Best 4 Bay External HDD Enclosure?

[FireWire2]

DATOptic.com update the item to Penta interface: USB3.0/USB2.0/FireWIre400/800 and eSATA.

This will fit nicely with new MacBOOK USB3.0 - Can wait to test it

Here is the correct link
http://www.datoptic.com/esata-fw400...sata-tray-less-jbod-raid-penta-enclosure.html

 

[JulianBoolean]

Hi All,

I've only read about 1/2 of this old thread from 2012, and my noggin has already reached information overload. Can anybody make a compelling case for me not getting an OWC Qx2? I only have a vague understanding of what a PCIe slot is, and what eSATA means, but I assume it has something to do with faster read/write speeds. I'm thinking that for TM backup purposes, that stuff I don't understand is not a big deal?

The empty Qx2 enclosures are currently available on sale for $175.00. I can get 2TB WD Caviar Green Drives for $99.00 from B&H. So that's 4 x 100 + 175 = $575.00... for 8TB total. That seems attractive, but I've not investigated other options too deeply.
http://eshop.macsales.com/item/OWC/MEQX2KIT0GBO/
http://www.bhphotovideo.com/bnh/controller/home?O=&sku=907586&is=REG&A=details&Q=

I'm thinking about using this implemented as RAID 5 for dedicated Time Machine Backup for about 2GB of current imaging work. Speed isn't really a biggie for me as it's just going to be used as a TM for incremental backups of my CGI & Retouching.

I'm using Super Duper to clone my boot drive and apps in Bay1 to another drive in Bay 2 of my Mac Pro Six Core. I have my working data drives in Bays 3-4. I keep running out of TM back up space for bays 3-4 as I currently have two 1.5TB OWC FW drives spanned together for 3GB total. I'm thinking this would be a reasonable, fairly low cost solution. Thoughts?

Thanks in advance!

Julian

 

[hfg]

Hi All,

I've only read about 1/2 of this old thread from 2012, and my noggin has already reached information overload. Can anybody make a compelling case for me not getting an OWC Qx2? I only have a vague understanding of what a PCIe slot is, and what eSATA means, but I assume it has something to do with faster read/write speeds. I'm thinking that for TM backup purposes, that stuff I don't understand is not a big deal?

The empty Qx2 enclosures are currently available on sale for $175.00. I can get 2TB WD Caviar Green Drives for $99.00 from B&H. So that's 4 x 100 + 175 = $575.00... for 8TB total. That seems attractive, but I've not investigated other options too deeply.
http://eshop.macsales.com/item/OWC/MEQX2KIT0GBO/
http://www.bhphotovideo.com/bnh/controller/home?O=&sku=907586&is=REG&A=details&Q=

I'm thinking about using this implemented as RAID 5 for dedicated Time Machine Backup for about 2GB of current imaging work. Speed isn't really a biggie for me as it's just going to be used as a TM for incremental backups of my CGI & Retouching.

I'm using Super Duper to clone my boot drive and apps in Bay1 to another drive in Bay 2 of my Mac Pro Six Core. I have my working data drives in Bays 3-4. I keep running out of TM back up space for bays 3-4 as I currently have two 1.5TB OWC FW drives spanned together for 3GB total. I'm thinking this would be a reasonable, fairly low cost solution. Thoughts?

Thanks in advance!

Julian

I have been using the OWC Mercury Elite Pro Qx2 for quite some time and am happy with it on my Mac Pro using an eSATA interface.

I would not use WD Green Drives with this in RAID-5 however. I initially tried this and found that the Green drives were not good in a RAID environment as sometimes a drive would be a bit slow to come up to speed and would be voted out of the RAID array. If you look on the OWC site page you referenced above, there is a link to a list of recommended drives for this enclosure. There they specifically mention the WD Green drives as not to use:

**NOT RECOMMENDED**
Seagate Barracuda 7200.11 series - all models, particularly the 1.5TB 7200RPM model p/n ST31500341AS due to stability and performance concerns.
Western Digital Green drives - all models, due to potential critical operational issues attributed to the IntelliPower technology providing inconsistent variable transfer rates.

-howard

The WD Green drives I tried were: WD20EARS 2.0TB which are older models (SATA II) than the one you linked above. I don't know if that will make a difference in a RAID-5 array or not.

