Hi guys, extreme help required. Added a second 4TB WD RED into slot 2 of my RN104 NAS tonight and everything started off ok and then suddenly I have the following flashing at me every few seconds..
data: DEGRADED
Now I am totally new at this, so I am now worried - I have read a bit about this prior to writing this but it is still a bit confusing.
All my data is still on the 4TB in slot 1 Currently the drive in slot 2 is not showing at all. The system is showing that slot 1 has a drive and slot 2 has nothing even though there is a drive their.
Also noticed that prior to inserting the new drive into slot 2 the RAID was JBOD and now it is saying RAID 1
How do I fix this ? I just wanted to add the second 4TB WD drive so to add more data as the slot 1 drive is nearly full - currently 755.41GB Free out of 4TB
Much appreciate the help and suggestions. I hope the change in RAID has not effected the data in any way.
The data would still be there.
njpryan wrote:
So the disk you added was used to add redundancy, not to add an additional volume.
Was there a way to prevent this ?
You could have disabled X-RAID before adding the second disk. Too late for that now.
Could be a good opportunity to update to the latest firmware if you have not already, backup your data, do a factory default (wipes all data, settings, everything), disable X-RAID, destroy the volumes, create the volumes you want etc.
njpryan wrote:
Can I change the RAID back to JBOD ?
You would need to destroy the volume (deletes all data) and create new volumes.
Considering there are the bones of 3TB of data and don;t have the room to backup to. Going forward I just need to run the diagnostic software on the new drive and see what that comes up with. From there what would I need to do - re-format the new drive ? and then insert it back to the NAS and what - don;t really understand the ins and outs of it clearly yet.
Well if you can't backup your data it clearly is not that important. No important data should be stored on just the one device.
If the drive is O.K. you could delete the partitions off it and try adding it again (to the same slot as before). If it is bad you would need another disk.
Adding the second disk would add redundancy. Using X-RAID you could then add a third disk to expand the volume.
The data is important and I do have external drives but just need to carry out a major tidy up of all data on those HDD to have the space to move the data from the NAS slot 1
It's the thoughts of it that is scary !! 🙂
Could take a while to move the data from the 4TB to different external hdd's
But we learn from our mistakes or lack of knowledge I suppose 😉
Just as a matter of interest - how do you go about deleting the partitions off the new HD I might try that after running the diagnostic tools. I will put up the reports on the drive later
Just as a matter of interest - how do you go about deleting the partitions off the new HD
On a windows PC there are two ways to delete partitions.
One is to use the diagnostic utilities (e.g., seatools or lifeguard) to zero the drives. One of them (I forget which) has a quick erase (zeroing sectors at the beginning and the end) which is enough to delete the partitions.
The second way is to right-click on "computer" and select "manage". A management tool is launched. Scroll down to the disk manager section, and right click each "volume" of the disk. Then choose delete. This will work even if Windows doesn't recognize the disk format (which it doesn't).
Ran the sea tools and the WD Lifeguard and both did not find the HDD - so presume it is DOA
Contacting the supplier to come and collect meaning that it will be 2 or 3 weeks before I get the drive back or replacement.
Many thanks for the support and advice as always.
A question about the RAID
When I added the drive it automatically changed the RAID from JBOD to RAID 1
Surely Removing the additional drive and just having the single 4TB in slot 1 as always that it would revert back to JBOD or there is a way to change it back to JBOD or am I misunderstanding the situation altogether.
You were using xraid, so when you added a disk it converted to raid-1. When you remove a disk it becomes degraded raid-1, not jbod. Unfortunately if you want to go back to jbod you need to destroy the volume and create a new one. Then restore the data from backup.
Hi StephenB, many thanks for the replies as always.
I am just wondering that when the XRaid was changed - was this on all drives ? In other words the initial drive in slot 1 which is still performing well, will I have to modify anything on this drive or is it the newly added second drive that changes need to be made. Also second HDD gone back and it will take 7-10 working days before I get a replacement which seems a very long time - even offered them a quicker solution but no joy - so will have to wait. Or is it the raid is determined by the OS of the NAS on determining how to read the drives.
