This topic has been marked solved and closed to new posts due to inactivity. We hope you'll join the conversation by posting to an open topic or starting a new one.
Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontview
Hello,
We've got a Pro 4 with 4 x 3TB (WD30EFRX) drives, RAIDiator 4.2.27 and XRAID2 as single disk redundancy (SDR). We've expanded the unit over time (can't quite remember by how much and by when) but when we have expanded we've never done so using a Factory Reset (FR). With the above configuration (and our muddy history of expanding) this created a total of 7398 GB of usable space.
Q1. Was 7398 GB the correct amount of usable space we should have been seeing? We were under the impression that it should have been in the region of 9TB of usable space (3TB + 3TB + 3TB less 3TB for redundancy) so maybe we lost something there or simply just misunderstood the way that X-Raid 2 works?
Having now swapped 2x 3TB drives for 2 x 5TB (W50EFRX) drives our unit now consists of 2 x 3TB and 2 x 5TB. Following a successful resync and stripe (successfully expanded to 8326 GB and 10182 GB respectively) along with numerous reboots, Frontview (FV) is now reporting the unit as having 9TB but, the LED screen on the front of the unit is saying it has 10TB of usable space. Each of the disks are correctly reporting their allocated sizes under FV (2 x 4653 GB and 2 x 2790 GB) and we have another incremental backup program that displays the size of the destination disk (also showing 10 TB) but there is still a mismatch in sizes between FV and the LED.
Q2, So how much total space should the unit be reporting with our current configuration of 2x 3TB and 2 x 5TB under SDR if the unit had been FR?
Q3. If the unit should be reporting more, is there anyway to fix this without a Factory Reset?
Re: Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontvi
The addition of larger drives give us just a little more space (and time) to play with but I believe the only real solution here is a FR which we'll be working towards over the coming months.
Thank you very much though for all your help and suggestions.
Re: Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontvi
Q1. About 8.1TB is what I would have expected. Disk manufacturers use the base 1000 whereas like most computers we use the base 1024. 9*1000^4/1024^4 = 8.2. There is the 4GB OS partition and also the swap partition and there are of course overheads.
One may be rounding down while the other up. The volume capacity is just under 10TiB.
Q2. What you are seeing. 11*(1000^4)/(1024^4) = 10
Q3. It should not be reporting more. However you are unlikely to find that further expansion works. There are two expansion limitations:
i.) You cannot expand by more than 8TB over the life of the volume. So if the volume capacity was 2.7TB when you last did a factory default (wipes all data, settings, everything) you cannot expand past 10.7TB
ii.) You cannot expand past 16TB. You can do a factory default (wipes all data, settings, everything) to get a higher volume capacity. In that case the capacity of the smallest disk will be used so you should use disks of the one capacity. Thsi would be an issue when using 4x6TB disks or greater capacity disks.
Please note that we do not have any 5TB disks on the compatibility list for the Pro 4.
We've got a Pro 4 with 4 x 3TB (WD30EFRX) drives, RAIDiator 4.2.27 and XRAID2 as single disk redundancy (SDR). We've expanded the unit over time (can't quite remember by how much and by when) but when we have expanded we've never done so using a Factory Reset (FR). With the above configuration (and our muddy history of expanding) this created a total of 7398 GB of usable space.
There are two expansion limits that apply to 4.2.x firmware. One is that the volume will not expand over the 16 TiB ceiling, no matter what. That doesn't apply to you yet.
The second is that a volume cannot grow more than 8 TiB over its lifetime (starting from initial install or last factory reset). That might apply to you now, but would not have applied to your 4x3TB configuration.
If the logs have never been deleted, you can probably trace the history in expansion.log (though there is a lot of clutter in there that you might find confusing).
@wideef wrote: Q1. Was 7398 GB the correct amount of usable space we should have been seeing? We were under the impression that it should have been in the region of 9TB of usable space (3TB + 3TB + 3TB less 3TB for redundancy) so maybe we lost something there or simply just misunderstood the way that X-Raid 2 works?
One thing to keep in mind - Frontview reports storage in GiB/TiB units, not GB/TB. To convert GB to GiB you use the following formula:
This method is usually a bit higher than actual, since if doesn't account for all overhead. However, it is pretty close.
You were about 1 TB short of what you should have seen, which is more than the usual error.
I think there are two main possibilities:
-One is that the system was configured for 1 TB snapshot space. Check Frontview (volume page), and see what it says This is a rather large snapshot amount, the default is 10 GB. But it is conceivable.
