Fireball3 Posted August 20, 2013 Share Posted August 20, 2013 Hi, I'm desperately trying to do a "Parity Swap". If you are adding a new disk or replacing a disabled disk, try Parity-Swap. I changed the new drive (the biggest) to parity and the old parity to the missing drive. In an other tread i read a "copy" button should appear - but not here. What am I missing??? Running rc16c Cheers Fireball3 Quote Link to comment
dgaschk Posted August 20, 2013 Share Posted August 20, 2013 Does the missing drive have a red ball? Attach a screen shot. I believe that once the disk assignments have been made, starting the array will begin the copy procedure. Where did you read about the "copy" button. Quote Link to comment
Fireball3 Posted August 20, 2013 Author Share Posted August 20, 2013 Here are the screenshots Trying to find that thread with the "copy button" but its not so easy... Edit: Here is the "copy button" thread http://lime-technology.com/forum/index.php?topic=25433.msg221507#msg221507 once the disk assignments have been made, starting the array will begin the copy procedure. After assigning the disks I cannot start the array. Quote Link to comment
Fireball3 Posted August 21, 2013 Author Share Posted August 21, 2013 I gave up last night. My intention was to use the "missing" drive as a cache drive and simultaneusly put the new 4TB parity drive in use. But obviously there seems to be an issue with the "parity-swap" function. Because I didn't want to waste the night waiting for answers, I started the alternative. Since I still had the "missing" drive, I triggered a parity rebuild. After that I will pull the "missing" drive and use it as cache drive. I will let unRAID rebuild the "missing" on the old parity drive. Q1: Do I have to preclear a drive that is used for replacing a failed one? Q2: Do I have to preclear a drive that I intend to use as cache? Nevertheless, it remains be checked if this "parity-swap" function is broken in rc16c! I won't be able to contribute with testing after having the 4TB parity installed. Quote Link to comment
itimpi Posted August 21, 2013 Share Posted August 21, 2013 Q1: Do I have to preclear a drive that is used for replacing a failed one? Q2: Do I have to preclear a drive that I intend to use as cache? No in both cases. If it is a new drive then pre-clear is still advisable as a confidence check on drive integrity. Quote Link to comment
garycase Posted August 21, 2013 Share Posted August 21, 2013 If you've done what I think you have, you just lost all the data on disk #2 If you're doing a new parity sync onto a new parity disk, it's only using the currently configured drives to compute that parity. As soon as you started that process, you lost all the parity information needed to do a rebuild of your failed disk (#2). The safest way to maintain an UnRAID server is to ALWAYS have a spare drive equal to the size of your current parity drive. Then, if a drive fails, you can simply rebuild it onto that drive. If you want to increase the size of your parity drive, do it while the array is in good shape (no failed drives). I'm not sure what you did wrong in trying the swap-disable process ... but clearly it would have been a good idea to wait for a bit of help if the data on disk #2 was something you don't currently have backed up (you should, of course, always have a current backup ... but clearly many people do not do so). Quote Link to comment
Fireball3 Posted August 21, 2013 Author Share Posted August 21, 2013 @itimpi OK. Will try it without preclearing. @garycase In fact, I was doing some testing until now and replacing the 500GB parity with 4TB was the first step to start with the "real" server. As I explained: Since I still had the "missing" drive, I triggered a parity rebuild. I pulled the "missing" drive in order to force the "parity-swap". As I wasn't able to do "parity-swap", I put the "missing" drive back and started the parity rebuild on the 4TB drive. Parity was good before pulling the 500GB parity. Everything OK. Shares were accessible during the parity rebuild. I thought it would be good to practice a bit prior to "going live" with the server. I don't think that I did a mistake but it's true, that there is no step by step instruction on how to do a "parity-swap". you should, of course, always have a current backup ... but clearly many people do not do so This is funny, I read this argument every time, and I wonder how that should work? At some point one might have tens of TB of data. Might be costly to back up that amount of data. I fully agree with you, it would be better to do so, but it's not reasonable for private use. Quote Link to comment
garycase Posted August 21, 2013 Share Posted August 21, 2013 I fully agree with you, it would be better to do so, but it's not reasonable for private use. If your data is important enough that you are willing to build a fault-tolerant server for it, I'd think it's generally important enough to be sure you back it up. It's not all that expensive to maintain backups ... you don't need another server; just a set of spare disks to write the backups to -- and these can be older smaller capacity disks that you've since replaced with larger ones. Even if you have to buy additional disks for backup, the cost is down to < $50/TB these days (or even lower). In any event, I'd certainly not want to be without backups !! I have ~ 40TB between my two UnRAID servers; and it's ALL backed up. Quote Link to comment
Thornwood Posted September 3, 2013 Share Posted September 3, 2013 Because if this I created a Unraid server just to be able to test the parity swap. I have no data on the drives and I made the parity drive a 1.5TB with a data a 350MB. After completing parity check shutdown unplugged data drive and placed new 2tb drive as parity and old parity in drive slot. No button appeared. Quote Link to comment
