NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
Reallocation warning message
Hello experts require some expert advice. two days ago after a disk test i got an email from my readynas 314 that disk 1 had to be reallocated and it later added this could mean a disk is failing...
aniraghome wrote:
today i downloaded raidar 6.5 and it gave a number 1688 reallocation errors on disk 1? is it time to replace a new disk then?
Definitely it is time to replace it.
Opinions on when to replace a disk vary. Personally I will replace a disk before the reallocated sectors count reaches 50 myself. But everyone would say that ~1700 reallocated sectors is a failed disk.
aniraghome wrote:
i got this readynas 6 years ago in 2014 and i had then bought 4 X 3 TB Seagate Barracuda SATA III 7200rpm.
Don't get a new Barracuda - several of those are now SMR drives, and aren't good options for RAID arrays.
If you want to stick with 7200 RPM, then I'd suggest a WD Red Pro or a Seagate Ironwolf Pro. Currently shipping models start at 4 TB, so you would need to go with a bigger size. Note you'll need to upgrade two drives to the larger size to get more space in the volume. The capacity rule is "sum the disks and subtract the smallest).
Other enterprise-class SATA drives would also work (WD Gold to give one example).
If you want to stick with 7200 RPM, then I'd suggest a WD Red Pro or a Seagate Ironwolf Pro. Currently shipping models start at 4 TB, so you would need to go with a bigger size.
——————
Thanks again for your reply.
One question i have on disk buy : i have three other barracudas that are 3TB @ 7200 RPM cache 64mb if i get a wd or iron wolf that is 4TB and higher cache will that still be okay. If i get the new disk at 5400 isthere any harm different disks spinning at different speeds?
Assuming other three disks are fine if i do end up getting two disks apart from disk 1 which had these reallocated sectors which other disk can i swap/replace the new second disk with?
——————
Thanks again for your reply.
One question i have on disk buy : i have three other barracudas that are 3TB @ 7200 RPM cache 64mb if i get a wd or iron wolf that is 4TB and higher cache will that still be okay. If i get the new disk at 5400 isthere any harm different disks spinning at different speeds?
Assuming other three disks are fine if i do end up getting two disks apart from disk 1 which had these reallocated sectors which other disk can i swap/replace the new second disk with?
aniraghome wrote:
One question i have on disk buy : i have three other barracudas that are 3TB @ 7200 RPM cache 64mb if i get a wd or iron wolf that is 4TB and higher cache will that still be okay.
Yes. The disk size matters a lot (and as I said SMR disks should be avoided). Cache size doesn't.
One warning here - Netgear does recommend backing up the array before you replace disks. When you replace a disk, the system has to read every sector on the remaining ones to rebuild the array. That does stress the disks (and can uncover issues you didn't know were there). So it is a good idea to update your backup (or make one) first - even if that means you have to purchase USB drive(s) to do that.
aniraghome wrote:
If i get the new disk at 5400 is there any harm different disks spinning at different speeds?
If you mix speeds, then the RAID will slow down (likely somewhere between a pure 7200 rpm array and a pure 5400 rpm array) - but it should still work. I'm not mixing speeds at the moment, but I have done that in the past for some years and had no issues at all. The NAS will give you a warning about mixed speeds if you add a slower disk, but it will let you do it.
I think Sandshark did run into an issue (spin up time at boot?) where he suspected mixed RPMs were at fault - I don't recall the details or the strength of the evidence. Hopefully he'll join in and clarify that.
FWIW, although your Barracudas seem to have worked out for you, there are quite a few posters who had issues with them (and BackBlaze found them to be unreliable in RAID arrays). Given their age and track record, you might consider schedule replacing them over time, and not wait for them to fail. If you want to go with the less expensive (and cooler) NAS-purposed drives, then you could get one or more WD Red Plus (not a WD Red - they are SMR) or Seagate Ironwolf drives. You'll get the warning, but it should work out ok during the transition period when you are mixing them.
- Stephenb
Many thanks again for your guidance.
In looking at costs and avoiding smr’s i ended up with two choices. One is wd red plus which i see amazon and most othere doesn’t have stock till jan 3rd.
