Promise RAID5 connected by Firewire 800 to 3 year old iMac stopped working.  What should I replace it with?

computerlarry used Ask the Experts™
Mac user.
User had an old, no longer supported Promise RAID5 that had a drive stop working.
I inserted a replacement, but after 3 days the RAID didn't rebuild.
I pulled the new drive, but even though I was able to see the folders, no files could be accessed.
I called Promise.
Because the RAID was an older model, Promise had no Promise software was able to run on any Mac to do diagnostics.  They told me to find a backup, attach the drive to a Windows Machine, and only use it with Windows.

This is a disappointment.  I had a backup on BackBlaze, but it takes days to recover 2 TB

I need to choose between:
  • Finding an old Mac that will run the old Promise software, reformatting the Pegasus RAID 5, and assuming that the error was a one-show
  • Buying a new Pegasus 2  Thunderbolt - connected unit
  • Buying a CRU RAID one, and connecting it with a Thunderbolt to Firewire 800 connector, or else USB 3

User has a collection of Videos that they want to keep on a RAID.
They do not add videos very often, and may do some simple editing from time to time.

I realize that the RAID 1 would allow them to pull a drive out for safe keeping, and then rebuild the mirror.
I am wondering if CRU unit with USB 3 connected directly to a 3 year old iMac would have the throughput necessary to play Quicktime MOV files

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Top Expert 2016
USB3 is a lot faster than firewire 800,  I think it is time for a storage update
nappy_dThere are a 1000 ways to skin the technology cat.
Do you have the installer for the Older Mac OS?

If so, download a trial of VMWare Fusion and spin up a virtual machine.

Connect the raid drive and you should get a prompt asking where to connect the drive.

Select the virtual machine and if the volume is in good order, your data should appear.

***Note*** you should replace that failed drive. Due to the age of the unit your other drives could be failing and operating only on the parity is a risk because if on more drive fails all your data will be lost forever.
WakeupSpecialist 1
CRU makes some decent products.  How much space are they needing per say?  USB 3 is great if the Mac supports USB 3 as well?

Otherwise it may be slower if the Mac does not have USB 3 support.
That Raid 1 unit by CRU will support firewire 800, USB 3 and eSATA.

So they have options.

So the other question is are you able to recover the data to be able to do anything with the data (move to another unit etc).  

You are talking about abandoning Raid 5 for Raid 1.  So you won't necessarily have Parity if both drives in the Raid 1 fails.  However if you teach your client to have a 3rd drive as a spare to rebuild as often as they need, they can take that 3rd drive offsite, (safe, vault, lockbox etc) and have one located elsewhere in case of theft or fire (acts of god) etc.  Just that they will need to bring that 3rd drive back in to update/rebuild the Raid every so often.  

The RTX unit that I linked to from CRU is pretty nice.  It will rebuild to a Tray free bay, meaning all you need is just the drive (raw) no tray  needed.  It will rebuild from top bay to bottom, or bottom to top.  Has built in fan and hardware monitoring for the unit, in case of drive or fan failure.  Also it is standalone, you don't need it to be connected to a computer if you just want to rebuild from one drive to another.  You can also continue to use it if you pull one of the drives out and break the raid and insert a new drive and rebuild.  I love that unit.

And if the client prefers a bay with trays for some sense of protection on the drives, they do have units that work exactly like it but with trays.
Both tray free and tray bays have the ability to lock with a key as well for some easy protection.  But obviously theft, someone can take the whole unit.
Tray unit.  

They do also have encrypted units if needed.
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WakeupSpecialist 1
Also if you are still interested in running RAID 5, CRU has a 4 bay Raid unit as well.

Downfall is no offsite backup.


How is Drobo?
Top Expert 2016
drobo's are very good and you can mix and match drives.. pricey though
2 TB fits on a single drive.  RAID is not necessary.  It probably would be cheaper to get 2 drives and just duplicate the data manually, basically have a local backup in addition to the offsite backup with Backblaze.  That would allow you to recover in hours instead of days.  If you want speed, then get a smaller SSD for more recent files, and keep everything else on the slower disks.  You could even get a 2 TB SSD if you want it all available.