Apologies if questions seem stupid but trying to get an idea on how it works.
The readynas software keeps track of the RAID mode in its database, and mounts the data volumes at boot time using that information.
When you get the new drive, you should hot-insert it into the NAS (into the same slot as the one you removed). XRAID will detect the new disk, and will resync it to the drive in slot 1. There won't be any changes to the existing drive.
FWIW, if the replacement disk is from Western Digital it will be a recertified drive. If you are getting it from the retailer it will be a new one. Either way it is a good idea to run Lifeguard on it before you insert it into the NAS.
Hi guys, I know its been a while since I was on last about this issue but here is an update.
Received the replacement 4TB from the web retailer and inserted it into SLOT 2 where it was originally and left it for a while. The good news is that the DATA DEGRADED has now disappeared and everything is back to normal except that from what I have learned from you guys (huge thank you !!!) I now have my RN104 in RAID 1 meaning that the SLOT 2 drive is a replica of SLOT 1
So now the next step I presume is I would have to get another 4TB drive for SLOT 3 to use for more data as SLOT 2 is used by SLOT 1 for backup purposes or as was stated at the beginning change the RAID factor from 1 to JBOD so to use the Drive in SLOT 2 as an extension to storage.
If you add another 4 TB drive in slot three, you will end up with an 8 TB data volume. Underneath, xraid2 will convert the RAID-1 volume to a RAID-5 volume automatically.
You will still have protection from a single disk failure but slot 2 will no longer be a mirror of slot 1. RAID-5 is more complicated than RAID-1.
Again it's been another while and everything is still the same with regards to my RN104 - Slot 1 (4TB), Slot 2 (4TB) and currently RAID-1
I have noticed of late that the space available has suddenly increased from 2GB (approx) to 4GB (approx) for no apparent reason. Also on a more scary note I keep losing connection to the RN104 on the web (ip192.168.1.1) - keep getting the server is currently busy and I click on re-connect but same issue. Any ideas ? I can still connect to it to add files etc but using the readynas software to connect and get the logs etc - not happening. I did carry out a restart and this worked for about 5 mins and then the RN104 started updating files and the connection was interrupted again on the web access but continues to work by adding files through the normal network.
With regards to the earlier conversation about RAID-1 and RAID-5 when I add the third 4TB drive - what is going to happen - e.g. will I have 12TB of storage or 8TB of storage and 4TB(slot 2) remains backup of Slot 1 - sorry in advance for seeming confused and repeating some questions.
As far as the lost connections go, it is best to follow whatever advice mdgm gives you after he analyzes your logs.
njpryan wrote:
I have noticed of late that the space available has suddenly increased from 2GB (approx) to 4GB (approx) for no apparent reason.
Do you really mean GB? or TB?
Do you have snapshots enabled?
njpryan wrote:
With regards to the earlier conversation about RAID-1 and RAID-5 when I add the third 4TB drive - what is going to happen - e.g. will I have 12TB of storage or 8TB of storage and 4TB(slot 2) remains backup of Slot 1 - sorry in advance for seeming confused and repeating some questions.
With xraid2, 2x4TB uses standard RAID 1, and gives you a 4 TB volume. When you add a third 4 TB drive it is automatically converted to RAID-5, and you end up with an 8 TB volume with single redundancy. Slot 2 will no longer be a mirror for slot 1 (as I said above, raid-5 redundancy is more complicated than that). Instead 4 TB's worth of redundant parity blocks are distributed across all 3 drives. This allows any failed (replaced) drive to be reconstructed from the other two.
The basic idea is that if Sector X on drive 1 and drive 2 are allocated for data, then Sector X on drive 3 is allocated for parity (and is the xor of the sectors X on drives 1 and 2). xor is a mathematical operation ("exclusive or") that operates independently for each bit in the sector.