 

[JulianBoolean]

^^
Howard,

Big thanks for the info on the WD Green drives, that's much appreciated. If the Greens don't work then I'm leaning towards two options:

1. The standard issue 8TB Qx2 on sale for $719.00
http://eshop.macsales.com/item/Other World Computing/MEQX2T8.0S/

2. Just a single OWC 4TB FW drive, and then JBOD span that together with the 3TB FW external that I already have. Not an elegant solution, but will get me to 7TB total, and will only set me back $360.00
http://eshop.macsales.com/item/OWC/ME3QH7T4.0/

Thanks again for your assistance

Julian

 

[nanofrog]

Howard,

Thanks for the info on the WD Green drives, that's much appreciated. If the Greens don't work then I'm leaning towards two options:

1. The standard issue 8TB Qx2 for $719.00
http://eshop.macsales.com/item/Other World Computing/MEQX2T8.0S/

2. Just a single 4TB FW drive, and then JBOD span that together with the 3TB FW external that I already have. Not an elegant solution, but will get me to 7TB total, and will only set me back $360.00
http://eshop.macsales.com/item/OWC/ME3QH7T4.0/

Thanks again for your assistance

Julian

Keep in mind, that if the Qx2 loses power (whether via the wall, or the batteries in a UPS are depleted) and is still in the middle of a write operation for a RAID 5 configuration, the data will be corrupted.

Given this is a backup, you'd likely be better off with a concatenated (aka Span or BIG; disks are streamed from end-to-end, so no loss of capacity, and has the speed of a single drive). The interface on it isn't that fast either (i.e. might see ~ 150MB/s or so IIRC), so there's no real throughput loss vs. a level 5 constructed of 4 members (where you'd be able to exceed 300MB/s with the right hardware configuration).

So a concatenated set tends to make more sense as a backup (schedule in the middle of the night so it's operation doesn't interfere with daily work).

 

[JulianBoolean]

Keep in mind, that if the Qx2 loses power (whether via the wall, or the batteries in a UPS are depleted) and is still in the middle of a write operation for a RAID 5 configuration, the data will be corrupted.

1. Hello again Nanofrog, nice to see you are still here dispensing pearls of wisdom. You (and Honumaui) helped me out quite a bit a few years back, and I'm eternally grateful. Regarding power failure: Hmm.. now that's a possibility I had not pondered. We do get power outages fairly frequently here in the Chicago area during the summer months. But, "the data will be corrupted" means, all the data on all four disks is corrupted ? (which would require a complete back up from scratch) or does that mean just the data from that particular hourly Time Machine back up set?

Given this is a backup, you'd likely be better off with a concatenated (aka Span or BIG; disks are streamed from end-to-end, so no loss of capacity, and has the speed of a single drive). The interface on it isn't that fast either (i.e. might see ~ 150MB/s or so IIRC), so there's no real throughput loss vs. a level 5 constructed of 4 members (where you'd be able to exceed 300MB/s with the right hardware configuration).

2. That makes sense. My only worry with a span set of four disks is that, one of the drives fail, and then one of my working drives fails shortly thereafter, before I have it backed up again, and I lose my original data. With a drive failure in a RAID5, I would have the extra safety of a rebuild of the back up by plopping in a new drive. Of course, the rebuild can fail, but I'd need a failed rebuild on the back up, and another fail on the original data to lose everything. So I guess it's a matter of weighing the risks associated with a power failure versus the risks associated with a concatenated set? A concatenated/span is what I currently have for back ups (two 1.5 TB FW Drives) and the two drive failure possibility, is my main stress worry scenario.

So a concatenated set tends to make more sense as a backup (schedule in the middle of the night so it's operation doesn't interfere with daily work).

3. One of my gripes with the Time Machine software is that I dont need hourly back ups. Twice a day would be ideal, but TM just keeps grinding out those hourly back ups, filling up my disk space whether I need them or not. I might make 8-10 incremental saves on the same 4GB image I'm working on, just as an insurance policy against a photoshop crash. Those incremental saves add up pretty quick on the back up drives. So, because I'm tight on space there, often I turn off TM during the day, but will forget to turn it back on at night. Is there some other software that can let me control the timing a bit better?

Thanks!

Julian

 

[hfg]

I guess I always use a UPS on my computer, so having a power failure during a backup would be pretty remote, since the UPS would signal my computer to shut down before the battery ran down, and the backup would be terminated.

The Qx2 can also be used in a "span" mode of operation, which would provide the full capacity of all 4 matched-size drives, but no redundancy or speed advantage. You could use the WD "Green" drives in this mode as they aren't striped.

I recall some posts here regarding changing the Time Machine backup frequency from Terminal to avoid the hourly incremental updates. I don't find the hourly incremental backups obtrusive, but do exclude files like Virtual Machines (30GB or so) to avoid the constant backup they would generate while in use.

