Thank you so much! Perfectly succinct. I went with the offline swap since similar to someone else in the comments, I could not live with "Parity 2" being there permanently haha. I would have yolo swapped since I keep backups but I also then thought I'd rather not have to restore backups just in case.
I tried to do the copy method but it would not let me start the array if I tried to assign my old party drives to data drives in the same operation as adding the new party drives. I also only had start array not copy for some reason. I had two parity drives of 14TB and was upgrading them both to 18TB so I can start using larger data disks. I ended up doing it in the worst way possible (YOLO) thinking it was going to copy, and that is why it would not let me asign the old parity drives to data (so it could copy from t hem) when I started the array I can see its rebuilding, not copying. I am sure everything will be fine, but this video would have helped me like say putting it in maintence mode so I could fall back to my old parity drives if needed. At this point its running and probably best to let it finish, as I do not think starting a new operation that the old parity drives would be "known" anymore.
adding youtube chapters would be cool, maybe a newer video in the future to tackle other comments and cut down the long wait times for starting/stopping the array
I wish the parity - to - data swap would give you more than just the percentage like speed or something.. I've been looking at it stay at 1% for what seems like forever but its probably only like 2 mins. Thanks for the video!
The only thing is, my OCD is killing me now that the array has Parity2 but no Parity1. And you cannot simply change from parity 2 to parity 1 :P The calculations used for parity1 and parity2 are different so the disks cannot simply be moved. If you want to move parity2 to the parity1 position then you would need to rebuild parity. The alternative is just to remove parity1 and run without it leaving parity2 in place
right I was afraid of that, after I wrote that comment I had an unfortunate incident with the backplate of my bay. One of the connectors broke / went bad.. and coincidentally my parity disk was in THAT particular bay.. so now i'm doing an offline rebuild with the new disk straight away, as the parity was no longer valid, no idea what was happening. No choice I guess, server going to be offline for 4-12 days.
When doing Swapping Procedure A, the final outcome leads to the single Parity disk being called Parity 2. Does this matter? Can you make it just called Parity instead of Parity 2. Is there any reason to?
Hi, you can't just change parity 2 to parity 1. Each parity is calculated differently. To get very specific: parity 2 is slightly more difficult for the PC to calculate so it uses a bit more CPU. For normal usage it does not matter that it is called parity 2 though. If you want to change it you will have to recalculate the parity
@@techngo8473 if there is only parity 2 in the system does it still use more CPU? If there is only parity 2 is there any other functionality that is different?
A bit more CPU and otherwise nothing is different. It uses more CPU as the mathematical method to calculate the second parity is a bit more complicated than the simple XOR of parity 1
Hi, I would switch them one at a time. As you have 2 it's very easy: 1. Stop array 2. Switch first parity drive with one of the bigger new ones 3. Start array and sync (during sync you still have parity protection from your second parity drive) 4. Once done you stop array again 5. Swap second drive with new bigger parity drive 6. Statt array and sync again. 7. (Optional) add the 2 old drives as data drives Alternatively: 1. Stop array 2. Switch both parity drives at once 3. Start in maintenance mode and sync (this means you can't use unRAID till the sync is done 4. Once sync is is done stop array and start again. If anything goes wrong during 3 you can just undo it all and add the old parity drives back. This version is a bit faster overall but means during step 3 you can't access / change your unRAID data. Alternative 2 (unsafe) 1. Stop Array 2. Change both drives 3. Start array normally and sync This is as fast as the alternative before but skips the security step. During the sync of step 3 you have absolutely no protection. So if something goes wrong you can easily loose data. Overall i recommend the first version of steps
@@techngo8473 Thanks for the info I figure option 1 was the best method. I am replacing 2 16TB drives with 20TB's and adding the 16TB's to the data but can't afford downtime or risk data.
Is there a scenario to replace my parity drive by shutting down the server physically swapping old parity for new parity then powering back on and assigning the new drive as my parity ? i only ask this because i dont have any more sata connector space
Hi, you can definitely do that. My recommendation: 1. Stop current Array 2. Power down Server 3 disconnect old parity and connect new parity 4. Start server and assign new parity 5. Start array in maintenance mode 6. Wait for parity sync to complete By starting it in maintenance mode you can't use the array but it will make sure nothing is changed untill parity build is done. If a drive fails before your new parity is done you can just shut down server put in the old parity and start the array to access the lost drives files. You can of course also immediately fully start your array and continue using it. This will minimize downtime but you are at risk of loosing data until the new parity has been built
@@techngo8473 Am I correct to say that this is basically similar to method B "offline swap"? Also, am I correct to say that Unraid is using the data array to rebuild the new parity drive, and that the old parity drive is essentially out of the picture during the rebuild?