-Another possibility is that you might have started with 2 TB drives, and that a vertical expansion step might have failed for some reason when you inserted the last 3 TB drive. That would also create a 1 TB discrepancy.
@wideef wrote: Q2, So how much total space should the unit be reporting with our current configuration of 2x 3TB and 2 x 5TB under SDR if the unit had been FR?
Well you should have 11 TB, which is 10 TiB. So frontview is still about 1 TB lower than the front panel.
@wideef wrote: Q3. If the unit should be reporting more, is there anyway to fix this without a Factory Reset?
Generally the answer is no. There is a manual off-line expansion that can be tried with ssh, but it carries some risks. And in your case, the two failure scenarios I can think of (snapshot space too large or failed vertical expansion in the past) makes me think it wouldn't work anyway. You could try Netgear support (or perhaps a Netgear person here might be willing to review your logs).
If you were to do a factory reset, you would be able to expand up to 3x6TB+5TB. Anything more than that would take you over the 16 TiB ceiling.
FWIW, if you are facing a factory reset anyway, you could consider OS 6 - which doesn't have these expansion limits. It is unsupported, but you are likely out of warranty anyway.
Re: Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontvi
So firstly thank you to you both for taking the time to clarify things. In terms of questions raised;
1. Logs: These were reset earlier on in the year due to an issue with the unit but having had a search of our archives we do have a few saves that were made at different times over the years. There is as you pointed out an overwhelming amount of information to sift through but if there is a specific section of the expansion log that might help reveal the whereabouts of the 'missing 1TB" (M1T) then we'd be happy to dig these out for you*.
*Is there anything in the expansion logs that could compromise security through posting?
2. Warranty; This has expired
3. Snapshots; The unit in FV currently reports 'Additional 10 GB reserved for snapshots'.
StephenB wrote:
If the logs have never been deleted, you can probably trace the history in expansion.log (though there is a lot of clutter in there that you might find confusing).
You were about 1 TB short of what you should have seen, which is more than the usual error.
-Another possibility is that you might have started with 2 TB drives, and that a vertical expansion step might have failed for some reason when you inserted the last 3 TB drive. That would also create a 1 TB discrepancy.
If we rule out the Snapshot theory then the MIT appears to point to a corrupt expansion somwhere along the line. We did indeed move from 2TB through to 3TB at some stage but by the sound of things the only risk-free way of really addressing this would be to carry out a FR.
FWIW, if you are facing a factory reset anyway, you could consider OS 6 - which doesn't have these expansion limits. It is unsupported, but you are likely out of warranty anyway.
Are there any good reads regarding the pros and cons of OS 6 vs Raidiator? We've been pretty happy with Radiator and the way it's worked for us with the exception of the expansion issue
Re: Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontvi
I wouldn't recommend posting logs here, though sharing log snippets is often done. The way Netgear wants to receive logs is via email (the details are in mdgm's signature).
If we rule out the Snapshot theory then the MIT appears to point to a corrupt expansion somwhere along the line. We did indeed move from 2TB through to 3TB at some stage but by the sound of things the only risk-free way of really addressing this would be to carry out a FR.
Assuming an earlier expansion did fail - the issue here is that you've expanded again after that, using still larger disks. So the waters are a bit muddied.
Are there any good reads regarding the pros and cons of OS 6 vs Raidiator? We've been pretty happy with Radiator and the way it's worked for us with the exception of the expansion issue
There are some posts on the subject, unfortunately the subforum for OS6 on legacy devices on readynas.com wasn't carried over (though the posts are all here).
OS6 uses BTRFS as a file system, not ext. There is a performance hit for writes, but the snapshot feature is more powerful. It also includes built-in Antivirus (which can be turned off). The linux kernel is newer. ReadyCloud currently only works with OS6 (though Remote still works with OS 4).
One thing that is missing is the ability to send a WoL packet at the start of a backup job. Some add-ons for OS4 don't have OS6 app equivalents.
Personally I continue to run 4.2.x on my pro-6. But I am at the point where more expansion would take me over the 16 TiB ceiling. When/if I reach that point, I'll likely switch to OS 6.
Re: Expansion with X-Raid2, resulting sizes and different reported space on NVX Pro 4 unit / Frontvi
The addition of larger drives give us just a little more space (and time) to play with but I believe the only real solution here is a FR which we'll be working towards over the coming months.
Thank you very much though for all your help and suggestions.