I just ran a BlackMagic speed test on the Qx2 with 4GB test file size (older 1TB drives installed):
(eSATA interface with CalDigit FASTA-6GU3 eSATA/USB3 PCIe card in Mac Pro 5,1)

-howard

 

[FireWire2]

Howard

Just curious! the posted speed is SPAN mode right?

FW2

 

[nanofrog]

1. Hello again Nanofrog, nice to see you are still here dispensing pearls of wisdom. You (and Honumaui) helped me out quite a bit a few years back, and I'm eternally grateful. Regarding power failure: Hmm.. now that's a possibility I had not pondered. We do get power outages fairly frequently here in the Chicago area during the summer months. But, "the data will be corrupted" means, all the data on all four disks is corrupted ? (which would require a complete back up from scratch) or does that mean just the data from that particular hourly Time Machine back up set?

Ideally speaking, whatever data being written at the time of the failure.

But here's the thing... if it's writing the partition table for example (part that tells where every single chunk of data is on every member in the set), the entire set can be lost, particularly on systems such as the Qx2 (very basic hardware RAID on a Chip <aka RoC>), as there's no firmware in the device to keep a backup copy of the partition tables (what full fledged RAID cards tend to do). Gets ugly, and fast if you've not covered for these sorts of conditions (and you can never eliminate potential issues 100%).

2. That makes sense. My only worry with a span set of four disks is that, one of the drives fail, and then one of my working drives fails shortly thereafter, before I have it backed up again, and I lose my original data. With a drive failure in a RAID5, I would have the extra safety of a rebuild of the back up by plopping in a new drive. Of course, the rebuild can fail, but I'd need a failed rebuild on the back up, and another fail on the original data to lose everything. So I guess it's a matter of weighing the risks associated with a power failure versus the risks associated with a concatenated set? A concatenated/span is what I currently have for back ups (two 1.5 TB FW Drives) and the two drive failure possibility, is my main stress worry scenario.

I understand. Keep in mind however, that the statistical likelihood of this happening is very low, and usually considered an acceptable risk (not necessarily the case in all usage patterns, but those that this wouldn't work for, are far more complex than what you're using the system for - think credit card/banking transactions).

Here's an interesting situation with a concatenated set; if a member fails, the other drives can be returned to single disk operation, and the data is still in tact.

So if you ever experienced that super rare event (primary storage pool fails and all data is lost + backup fails simultaneously <or during the rebuild of the primary>), you wouldn't have as much lost data had the backup been a parity level on a Qx2. It's actually a benefit to run it this way instead of parity for both the primary and backup, when at least one of those parity implementations is based purely on an RoC (no memory, no Partition Table backups stored in the RAID card's firmware, ... types of features that are found on proper RAID cards).

 

[hfg]

Howard

Just curious! the posted speed is SPAN mode right?

FW2

No ... that was in RAID-5 mode.

I was expecting somewhat faster speeds from RAID-5 here. I wonder if it is my older technology disks, or the eSATA interface card I am using.


-howard

 

[bsbeamer]

No ... that was in RAID-5 mode.

I was expecting somewhat faster speeds from RAID-5 here. I wonder if it is my older technology disks, or the eSATA interface card I am using.


-howard

Used one in the past and had issues with slow transfer speeds. Contacted OWC and was basically told that large video files won't transfer as quickly as small documents (gee, thanks). Eventually was told that "incompressible" data (like the files generated by the Blackmagic speed test) aren't stellar performers with the Qx2. Had something to do with the controller. I'm not 100% sure on the tech inside the unit, but maybe someone else could shed some light on that. It wasn't a big deal for me since it was being used as an "archive" drive and just let the transfers take their time.

 

[hfg]

Used one in the past and had issues with slow transfer speeds. Contacted OWC and was basically told that large video files won't transfer as quickly as small documents (gee, thanks). Eventually was told that "incompressible" data (like the files generated by the Blackmagic speed test) aren't stellar performers with the Qx2. Had something to do with the controller. I'm not 100% sure on the tech inside the unit, but maybe someone else could shed some light on that. It wasn't a big deal for me since it was being used as an "archive" drive and just let the transfers take their time.

I replaced the older 1TB drives in my Qx2 with new Seagate 3TB drives in RAID-5 and the BlackMagic speeds improved a bit, 200MBs/220MBs with 4GB test size. However, when I tried using it with Time Machine, the transfer speeds are incredibly slow for some reason. The TM status bar shows that a 2.5TB backup will take 9 days, and Activity Monitor indicates that disk writes are occurring at only 2-10 MB/s ... way less than the 200 MB/s that BlackMagic DiskTest were getting.

