My unRaid box has space for 12 drives, which are all filled (11+1 parity), and I'm running some version 3.x of unRaid. All the drives are IDE and almost all are 400GB. I'm beginning to run out of space. So I thought about upgrading the parity drive and one other drive to 500GB, but that looks like a relatively minor change with 1TB drives out there now. It looks like SATA is the way to go in the future, so I'd like to convert the unRaid to SATA drives gradually.

 

I'm wondering about how best to go about it. I'd prefer not to change the motherboard, which is the original Intel starter pack that provides four IDE channels. I'm using two Promise IDE controllers for the other 8 drives. I think there should be at least one more spare PCI slot, so I'm thinking of getting a SATA controller card and getting two 750GB SATA drives, using one for parity and one for data to replace an existing one, upgrading the parity drive first, of course.

 

Is there a better way? And should I do this before or after changing to unRaid 4.x?

It's just me, but I'd be tempted to upgrade to unRAID 4.1 first, make sure everything is stable and THEN try to migrate from IDE to SATA.  4.1 is based on the linux 2.6 kernel (greater hardware compatibility & reliability) and support for up to 14 drives (with Pro key).

 

I don't know which MB you have, but the upgrade should allow you to either:

 

1.  Add two large SATA drives (assuming your MB has the native connectors) and start moving your parity/data over, or

2.  Remove a PCI controller (along with its four drives), add a SATA controller (and up to four SATA drives) and then use any MB connectors to connect your old IDE drives (one or two at a time) and transfer the data.

Actually, 4.1 now supports up to 16 drives as described here in the release notes for 4.1 http://lime-technology.com/forum/index.php?topic=831.0

 

I too would upgrade to 4.1 first, then add drives.  I think the original Intel motherboard even has two SATA ports, so you might be able to just plug in your new 750G SATA  drive, assign it as parity, rebuild parity, then re-assign your old  parity drive as a data drive.

 

Joe L.

 

I've done this exact thing. I have the original mobo, with 7 IDE drives. I then added 2 500 GB SATA drives to the motherboard SATA ports, and made one of them the new parity drive.

 

Now I'm at the point where I want to take out one of the the IDE cards (its unused) and put in an SATA card, with at least 6 ports. Time to scour the board for suggestions!

Actually, 4.1 now supports up to 16 drives as described here in the release notes for 4.1

 

You're quite right Joe (as usual). 

 

My only defense is that the 14 drive "max" drive count was introduced with v4.0 (not 4.1 as you correctly pointed out) and is still listed on the unRAID website documentation (vice user forums).

How would I upgrade the parity drive (make it larger) and change it from IDE to SATA if I have no more space for hard disks in my case? I can of course remove an IDE drive and install the SATA drive, but the documentation seems to cover only the situation where an existing drive is replaced by a larger disk presumably on the same IDE/SATA channel. But if my larger disk is SATA instead of the current IDE, willl unRaid recognise that the disk in the SATA channel is meant to replace the now missing disk on the IDE channel AND that since it's bigger than the other disks, the new disk should be the new parity drive?

willl unRaid recognise that the disk in the SATA channel is meant to replace the now missing disk on the IDE channel AND that since it's bigger than the other disks, the new disk should be the new parity drive?

 

What do you mean?  You have to manually specify what disk you want to use for what purpose in the devices tab (i.e. parity, disk1, disk2, etc.).  AFAIK unRAID doesn't automatically do anything to any disks you plug into the system, which I like.

 

Personally I would just remove the old IDE parity drive, and replace it with the new 750GB SATA.  Then I would go into the devices tab and assign the new 750GB to parity, and recalculate parity from the main tab.  The downside to this is that you are unprotected until parity calculations are completed, but as long as you don't touch any of the disks on the array (writing/copying/etc.) I would think that you could put the old IDE parity disk back in if one of the HDD's spontaneously failed during the parity calc.

 

Someone will have to confirm the last part (putting the old parity back in and using it), but I don't see why it wouldn't work.