The point of RAID is for larger storage, faster access to data and uptime.  RAID isn't doing its job in this case.  2 TB is not really larger, so you don't need RAID.  SSDs are faster, so you don't need RAID.  The cheap RAID is now down, so your RAID isn't keeping uptime.  Just get 2 separate disks and just copy the data.  It will be cheaper, and probably more reliable than these low end RAIDs.  A 2TB SSD is around $450 now.  For $600, you can get 1 SSD and 1 HD for backup.  If one fails, just buy another.
WakeupSpecialist 1
Drobo units are decent when they work.  They have similar units to Cru.  I've had first hand experience with Cru's outstanding support.  Live USA tech support.  They will over warranty the unit.  Units might state a 3 year warranty.  But they go above and beyond.  Supporting their units being the 3 years in most cases.  They will send out a unit to replace a failed one before you send yours in.  If you are near their locations they will allow you to test drive and walk in for services, parts, power supplies, trays, fans, keys and much more.  They will also ship your some of those items for free if needed.  I can't say the same for drobo.
WakeupSpecialist 1
It really probably depends on the client and how easy it is or hard it is for them to use.  Think about the long run and what you are willing to support.

Serial makes some good suggestions. But there's no easy way to swap the drives without opening up the computer or putting the drives into external enclosures.  I haven't used his suggested software, so not sure if the customer is willing to learn how to use it, and would be able to keep the backups updated.  The convenience of a hotswapable raid 1 is that the drives are automatically synchronized and you can remove one of the drives one can fail and the user will remain up and running.  If you run just one single drive and it fails on the fly you will have to hope that the latests backup the client made is recent enough.  How often will they need to backup their data?  With that 3rd drive in rotation the client can keep swapping that 3rd drive to rebuild monthly, weekly, daily and easy really easy to just swap out at any time.  You can also rebuild and still use the computer and access the data at the same time.  

You'll want to find out what is convenient for the customer.
User had an old, no longer supported Promise RAID5 that had a drive stop working.
Well, there's your major problem.  The user should have purchased a replacement ahead of the expiration.  He's not watching the warranty and planning replacement.  It was probably very costly and unnecessary.  Where was the sysadmin that usually monitored the health of the RAID and planned the replacement?  Typical home users should not have RAID.

If the customer wants RAID, then give them RAID, but they need to be taught that RAID IS NOT BACKUP.  You still need to replace them before they fail.  If you're just getting RAID for the sake of having "RAID", then you or your customer is just not understanding the purpose of RAID.  This sounds like a home MAC user.  He doesn't need RAID storage space, uptime, or speed.  He just needs to store his data and 2 TB is just not that much.  It also sounds like he didn't have a sysadmin to monitor the system and plan a replacement.  He basically bought a Ferrari and treated it like a Buick.

Those 4 disk RAID units are junk.  You need at least 8 disks for decent RAID6.   4 disk units should only be in RAID 10.  Never use RAID 5 anymore, unless you're still using disks smaller than 1TB.  Why would you do that anyway when single disks come in 4Tb - 10TB now?  Units with 5-7 disks only really benefit in storage size, unless you have a 2nd unit for backup data, so why bother.  RAID 6 slows down the system too much that it's not worth that extra money for only a minor increase in speed and uptime at those sizes.

I would suggest the following for Windows users.
SATA drive bays work nicely
Use Robocopy in a scheduled task or HardlinkBackup, if you want deduplciation.

I would suggest the following for Mac or Windows.!#!
Use rsync in cron, or if he must use a GUI, try chronosync

When 1 drive fails, just pull it out of rotation and replace it.  Turn off the scheduled task.  duplicate the working disk.  You can use 2 SSDs if you want speed,  You should still back up to Backblaze for off-site storage.  You can get a 3rd disk and pull that one offline.

If the user actually needs multiple TB that exceeds a single disk, then that's the only time they should have a home RAID.

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