RAID JDOG
- Thread starter LunarMist
- Start date
ddrueding
Fixture
Assuming you mean JBOD 
Files can be recovered from individual drives, but there are no guarantees which files are on the good/bad drives, and any files that split a drive are certainly toast.
This uncertainty makes it really not dependable as a redundant array. Best to assume that the good drives are re-usable, but the data can't be relied upon.
Files can be recovered from individual drives, but there are no guarantees which files are on the good/bad drives, and any files that split a drive are certainly toast.
This uncertainty makes it really not dependable as a redundant array. Best to assume that the good drives are re-usable, but the data can't be relied upon.
ddrueding
Fixture
The kludgy thing to do it mount drives as directories off an existing drive structure. I am not a fan of this technique. The most straightforward thing to do is use RAID arrays. You can go for JBOD, just be sure you have a backup. And if you are going to be sure to have a backup anyway, just go with RAID-0. Sure the chances of failure are higher, but still within reason, and you have backups, no?
The backup is the same size as the data of course. For example for a 2TB drive there is another 2TB backing that up. The problem is that I have to replace both of those drives with 3TB drives (~$350) just to gain 1TB of usable capacity. Now if I want to add 2TB of capacity that would require swapping out 4 drives and cost $700. The efficiency is appalling if I want to continue with the same number of drives and drive letters. RAID 5 or 6 does practically nothing for me other that consolidate drive letters. It wastes the space of at least two drives (one in the data array and one in the similiar backup array) and requires good controllers, complicated external connections, and only works well with certain drives.
ddrueding
Fixture
I never mentioned RAID-5 or RAID-6. Those, as you say, waste space. I mentioned RAID-0, which is not far from JBOD in terms of reliability and much faster. You still get to use all your space and consolidate drive letters. The only drawbacks are that you need to use drives of the same size and avoid WD 5400RPM drives.
Thanks. So can I RAID 0 the Samsung or Hitachi advancing format drives in XP64 or will performance really suck from the alignment?
I suppose it would be possible to break the SFF connector outside of the computer into an external case but would it have to be running when the computer boots?
I suppose it would be possible to break the SFF connector outside of the computer into an external case but would it have to be running when the computer boots?
ddrueding
Fixture
I have 2 6-disk RAID-0 arrays with Hitachi 3TB drives, and I get 500MB/s+ read and write. Better than single drives, that's for sure.
ddrueding
Fixture
I'll mix brands. I have no problem with that, particularly with Windows-based "soft-raid".
ddrueding
Fixture
If the drives are OK, just plug them into another computer and import the array. Done it several times.
CougTek
Hairy Aussie
Two RAID 0 arrays backing each other is simillar to RAID 0+1. Reliability-wise, you would be far safer with RAID 1+0. It was wiser ten years ago and that hasn't changed nowadays. Not harder for the controller either. No additional wasted space compared to what you already do (50% waste).
CougTek
Hairy Aussie
Oh that's reassuring :roll: That you've had to do it several times, I mean.
ddrueding
Fixture
The drives were fine. One was a blown motherboard, the other was an OS change.
How is that the same? RAID is not a backup. When data is accidentally deleted or overwritten you are screwed. You can't power the other drives down 23.5 hours per day either.
ddrueding
Fixture
So long as the two RAID-0 arrays are on different computers with a time-delayed (or manual) backup, it is far more secure than 10 or 01.
ddrueding
Fixture
What complexity and mediocre performance? 500MB/s isn't bad. What do you use for backups now?
ddrueding
Fixture
GbE is fine if you can get it set right. If one of your computers has two GbE NICs on it, the easiest way is to bridge them in Windows and then connect one using a crossover directly to the other.
"Rest of Network" -> "Regular Cable" -> "Computer with 2 NICs bridged" -> "Crossover Cable" -> "Other Computer"
This gives both machines quick access to everything else, but super quick access to each other.
"Rest of Network" -> "Regular Cable" -> "Computer with 2 NICs bridged" -> "Crossover Cable" -> "Other Computer"
This gives both machines quick access to everything else, but super quick access to each other.
CougTek
Hairy Aussie
It is impossible to get 500MB/s on a single or even on two combined GbE connexions. A single GbE link won't go over ~100MB/s.
ddrueding
Fixture
500MB/s is the benchmark score test. The fastest I can do between the two RAID0 arrays over the network is 118MB/s.