@@JeffYuYaoChiun You are correct in your assumption that this is basically method B. Also you are correct in that Unraid is using the data array to rebuild the new parity drive. I think this video explains it fairly good: th-cam.com/video/c-JNWoP2sSk/w-d-xo.html. As we mount the array in "Maintenance mode" no files on the data drives are being changed during the parity operation. This means that for that duration of the sync the old parity drive stays valid. If something bad happens while you are doing this procedure you can just put the old parity drive back in. Once the Sync of the new parity drive is complete and you start the array normally edits on the data disks can start happening and as such the parity will also be updated. At this point the old parity drive is no longer valid. This is also shown in the video linked above.
In the first method you build parity two and then disables parity one which is the old drive. The thing is that the parity 2 drive is different then parity one drive. So how come its working? Parity one is i think xor even parity whereas parity two is different method. So when you remain with parity 2 you actually remain with parity drive which is not the even parity mode.
Parity 2 is calculated in a different mathematical manner than parity 1. This way of calculation is more complex to explain and calculate than XOR but basically it can work on its own as a single parity or in combination with parity 1 as a dual parity. If this didn't work then we would not really have a true dual parity, as a failing parity 1 would lead to no protection being left.
@@techngo8473 you are absolutely right, that it has to worknon its own also. I went and did it via method 2, taking the array offline . Thank you very much. Was very helpful
![TechnGo []](http://yt3.ggpht.com/ytc/AIdro_lR43SR5SZacZ9I5TwSIyOsVa9RXORJaPZc-pbuGCfz9A=s48-c-k-c0x00ffffff-no-rj)
Parity-to-Data swap is a lifesaver. what a great feature. thank you unraid.
You have a rather relaxing voice. 10/10 would buy your audiobook.
Great tutorial, made the parity > data swap very straight forward. Many thanks.
Thank you very much for your service! Brief, clear and to the point.
I just did a yolo swap yesterday lol. Day late and a dollar short.
Thank you so much! Perfectly succinct. I went with the offline swap since similar to someone else in the comments, I could not live with "Parity 2" being there permanently haha.
I would have yolo swapped since I keep backups but I also then thought I'd rather not have to restore backups just in case.
I tried to do the copy method but it would not let me start the array if I tried to assign my old party drives to data drives in the same operation as adding the new party drives.
I also only had start array not copy for some reason.
I had two parity drives of 14TB and was upgrading them both to 18TB so I can start using larger data disks.
I ended up doing it in the worst way possible (YOLO) thinking it was going to copy, and that is why it would not let me asign the old parity drives to data (so it could copy from t hem) when I started the array I can see its rebuilding, not copying.
I am sure everything will be fine, but this video would have helped me like say putting it in maintence mode so I could fall back to my old parity drives if needed.
At this point its running and probably best to let it finish, as I do not think starting a new operation that the old parity drives would be "known" anymore.
adding youtube chapters would be cool, maybe a newer video in the future to tackle other comments and cut down the long wait times for starting/stopping the array
If I do the "Single, Dual, Single Swap" -- won't my new parity drive always show up as "Parity 2"? That would drive me nuts!
Yes it will. If that's not something you want then I recommend one of the other methods ^^
Thanks! It does not look so hard, now.
Very helpful! Thank you for making these vids.
I wish the parity - to - data swap would give you more than just the percentage like speed or something.. I've been looking at it stay at 1% for what seems like forever but its probably only like 2 mins. Thanks for the video!
Would it be beneficial to use a large SSD as a paritydrive for performance reasons?
Thank you
The only thing is, my OCD is killing me now that the array has Parity2 but no Parity1.
And you cannot simply change from parity 2 to parity 1 :P
The calculations used for parity1 and parity2 are different so the disks cannot simply be moved. If you want to move parity2 to the parity1 position then you would need to rebuild parity. The alternative is just to remove parity1 and run without it leaving parity2 in place
Thanks Sir keep on unraid Videos
In scenario #A how do I get Parity Drive 2, into the Parity Drive 1?
If you switch parity 2 into parity 1 you will have let parity calculate new. So you loose parity protection for that time.
right I was afraid of that, after I wrote that comment I had an unfortunate incident with the backplate of my bay. One of the connectors broke / went bad.. and coincidentally my parity disk was in THAT particular bay.. so now i'm doing an offline rebuild with the new disk straight away, as the parity was no longer valid, no idea what was happening. No choice I guess, server going to be offline for 4-12 days.
When doing Swapping Procedure A, the final outcome leads to the single Parity disk being called Parity 2.