dgaschk Posted September 3, 2013 Share Posted September 3, 2013 The data drive must be disabled, showing a red ball. Did the drive show a red ball? Quote Link to comment
chuck23322 Posted September 3, 2013 Share Posted September 3, 2013 Hi, I'm desperately trying to do a "Parity Swap". If you are adding a new disk or replacing a disabled disk, try Parity-Swap. I changed the new drive (the biggest) to parity and the old parity to the missing drive. In an other tread i read a "copy" button should appear - but not here. What am I missing??? Running rc16c Cheers Fireball3 Simple quesiton -- are you saying you did both at the same time? You can only change/remove/swap ONE drive at a time with Unraid. Change parity -- let it rebuild on the new drive. THEN AND ONLY THEN, change another drive. You can't change two drives at once. {And "trading" drives counts as changing two at once.} Or said another way -- if you have a drive that failed -- you must first 'rebuild' that drive before making any other changes to the unraid box. To recover ONE drive requires ALL OTHER drives (including the parity) to be available. It sounds like you created a self-inflicted "double drive" failure... unless I misread you. ~Update: Ignore me. See later. Quote Link to comment
JonathanM Posted September 3, 2013 Share Posted September 3, 2013 Because if this I created a Unraid server just to be able to test the parity swap. I have no data on the drives and I made the parity drive a 1.5TB with a data a 350MB. After completing parity check shutdown unplugged data drive and placed new 2tb drive as parity and old parity in drive slot. No button appeared. You have to start the array with the data drive missing, so it is disabled, then shut down and put the larger replacement drive in the parity slot, and the old parity drive in the disabled drive's slot. You can't do a parity swap when the array was healthy on the last shutdown, as you describe doing. Quote Link to comment
dgaschk Posted September 3, 2013 Share Posted September 3, 2013 Hi, I'm desperately trying to do a "Parity Swap". If you are adding a new disk or replacing a disabled disk, try Parity-Swap. I changed the new drive (the biggest) to parity and the old parity to the missing drive. In an other tread i read a "copy" button should appear - but not here. What am I missing??? Running rc16c Cheers Fireball3 Simple quesiton -- are you saying you did both at the same time? You can only change/remove/swap ONE drive at a time with Unraid. Change parity -- let it rebuild on the new drive. THEN AND ONLY THEN, change another drive. You can't change two drives at once. {And "trading" drives counts as changing two at once.} Or said another way -- if you have a drive that failed -- you must first 'rebuild' that drive before making any other changes to the unraid box. To recover ONE drive requires ALL OTHER drives (including the parity) to be available. It sounds like you created a self-inflicted "double drive" failure... unless I misread you. No. There is a special procedure called parity-swap-disabled. But the data disk must be disabled, showing a red ball to initiate this procedure. It's easy to make a disk have a red ball if needed... Quote Link to comment
Fireball3 Posted September 4, 2013 Author Share Posted September 4, 2013 Because if this I created a Unraid server just to be able to test the parity swap. I have no data on the drives and I made the parity drive a 1.5TB with a data a 350MB. After completing parity check shutdown unplugged data drive and placed new 2tb drive as parity and old parity in drive slot. No button appeared. Thank you for confirming. No. There is a special procedure called parity-swap-disabled. But the data disk must be disabled, showing a red ball to initiate this procedure. It's easy to make a disk have a red ball if needed... Agree, this procedure exists and the screenshots I provided in my prior post show that but it doesn't work. In my screenshots you can also see that the data drive is redballed. And after doing the parity drive swap nothing happens! Now that Thornwood has the same issue I think it's a bug somewhere. Quote Link to comment
Thornwood Posted September 4, 2013 Share Posted September 4, 2013 I created the issue by removing the data drive and yes that does make it red. I have contacted Tom regarding this. I have this test server for 2 more weeks prior to selling it but then I will make a new one. So for right now here is how it should work. Do parity check. All green power off. Remove test drive power on. Now should get red ball on removed drive. Stop array replace parity drive with bigger drive, replace red ball drive with parity drive. New button should appear to do parity swap. I think it should say copy or something. At this time button does not appear. Did I mis something? Quote Link to comment
garycase Posted September 4, 2013 Share Posted September 4, 2013 I created the issue by removing the data drive and yes that does make it red. I have contacted Tom regarding this. I have this test server for 2 more weeks prior to selling it but then I will make a new one. So for right now here is how it should work. Do parity check. All green power off. Remove test drive power on. Now should get red ball on removed drive. Stop array replace parity drive with bigger drive, replace red ball drive with parity drive. New button should appear to do parity swap. I think it should say copy or something. At this time button does not appear. Did I mis something? I don't have a system set up at the moment to check this, but I believe you have to unassign the missing drive; then start the array; then stop the array; and THEN do the re-assignments [new parity, old parity in place of the missing drive] ... and finally Start the array. Try that and see if it does the rebuild okay then. Quote Link to comment
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