I removed the CalData USB3/eSATA card and attached the Qx2 to the second eSATA port on a Velocity Solo x2 card and received similar results.

I don't see any firmware updates to this drives system on the OWC web site, but I will contact them tomorrow to see if they have any ideas why this is happening. Otherwise, I guess I will have to go back to the 1TB drives which were originally in there.

Anyone else have similar experience, or suggestions on what to try??


-howard

 

[bsbeamer]

I replaced the older 1TB drives in my Qx2 with new Seagate 3TB drives in RAID-5 and the BlackMagic speeds improved a bit, 200MBs/220MBs with 4GB test size. However, when I tried using it with Time Machine, the transfer speeds are incredibly slow for some reason. The TM status bar shows that a 2.5TB backup will take 9 days, and Activity Monitor indicates that disk writes are occurring at only 2-10 MB/s ... way less than the 200 MB/s that BlackMagic DiskTest were getting.

I removed the CalData USB3/eSATA card and attached the Qx2 to the second eSATA port on a Velocity Solo x2 card and received similar results.

I don't see any firmware updates to this drives system on the OWC web site, but I will contact them tomorrow to see if they have any ideas why this is happening. Otherwise, I guess I will have to go back to the 1TB drives which were originally in there.

Anyone else have similar experience, or suggestions on what to try??


-howard

I find that the drive is generally SLOW to transfer and build in RAID-5. I think the way it builds the redundancy across the drive is where the lag happens as it's basically the same exact speeds for me regardless of how I connect to it. I've NEVER been able to match the quoted spec speeds that others have had.

I've had luck with semi-speedy MicroNet RAID-5's in the past over USB/FW400/FW800 (and SCSI a LONG time ago), but their capacity wasn't nearly as large as the OWC Qx2 drives last time I checked. They don't make the same style units that I've used in the past and looks like the RAIDBank5 is probably the closest replacement.

 

[hfg]

I find that the drive is generally SLOW to transfer and build in RAID-5. I think the way it builds the redundancy across the drive is where the lag happens as it's basically the same exact speeds for me regardless of how I connect to it. I've NEVER been able to match the quoted spec speeds that others have had.

I've had luck with semi-speedy MicroNet RAID-5's in the past over USB/FW400/FW800 (and SCSI a LONG time ago), but their capacity wasn't nearly as large as the OWC Qx2 drives last time I checked. They don't make the same style units that I've used in the past and looks like the RAIDBank5 is probably the closest replacement.

After a long on-line chat with OWC, they finally asked one of the chief engineers and I found out that there is a chipset difference in the 2010-2011 models which precludes using larger disk drives over 2TB. Only the newer versions of the Qx2 will accept drives in the 3-4TB range and operate properly. This does bring up the question of the purpose of the "A - B" slide switch on the back for >2TB drives???

My unit (2010) would not do RAID-0 (switch #4) with the 3TB drives installed either, in addition to having a lethargic transfer rate with RAID-5 file transfers. Replacing the 3TB drives with the original 1TB drives restored full operation in RAID-0 and faster operation in RAID-5 ... so there may be some element of truth regarding the chipset used at the time of manufacture.

So ... I am now considering a new enclosure to preserve my recent investment in 4 3TB drives, but I don't know that I will buy another Qx2 unit!


-howard

 

[bsbeamer]

From their PDF:
1.5.5 2TB Switch (A-B switch)
Use position A for Operating Systems that support volume sizes over 2TB (OS X, Windows XP 64-bit, 2003 Server, Vista). Use position B to restrict the maximum volume size to 2TB for systems that do not support larger than 2TB volumes.

I've never moved them from "A" before...

On an unrelated note, was greeted with "Disk Utility can't repair this disk..." when connecting to this drive last night. Fun times. No issues with CalDigit HDPro - wish they'd make an archive version.

 

[JulianBoolean]

Hi All,

Thanks to everybody for the feedback on the QX2, much appreciated. I was able to obtain a lightly used unit from Flea Bay on the cheap, and it's working great so far. I was able to span it together with the two 1.5TB FireWire drives I already have for a total of 7TB for my Time Machine back ups.

Google searches (and commentary here) have turned up many problems pairing older units with newer 3-4TB drives, RAID5, and saving out large video files, but that's not what I'm asking it to do. I'm taking nanofrog's advice and just using it as a concatenated/span/jbod sitcha-machion. Given the limited, simple task I've assigned it to, its working out pretty nicely.

-Julian