Does this matter? Can you make it just called Parity instead of Parity 2. Is there any reason to?
Hi, you can't just change parity 2 to parity 1. Each parity is calculated differently. To get very specific: parity 2 is slightly more difficult for the PC to calculate so it uses a bit more CPU.
For normal usage it does not matter that it is called parity 2 though. If you want to change it you will have to recalculate the parity
@@techngo8473 if there is only parity 2 in the system does it still use more CPU? If there is only parity 2 is there any other functionality that is different?
A bit more CPU and otherwise nothing is different. It uses more CPU as the mathematical method to calculate the second parity is a bit more complicated than the simple XOR of parity 1
Nice video Friend! Thanks for sharing it with us!👍💖😎JP
Thanks for the tutorial. But what is the best way when I have 2 parity drives and want to replace them with 2 new bigger drivers?
Hi, I would switch them one at a time. As you have 2 it's very easy:
1. Stop array
2. Switch first parity drive with one of the bigger new ones
3. Start array and sync (during sync you still have parity protection from your second parity drive)
4. Once done you stop array again
5. Swap second drive with new bigger parity drive
6. Statt array and sync again.
7. (Optional) add the 2 old drives as data drives
Alternatively:
1. Stop array
2. Switch both parity drives at once
3. Start in maintenance mode and sync (this means you can't use unRAID till the sync is done
4. Once sync is is done stop array and start again.
If anything goes wrong during 3 you can just undo it all and add the old parity drives back. This version is a bit faster overall but means during step 3 you can't access / change your unRAID data.
Alternative 2 (unsafe)
1. Stop Array
2. Change both drives
3. Start array normally and sync
This is as fast as the alternative before but skips the security step. During the sync of step 3 you have absolutely no protection. So if something goes wrong you can easily loose data.
Overall i recommend the first version of steps
@@techngo8473 Thanks for the info I figure option 1 was the best method. I am replacing 2 16TB drives with 20TB's and adding the 16TB's to the data but can't afford downtime or risk data.
that´s sooo cool i can finally collect all my disks an put them toghether
Is there a scenario to replace my parity drive by shutting down the server physically swapping old parity for new parity then powering back on and assigning the new drive as my parity ? i only ask this because i dont have any more sata connector space
Hi, you can definitely do that.
My recommendation:
1. Stop current Array
2. Power down Server
3 disconnect old parity and connect new parity
4. Start server and assign new parity
5. Start array in maintenance mode
6. Wait for parity sync to complete
By starting it in maintenance mode you can't use the array but it will make sure nothing is changed untill parity build is done. If a drive fails before your new parity is done you can just shut down server put in the old parity and start the array to access the lost drives files.
You can of course also immediately fully start your array and continue using it. This will minimize downtime but you are at risk of loosing data until the new parity has been built
@@techngo8473 Am I correct to say that this is basically similar to method B "offline swap"? Also, am I correct to say that Unraid is using the data array to rebuild the new parity drive, and that the old parity drive is essentially out of the picture during the rebuild?
@@JeffYuYaoChiun You are correct in your assumption that this is basically method B.
Also you are correct in that Unraid is using the data array to rebuild the new parity drive.
I think this video explains it fairly good: th-cam.com/video/c-JNWoP2sSk/w-d-xo.html.
As we mount the array in "Maintenance mode" no files on the data drives are being changed during the parity operation. This means that for that duration of the sync the old parity drive stays valid. If something bad happens while you are doing this procedure you can just put the old parity drive back in. Once the Sync of the new parity drive is complete and you start the array normally edits on the data disks can start happening and as such the parity will also be updated. At this point the old parity drive is no longer valid. This is also shown in the video linked above.
@@techngo8473 Awesome stuff. Great videos. Thank you.
In the first method you build parity two and then disables parity one which is the old drive.
The thing is that the parity 2 drive is different then parity one drive. So how come its working? Parity one is i think xor even parity whereas parity two is different method. So when you remain with parity 2 you actually remain with parity drive which is not the even parity mode.
Parity 2 is calculated in a different mathematical manner than parity 1. This way of calculation is more complex to explain and calculate than XOR but basically it can work on its own as a single parity or in combination with parity 1 as a dual parity.
If this didn't work then we would not really have a true dual parity, as a failing parity 1 would lead to no protection being left.
@@techngo8473 you are absolutely right, that it has to worknon its own also.
I went and did it via method 2, taking the array offline .
Thank you very much. Was very helpful
Is there any downside to the second calculation technique? Does parity 2 fill up at a greater rate than 1 bit to 1 bit or is it slower?