Tree on this.

2. i was thinking we could maybe put in 4 1TB hard drives and make a RAID-0 in Disk Utility (moving the boot drive to the second optical bay). that could act as the storage for Pro Tools. then set it to back up to the SAN every night since its RAID-0 and not 1 or 5, but…

REPLY – PT guys don’t need 4 terabytes of storage – never have.

3. how do i connect to the SAN? if i use one of the built-in ethernet ports, can i connect to the regular office network, which isnt gigabit and use that for pushing and pulling from the SAN?

REPLY – you aint’ gonna use “our” SAN for Pro Tools, no matter what. And yes, ethernet port 1 is for office, ethernet port 2 is for SAN (but not on a Nehalem, because you will disconnect after 60Mb/sec).

lastly. this isnt about the network, but just my ignorance with Pro Tools. they want a video output from the computer to send to a TV monitor in the recording room for VO and ADR. is there a way to output video from a Mac Pro without adding a capture card like the Intensity Pro? with all this i’m feeling like we need a PCIe expander. but i have no idea what a real Pro Tools studio uses.

REPLY – Digi now supports Blackmagic cards for output to monitors.

Bob Zelin

[Eric Hansen]

thanks for all the responses bob

i didnt know if the reason Pro Tools didn’t work with “our” SAN was because of bandwidth – that’s why i was thinking 4 drives in a RAID-0. i’m now thinking 2 drives in the Mac Pro in a RAID-1 could work. i’m worried about media redundancy since the files won’t be on the RAID-5 SAN. if FW400 drives work, this should work fine.

regarding the 60MB/s speed limit on the Nehalem Mac Pro – would a system connected using the “Automatic” settings (no flow control, no jumbo frames) stay below the 60MB/s speed limit? that’s why i was thinking about using the office network connection. the Pro Tools computer’s Port 1 would be configured as “Automatic”, as is the server’s connection to the office network (using Port 1, while the PEG6 card runs the 6 port agg). transferring files back to the SAN is important because the Pro Tools system will be used for sound design for the Final Cut editors. thus the sound designer will be constantly uploading new cuts to the SAN for editors to drop in. so the sound designer won’t be working from the SAN, but he will need to post up his cuts when he’s done. i can’t believe i’m trying to find a way to SLOW DOWN an ethernet network. maybe a USB ethernet adapter?

as far as video monitoring. would something like Matrox’s Dualhead2go work? it looks like Pro Tools will play video in a floating window, and we could move that floating window to the “third monitor” using a Dualhead2go. we have the standard Nvidia card in this Mac Pro.

thanks bob, as always

e

Eric Hansen – The Audio Visual Plumber – http://www.avplumber.com

[Bob Zelin]

Nathan has given you accurate information. You will not “jury rig” this up and get this to work. Use recommended Digidesign techniques and products for your video output. Do not use RAID0 for ProTools. “Our” SAN will not work with your application.

I know exactly what is happening here. Your client wants to spend no money (I don’t want to buy an expansion chassis !), and you are doing your best to make this work, with no money. Well, all I can say is “good luck” , and let us know what happens.

Bob Zelin

[Dave Klee]

Hey Eric, just wanted to chime in about trying an internal software RAID for Pro Tools. As others have said, it doesn’t work. I didn’t believe it last week, and actually tried to put two internal drives into a software RAID-1 (mirror) using Apple Disk Utility. I wanted the redundancy. But, it wasn’t recognized as a valid audio drive.

I’ve been told this is a hold over from the old days. Apparently, when Pro Tools began, standard file systems on both the Mac and PC were not capable of giving the reliable throughput that Pro Tools required for multi-track recording and playback. So, the people with Pro Tools essentially redesigned a file system that would meet their needs. Now that file systems have improved, there would be a lot of re-coding to get Pro Tools to support software RAIDs or file systems like Xsan. Sounded believable to me.

My half-ass solution is to put three drives inside the Mac Pro: one for the system (boot) drive, one for the “audio” recording drive, and one for a “backup” of the audio recording drive. All formatted as single, stand-alone drives. The audio drive clones on a schedule to the backup drive using Carbon Copy Cloner, a free backup utility for Mac that allows for scheduled drive backups regardless of whether a user is logged in (https://www.bombich.com/). Then, whenever a user does log in, the backup hard drive unmounts using a script — so people don’t accidentally record to the backup drive. This gives us some piece of mind with fairly minimal cost, and so far Carbon Copy Cloner has proven very reliable.

Good luck!

[Eric Hansen]

hey Dave

thanks for the suggestion on Carbon Copy Cloner. i think that’s the way we’re going to go. we’re going to access the SAN through the regular office ethernet, which is still gigabit but only 1500 MTU. hopefully that will slow it down enough to keep the ethernet port from disconnecting. since these guys are an island more or less, there wont be much file transferring going on.

thanks

e

Eric Hansen – The Audio Visual Plumber – http://www.avplumber.com

[Erik Guldager]

On what machines are you getting network disconnects?
I have a number of Nehalem 3GHz machines and none of them have issues with it.
ProTools is a beast, and the main reason that we still run a standard server setup together with “sneakernet” rather than a proper SAN model. But since we also use Nuendo that works with any kind of storage I think the time has come to do something about it.

Bob you wrote:”PT guys don’t need 4 terabytes of storage – never have. ” What do you base this on?
For a feature I will use between 500GB to a TB of local storage. I need a local fast backup (double the amount) and I might need to work on two films, hey presto that could be as much as 4 TB.
Even us audio folks use a lot of data these days just saying 🙂

[Eric Hansen]

Erik wrote: On what machines are you getting network disconnects?
I have a number of Nehalem 3GHz machines and none of them have issues with it.
ProTools is a beast, and the main reason that we still run a standard server setup together with “sneakernet” rather than a proper SAN model.

hey Erik. can you be more specific with “standard server setup”? the disconnects are a speed issue. if you are using the default connection settings, ie, no Jumbo Frames, then you probably won’t break the speed threshold that causes the disconnects. it actually took a few weeks after installation for this problem to show up. we were hitting the server pretty hard and it only occasionally disconnected. so i don’t think it happens EVERY TIME. but with my clients, who are used to Xsan, once is too many. according to Small Tree, the newest dev release of 10.6.3 has this bug fixed. hopefully the fix makes it to the release version.

to close this thread –

we have gone with 2 1TB drives in our Pro Tools Mac Pro. one is the Pro Tools scratch, and the other is a daily backup (Carbon Copy Cloner) of the scratch. any transfers with the SAN are done over the regular office network since all the PCIe slots have Pro Tools cards in them. we are thinking about getting a PCIe expander so we can add a video capture card for HD playback in the tracking room, and a Small-Tree card. but i bought a USB to DVI adapter to test video playback in the tracking room. so if that works, and a fix comes with 10.6.3, we probably wont get the PCIe expander.

e

Eric Hansen – The Audio Visual Plumber – http://www.avplumber.com

[Erik Guldager]

Standard file server on debian if i remember correctly, meaning no online storage, all work storage is local only. No Jumbo frames and no really time critical loads but quite a bit of large filetransfers.
I can see that I have some reading up to do to get accuainted before we venture forward.

[Caspian Brand]

With Studio Network Solutions iSCSI offerings, all that is required is your built in GbE port for Pro Tools. You don’t have to use up another PCI slot to gain real-time performance.

Pro Tools does not have high bandwidth requirements (64 tracks of 24bit / 48 kHz Audio is less than 10 Megabytes per second). It’s head seek time that Pro Tools is most finicky about.