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Forum Discussion
haspden
Oct 31, 2018Aspirant
ReadyNAS 6 - Raid 5 Drive Replacement
I am running a ReadyNAS 104 currently with 4 x 1TB Hard Drives...
I have these setup with Raid 5. it gives me the best perfomance & storage Raid option, whilst still maintaining 1 drive redundancy...
I have 2 questions.
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,
Next question, Currently I have 4x1TB, gives me 2.7TB of usable space on raid 5... which i totally get
What if I want to increase the capacity? If I swap a 1TB drive for a 3TB by swapping it out, i think I am right in saying I would get no ncrease in capacity... Ideally once this has re-sync'ed i'd then replace the 2nd, 3rd and then the 4th one by one waiting for a resync between each drive replacement & I would tripple my storage space...
1x3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 2TB Unused Space
2*3TB + 2*1TB = 3TB Usable Space + 996GB Protection + 4TB Unused Space
3*3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 6TB Unused Space
4*3TB = 9TB Usable Space + 3TB Protection
Would X-Raid would be more suited to wanting to increase storage space with incremental increases as each drive is upgraded?
in X-Raid how does it handle drive failure? I believe that the X-Raid system would result in only 2TB of usable space with 4*1TB drives?
Thanks
Henry
I am running a ReadyNAS 104 currently with 4 x 1TB Hard Drives...
I have these setup with Raid 5. it gives me the best perfomance & storage Raid option, whilst still maintaining 1 drive redundancy...
I have 2 questions.
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,You are correct, the RAID array will still work on DEGRADED Status and since 1 drive had failed then no protection/redundancy is present. OS 6 Supports Hotswap so Yes, you can swap out the failed and replace it with a new one. NAS will then Resync and complete RAID 5 array again. Please see replacing a disk
I am running a ReadyNAS 104 currently with 4 x 1TB Hard Drives...
I have these setup with Raid 5. it gives me the best perfomance & storage Raid option, whilst still maintaining 1 drive redundancy...
I have 2 questions.
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,
Next question, Currently I have 4x1TB, gives me 2.7TB of usable space on raid 5... which i totally get
What if I want to increase the capacity? If I swap a 1TB drive for a 3TB by swapping it out, i think I am right in saying I would get no ncrease in capacity... Ideally once this has re-sync'ed i'd then replace the 2nd, 3rd and then the 4th one by one waiting for a resync between each drive replacement & I would tripple my storage space...
1x3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 2TB Unused Space
2*3TB + 2*1TB = 3TB Usable Space + 996GB Protection + 4TB Unused Space
3*3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 6TB Unused Space
4*3TB = 9TB Usable Space + 3TB Protection
Would X-Raid would be more suited to wanting to increase storage space with incremental increases as each drive is upgraded?
in X-Raid how does it handle drive failure? I believe that the X-Raid system would result in only 2TB of usable space with 4*1TB drives?
Thanks
HenryYou are right again, you need to replace all drives in order to expand the volume. Please see ReadyNAS Volume Expansion and How do I expand existing X-RAID and What is X-RAID
Hope this helps!
Regards
2 Replies
Replies have been turned off for this discussion
- Marc_VNETGEAR Employee Retired
I am running a ReadyNAS 104 currently with 4 x 1TB Hard Drives...
I have these setup with Raid 5. it gives me the best perfomance & storage Raid option, whilst still maintaining 1 drive redundancy...
I have 2 questions.
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,You are correct, the RAID array will still work on DEGRADED Status and since 1 drive had failed then no protection/redundancy is present. OS 6 Supports Hotswap so Yes, you can swap out the failed and replace it with a new one. NAS will then Resync and complete RAID 5 array again. Please see replacing a disk
I am running a ReadyNAS 104 currently with 4 x 1TB Hard Drives...
I have these setup with Raid 5. it gives me the best perfomance & storage Raid option, whilst still maintaining 1 drive redundancy...
I have 2 questions.