Dont want to push my luck So planning to go with “Seagate IronWolf 4TB NAS Internal Hard Drive HDD – CMR 3.5 Inch SATA 6Gb/s 5900 RPM 64MB Cache for RAID Network Attached Storage ST4000VNZ008/VN008)“ i plan to buy two this month and two next month just to spread the cost. When i get these new disks can i pop out disk 1&2 and pop these two in and let them sync?
I have a 5tb ext hd which i make 2nd copy of nas data. So from a data perspective i have a backuped them. When you say “while swapping disks netgear suggests backing arrays” how do i back them ?
I cannot thank you enough for this help.
aniraghome wrote:
Dont want to push my luck So planning to go with “Seagate IronWolf 4TB NAS Internal Hard Drive HDD – CMR 3.5 Inch SATA 6Gb/s 5900 RPM 64MB Cache for RAID Network Attached Storage ST4000VNZ008/VN008)“ i plan to buy two this month and two next month just to spread the cost. When i get these new disks can i pop out disk 1&2 and pop these two in and let them sync?Personally I test the disks first in a Windows PC using vendor tools (Seatools for the Ironwolf). I run the long non-destructive read test, followed by the full erase / write zeros test. You can connect the disks either via SATA or with a USB adapter/dock.
While some might think this is overkill, I have had disks fail out-of-the-box - including one I purchased last month. And I have had a couple of disks in the past that failed one of two tests, but not the other.
After testing I hot-swap the disks (with the NAS running). You do this one disk at a time, and wait until the resync is fully completed before you do the next one. You will see your volume expand by 1 TB when the second disk is synced, and it will expand an additional 1 TB for the third and fourth disks - giving you a 12 TB volume. The NAS reports this in TiB (which is ~10.9). Performance will drop during the resync, and it will take quite a while for each drive.
aniraghome wrote:
I have a 5tb ext hd which i make 2nd copy of nas data. So from a data perspective i have a backuped them. When you say “while swapping disks netgear suggests backing arrays” how do i back them ?Just make sure your USB copy is up to date - in case something goes wrong.
StephenB wrote:I think Sandshark did run into an issue (spin up time at boot?) where he suspected mixed RPMs were at fault - I don't recall the details or the strength of the evidence. Hopefully he'll join in and clarify that.
The problem I had was with OS4.2.x and drive spin-down enabled. Every few months, it appeared that one of the slower RPM drives didn't spin up in time, and was deleted from the array. Sometimes it was then re-detected and a re-sync began and other times I had to force it. That adds a lot of activity to the drives, potentially affecting life and definitely affecting access speed during the re-sync, and also puts you in a non-redundant situation during the re-sync. Disabling drive spin-down fixed the issue. I left the unit powered on continuously, so do not know if I would have run into a similar issue at power-on.
I never re-enabled drive spin-down on that NAS until the drives were replaced, even after updating to OS6. So I do not know if it is more tolerant of that situation. I have some 5400 and 7200RPM drives I've upgraded along the way, and I have an OS6 Pro6 not in use, so maybe it's time to intentionlly create a mixed-drive unit and see how it does. But I've moved all that to storage, so it'll be a bit before I get it going.
in OS6 there is an option Disk-Spin down did unchecking this fix your issue of multiple RPM's? i have this currently checked do i uncheck this ?
i have only one SATA III to USB cable and will run a short generic and long generic before i load it to NAS. is that good enough ?
aniraghome wrote:
in OS6 there is an option Disk-Spin down did unchecking this fix your issue of multiple RPM's? i have this currently checked do i uncheck this ?
Sandshark wasn't running OS6, but he did say that he'd disabled disk spin down.
I don't think there's a lot of certainty here on whether you need to do this or not, as I ran a mixed RPM RAID array on my pro-6 for some years (also running OS 4.2 at the time) and never saw this problem. I don't see enough data points to generalize.
But if you are concerned, you could uncheck it until all your disks are updated a month or so down the road. You'd use more power, but that's the only downside.
aniraghome wrote:
i have only one SATA III to USB cable and will run a short generic and long generic before i load it to NAS. is that good enough ?
Well, as I said earlier, I have had drives that pass the long generic test but fail the erase/write test (and vice versa). So I run them both. What is "good enough" is up to you.
NETGEAR Academy
Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!