 

-kenshin

 

 

Ah, I assume this is a new feature in 4.x, as I don't recall seeing this capability (of assigning drives) in 3.x. The Documentation page of the website is a bit outdated. It says nothing about assigning drives; it only mentions replacing, which I took to mean changing only the drive, not the channel or type.

 

Your approach makes sense; I'll try that once I've upgraded to 4.1.

Ah, I assume this is a new feature in 4.x, as I don't recall seeing this capability (of assigning drives) in 3.x. The Documentation page of the website is a bit outdated. It says nothing about assigning drives; it only mentions replacing, which I took to mean changing only the drive, not the channel or type.

 

Your approach makes sense; I'll try that once I've upgraded to 4.1.

You are correct, it did not exist in earlier versions.

 

There are lots of things you can do now that a drive assignment page exists that you could not on earlier versions of unRaid.

 

The drive assignment page allows you to assign, or un-assign any drive to any slot when the array is stopped.

So... you could un-assign parity when you knew you would be loading lots of files on a new data drive to speed things up, then, once all the files are in place on the unRaid server, re-assign parity and calculate it on the entire array at once.  (Note: this leaves the array unprotected while the parity drive is un-assigned, and while re-calculating parity, but for some it will be worth it for the speedier transfer of data to the unRaid server)

 

You could perform a "parity swap" by assigning a new SATA drive to parity and assign the old parity drive as a data drive.

 

You can simulate a single failed drive by un-assigning it and re-starting the array.  You will still be able to get to its contents, and even be able to write to it as its contents are derived from the remaining drives. (Note: while in this mode, you would not be able to recover from the failure of a second drive)  In this mode on my array I was still able to stream 4 DVD ISO images to 4 different clients on my LAN from the missing (unassigned) disk.

 

You can simulate the replacement of a failed drive by re-assigning a drive you unassigned.  the unRaid server will then re-build the newly assigned drive's contents.

 

You can simulate the swapping of physical data drives by assigning them different logical slots in the array.  As long as you leave the parity drive in its same slot, and all other drives are allocated to some slot, you will be able to start the array.

 

You can simulate a hardware change that results in the physical disks ending up on different Linux devices.  (i.e., you swap out the motherboard, or a disk controller, and now what used to be /dev/hdb is showing up as /dev/hdk.)  Simply assign the same physical disk, regardless of what it is called, to the same logical slot in the array and you are up and running.

 

Joe L.

There are lots of things you can do now that a drive assignment page exists that you could not on earlier versions of unRaid.

 

The drive assignment page allows you to assign, or un-assign any drive to any slot when the array is stopped.

So... you could un-assign parity when you knew you would be loading lots of files on a new data drive to speed things up, then, once all the files are in place on the unRaid server, re-assign parity and calculate it on the entire array at once.  (Note: this leaves the array unprotected while the parity drive is un-assigned, and while re-calculating parity, but for some it will be worth it for the speedier transfer of data to the unRaid server)

 

You could perform a "parity swap" by assigning a new SATA drive to parity and assign the old parity drive as a data drive.

 

You can simulate a single failed drive by un-assigning it and re-starting the array.  You will still be able to get to its contents, and even be able to write to it as its contents are derived from the remaining drives. (Note: while in this mode, you would not be able to recover from the failure of a second drive)  In this mode on my array I was still able to stream 4 DVD ISO images to 4 different clients on my LAN from the missing (unassigned) disk.

 

You can simulate the replacement of a failed drive by re-assigning a drive you unassigned.  the unRaid server will then re-build the newly assigned drive's contents.

 

You can simulate the swapping of physical data drives by assigning them different logical slots in the array.  As long as you leave the parity drive in its same slot, and all other drives are allocated to some slot, you will be able to start the array.

 

You can simulate a hardware change that results in the physical disks ending up on different Linux devices.  (i.e., you swap out the motherboard, or a disk controller, and now what used to be /dev/hdb is showing up as /dev/hdk.)  Simply assign the same physical disk, regardless of what it is called, to the same logical slot in the array and you are up and running.

 

Very nice how to (I can't believe that unRAID can stream so quickly while generating data from a missing disk)