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,
Next question, Currently I have 4x1TB, gives me 2.7TB of usable space on raid 5... which i totally get
What if I want to increase the capacity? If I swap a 1TB drive for a 3TB by swapping it out, i think I am right in saying I would get no ncrease in capacity... Ideally once this has re-sync'ed i'd then replace the 2nd, 3rd and then the 4th one by one waiting for a resync between each drive replacement & I would tripple my storage space...
1x3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 2TB Unused Space
2*3TB + 2*1TB = 3TB Usable Space + 996GB Protection + 4TB Unused Space
3*3TB + 3*1TB = 3TB Usable Space + 996GB Protection + 6TB Unused Space
4*3TB = 9TB Usable Space + 3TB Protection
Would X-Raid would be more suited to wanting to increase storage space with incremental increases as each drive is upgraded?
in X-Raid how does it handle drive failure? I believe that the X-Raid system would result in only 2TB of usable space with 4*1TB drives?
Thanks
HenryYou are right again, you need to replace all drives in order to expand the volume. Please see ReadyNAS Volume Expansion and How do I expand existing X-RAID and What is X-RAID
Hope this helps!
Regards
- StephenBGuru - Experienced User
haspden wrote:
If 1 drive fails, will the system to continue to work (obviously without redundancy at this point... Can I swap it out & replace the drive with a new blank one? I assume that, I can "hotswap" the drive & the NAS will resync the data to the new drive and re-establish the Raid Redundancy,
The system will continue to work, and you can hot-swap the replacement drive.
Note that this doesn't mean your data is safe. If a second disk fails during the resync (which does happen), your data will be lost. Also there are lots of other failure modes (and of course theft, fire, etc) that can result in data loss. The only way to keep your data safe is to back it up. Ideally your backup plan would consider disaster recovery (including ransomware).
haspden wrote:Would X-Raid would be more suited to wanting to increase storage space with incremental increases as each drive is upgraded?
Yes. You can also expand with flexraid, but it is more complicated (as you need to create and manage RAID groups yourself).
With XRAID, the capacity rule is "sum the disks and subtract the largest". For instance, 2*3TB + 2*1TB would give you a volume size of 5 TB (about 4.55 TiB). 4x1TB would give you 3 TB of space - your comment on that is incorrect.
You are correct in thinking that you'd need two 3 TB drives to get any expansion. That is required to maintain redundancy. Likely you will need to reboot after you resynce the second 3 TB drive in order to trigger the first expansion. After that, no reboot is needed.
Converting to XRAID is easy. Go to the volume tab in the web UI. If there is a green stripe on the XRAID control (on the right) then XRAID is already enabled. If there is no green stripe, then just click on that control.
FWIW, it is often more cost-effective in the long run if you use larger drives. You might consider going with 4 TB drives instead of 3 TB.
haspden wrote:
in X-Raid how does it handle drive failure?
It handles drive failures identically to flexraid. As noted above, XRAID just hides the complexity of managing RAID groups yourself.
XRAID uses multiple RAID groups to achieve vertical expansion. To give an example, let's take your 2x3TB+2x1TB case.
If you start with 4x1TB you only have one RAID group in the volume, and that is RAID-5.
Once you've expanded to 2x3TB+2x1TB, the system still has that RAID group. It also creates a second RAID group to use the remaining space. That would be 2x2TB RAID-1. Both groups have single redundancy. The two groups are joined, so there is only volume (and one file system). Files will be spread across both groups - as far as the file system is concerned, there is one virtual disk.
If disk 2 were to fail, then when you replace it the contents are reconstructed from the remaining disks. This is done separately for each RAID group. The 4x1TB group is rebuilt using RAID parity blocks (normal RAID-5 stuff). The 2x2TB group is mirrored, so the data is just copied from disk 1 (normal RAID-1 stuff).
Also, if you upgrade disk 3 to 3 TB, the first RAID group is just reconstructed. The second RAID group is expanded to 3x2TB (converted from RAID-1 to RAID-5). You still see a single volume, with 7 TB ( about 6.37 TiB) of space.
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