Internally there are 6 main data drives (2TB), not to mention the SSDs. There are 3x 2TB internal backup drives and 3x 2TB external eSATA backup drives. The externals are connected individually to a SIL 3114-based card and housed in a small 4-bay Addonics enclosure that is controlled by an X10 remote. (One of the 4x 2B drives is for archives and not backed up live.) The 3x 2TB internal backup drives are connected to various ports that support the hot swapoing, i.e., either motherboard add-in controllers or the LSI 9211-8i controller. The power to the three internal backup drives is controlled with a switch on the case that was originally intended for the controlling a goofy light. (For the electrodudes: There is a relay with a simple timing circuit and some noise/spike mitigation.)
When I feel the urgent need to back up I turn on the internal drives with the left small finger and turn on the external drives with my right index finger on the X10 remote adhered to the leg of the desk. After the drives are recognized I run the six SmartSync profiles all at the same time. After sync is finished I flush the disks and turn off the backup drives after 30 sec. or so.
The traditional incremental/differential backups are done about once a week with 2.5" drives and stored in my work briefcase or the old outside car. I ship drives or take the files to another state when I visit every few months.
ddrueding
Fixture
Sounds pretty good. You could keep the two RAID-0 arrays on the same computer as well, but I have had a PSU go ballistic and take everything with it before. I like having the two copies of the data on two different machines. Better protection against viruses as well.
I don't think it would be a great idea to have a backup array on another computer, becauce I might get the two computers computers confused and change files on the backup system accidentally. That would be chaos.
Maybe I should make two RAID 0 arrays, one in the computer and one external.
Maybe I should make two RAID 0 arrays, one in the computer and one external.
ddrueding
Fixture
I avoid confusion by having one drive be letter "z" and the other be drive letter "y". The letter is the same no matter which computer you are on. Z is the master and Y is the backup, even if you are working on the computer with the Y drive on it, you still work on the Z drive. I was toying with the idea of removing any drive letters at all from the Y drive, but my backup software doesn't like that.
Arrrghh! This is not going well. So far I found that the one enclosure labeled as JDOG is just two separate drives in Windows whereas I thought it was one volume. Then one of the newer Samsung 2TB hard drives I was moving around in the system was destroyed. There was some smoke and the dreaded burning smell. I hosed the drive off in the shower and trash-canned it.
Then one of the newer Samsung 2TB hard drives I was moving around in the system was destroyed. There was some smoke and the dreaded burning smell. I hosed the drive off in the shower and trash-canned it.
ddrueding
Fixture
JBOD is "just a bunch of drives". If you manage the RAID arrays in Windows you will have an easier time of it. It does support JBOD (spanning) and RAID-0 (striping) in all versions that can handle dynamic disks.
Chewy509
Wotty wot wot.
IIRC, that's because Windows treats all USB drives as not having the option to have a MBR or GPT. eg they should only contain a single filesystem, like a floppy drive!Dynamic Disks is greyed out for USB 3.0.
If you use a 3rd party partitioning tool, just construct a GPT on the drive, but define no actual partitions. Get Windows to remount the drive, and hopefully the option should appear.
Chewy509
Wotty wot wot.
Ignore this, as it appears to only work on Firewire connected drives and not USB drives... (Something in the USB stack prevents Windows from seeing USB drives as "fixed" drives, so disable the dynamic disk option. But with a quick regedit, you can tell the Windows Firewire stack to see all firewire drives as "fixed" disks therefore enabling dynamic disks with firewire devices).
For those interested for firewire, goto:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\dmadmin\Parameters
Then setting the following key: "EnableDynamicConversionFor1394" to 1 allows firewire devices to be turned into dynamic disks.
Heh. No more Firewire for me after the disasters in 2003.
I replaced a pair of the 2TB old-school 7200 RPM Hibachis with one each of the 7200 RPM and 5400 RPM 3TB drives. 2.6 TB was copied in under six hours so at least something was accomplished. Now I have been working with the external backup eSATA drives on the old SIL 3114, which sounds like something Santilli would use. I tried the RAID 0 mode and also the Windows software RAID 0. It is straightforward to import the array from different controllers and into another computer, so I will go that route. It is faster with one drive on another eSATA controller. I'm not sure about striping a pair of the primary data drives yet.
I replaced a pair of the 2TB old-school 7200 RPM Hibachis with one each of the 7200 RPM and 5400 RPM 3TB drives. 2.6 TB was copied in under six hours so at least something was accomplished. Now I have been working with the external backup eSATA drives on the old SIL 3114, which sounds like something Santilli would use.
I tried the RAID 0 mode and also the Windows software RAID 0. It is straightforward to import the array from different controllers and into another computer, so I will go that route. It is faster with one drive on another eSATA controller. I'm not sure about striping a pair of the primary data drives yet.Is there anywhere else I can find an SATA passthrough like this? The only other stores I find have terrible RR ratings.
ddrueding
Fixture
I just run SATA->eSATA cables out a missing bracket.