0 xor 0 = 0 0 xor 1 = 1 1 xor 0 = 1 1 xor 1 = 0
It turns out that if
a xor b = c then a xor c = b and c xor b = a
So you can reconstruct any one of the sector X's from the other two. The parity block pattern is rotated (so 1/3 of the parity blocks are on each drive).
This recovery operation scales to 4 or more drives. Because if a xor b xor c = d then a xor b xor d = c and a xor d xor c = b and d xor b xor c = a.
So again, any single block that is missing in the "stripe" and be reconstructed from the remaining blocks.
If two or more blocks are missing in the pattern, then RAID-5 can't fix it.
Also, note that when you replace a disk, RAID-5 knows for certain which blocks need to be reconstructed. But if one of the blocks is somehow silently damaged (but can be read) then a xor b no longer equals c. RAID-5 can't figure which one is corrupt w/o help. The bit-rot protection feature in OS6 can (sometimes) figure out which block is bad, and reconstruct it according to the above formulas.
This is also why disk cloning is a last resort when repairing raid - it conceals which blocks are damaged, so there is almost always some file system corruption that RAID cannot repair.
Been a while since I was able to reply - apologies for that - I think I am unable to grasp the while RAID thing still.
With regards to the first replay - yes it is GB and not TB the change size is. I do have snapshots enabled but not for all folders
Now to the more complicated (for me 🙂 ) my NAS setup Currently with 2 of the 4 bays filled with both 4TB HDD's and currently set at RAID -1 which as I understand it as Slot 2 being a complete backup of Slot 1 - so while having 8TB of storage I actually have 4TB of storage and 4TB as backup.
Now here is my next step. I now have just received my 3rd 4TB HDD for Slot 3 (not installed yet as waiting gone your superb advice to date !!) While I currently cannot connect to my NAS using the web due to it continuously being offline and presuming this is something to do with it being busy with all my data as only 9% of free space left I have a question (eventually !) can I turn off the RAID on the NAS now prior to inserting the 3rd HDD and what effect will it have on the SLOT 1 and 2. Also if I just insert Slot 3 now I know you told me that it would change the RAID from 1 to 5 - what exactly would I have storage wise to work with ? Slot 1 4TB Slot 2 ? Slot 3? considering that the toal would be 12TB.
I obviously won't turn off the RAID if this would cause issues with my data etc and I won't do anything until I hear back from you.
I don't think I'd insert a new drive if the web interface wasn't responding. That's a sign of trouble. Maybe mdgm can comment...
On your other questions:
-You can't turn off raid unless you delete your existing data volume and switch to flex raid. That will destroy your existing data. If you decide to do it, create one volume for each disk.
-If you hot-insert drive 3 with the default xraid2, when the rebuild completes you will have 8 TB (~7.2 TiB) of storage, and protection any any single disk failure. Adding a fourth drive would bring you up to 12 TB (10.9 TiB).
If you want to protect your data properly you need an independent backup on a different device (even with RAID-1, and certainly with RAID-5). Try not to think about RAID as being a "backup"- it really isn't. By analogy, RAID is like having a spare tire in your automobile. If one tire goes flat, you are still good to go. But it doesn't protect from multiple flats, and it doesn't protect from engine trouble, battery failure, ...
Worried about your comment on the sign of trouble.
My NAS is on 192.168.1.1 But when I type in the address is used to be fine but now it appears with the following:
/Users/niallryan/Desktop/Screen Shot 2015-06-30 at 21.25.06.png
This has been appear for a while now - I have clicked on the Re-Connect several times and the screen re-appears. the only way to resolve it is to power off the NAS and re-start it and then it works fine for a while before re-appearing. The length of time working before the message re-appears is not consistent.
When you say that you wouldn't insert the third drive - why ?
I know magma did ask me to send logs but guess what ?? How ?? 🙂
