Okay, 2 (hopefully) quick questions. My System > Performance tab shows all 4 of my drives, temperatures, etc is the status section. The first 3 drive temps look good. However, drive 4 the temp is -1C / 30F. Do some drives not have this capability?
Also, on my Pro2 (running OS6 as well), I have other items on the Performance tab besides just Status. The include Volume, Network, Utilization and Temperature. On my RN104, those items don't show up. What gives?
What firmware version are you running? What device are you viewing the performance tab on, have you tried a different browser and clearing the cache on the browser? On the System, Volumes tab, are all disks green and is the volume status normal, and are the disks' smart stats normal? Have you done an OS reinstall?
All the RN104's disks are ST3000DM001's, but 3 are 9YN166 (firmware CC9D,CC9E & CC4H) and one is 1CH166 (firmware just updated last nite from CC24 to CC29 hoping to fix this). Also, this same disk had some errors a few weeks back, but it only happened for a few days, and I haven't had any now for 2+ weeks.
Detected increasing reallocated sector count: [15448] on disk 4 (Internal) [ST3000DM001-1CH166, Z1F193GZ] 74 times in the past 30 days. This condition often indicates an impending failure. Please be prepared to replace this disk to maintain data redundancy.
Increasing reallocated sector normally due to the drive becoming faulty. It will be safe though but to make sure is to replace it. Before doing that, check your dirve if it is really getting faulty. Turn off you NAS. Connect your 4th drive to a computer and run the disk tool utility and check whether the drive is really faulty. If it is, then I suggest you replace it. Turn on the unit with all drives on it, then once your NAS is booted and everything is accessible, remove the faulty one and hot plug a new drive then let it sync (make take a few hours to complete). Make sure the new drive is either same size or bigger than the original "faulty" drive. 🙂
You did not say what the volume page says about your volume. The disk most likely has failed completely as StephenB pointed out. I would say your situation is not safe, you need to replace the drive. Make sure you have a backup of data on the Nas. I think testing outside is reasonable where there is some doubt about the health of a disk. I think here it is fairly clear from your initial problem and the error count that the disk is dead or nearly dead.
Here's the S.M.A.R.T. info from (I'll try pasting it a couple of ways)
S.M.A.R.T INFORMATIONS Name Reallocated Sector Ct Temperature Start Stop Count Power On Hours Power Cycle Count Load Cycle Count Raw Read Error Rate Seek Error Rate Current Pending Sector Offline Uncorr. /dev/sda 20432 43.0 C 66 12316 65 92 146249384 4445709472 176 176 /dev/sdb 0 48.0 C 8 1287 8 8 153588496 13902723 0 0 /dev/sdc 0 51.0 C 237 13703 75 31234 101637304 134047933 0 0 /dev/sdd 0 46.0 C 414 19993 114 79451 199444304 8711338117 0 0
I started looking for some deals on new drives when I started seeing the error messages. Thinking of going with one of the WD Red Drives for a change. I'm going to need more space soon. I'm already down to less than 20% free. But, since all my other drives are 3TB, replacing one with a 4TB won't get me any benefit right now, correct? Don't I need to replace at least two drives with 4TB ones to gain additional space when using x-raid (raid5)?
Yes you would need at least two 4TB disks to see an increase in space. Replace one disk wait for it to finish resyncing etc. and for the volume to return to a redundant state then move on to the next disk.
Okay, I ended up ordering (2) x ST4000DM000 4TB drives for $315 delivered. I plan to obviously replace the one bad one (/dev/sda in slot #4). Is there another one that should be the next to be replaced? Or do I need to do one in the slot next to the other 4TB drive (ie /dev/sdb in slot#3)? The reason I ask, is the drive in slot #3 was just replaced about a month ago. The "Reallocated Sector Count" is zero for the other three. So all else being equal, I'd think I should replace either of the disks in Slot # 1 or #2 (/dev/sdc or /dev/sdd) with the other 4 TB drive. Will that work and give me ~1TB of extra storage? What's the formula for figuring it out?
As an aside, I believe the drives in Slots #3 & #4 were the ones I recycled from 2 Seagate GoFlex Home 3TB "NAS" units that I wasn't real happy with.
The formula for single redundancy is to sum the total of the all the disks, and then subtract the largest. This is in TB (multiples of 1000), not TiB (multiples of 1024). The NAS (like windows) reports TiB.
First hot-insert the 4 TB into slot 4, (e.g, remove the bad disk, and insert the new replacement with the NAS running). Then wait for the drive to be synced (added into the array). Then after that is complete, hot-insert the second 4TB drive into any of the other slots. If all the disks are solid, perhaps pick the one with the most power-on hours (which you can see in the SMART stats).
What about the "raw read" and "seek" error rates? Either way slot #1 has the most hours and the highest numbers for the raw read & seek error rates. So I can replace the disks in slot#1 & #4 and have the expansion work fine? Good to hear. I'll replace #4 first, wait for it to resync (a day or so until it states it's done). And the replace the other disk in slot #1.
Also, since the S.M.A.R.T. table above shows a "normal" temperature, what's up with the temp shown an the performance tab?
seek error rate and raw error rate have vendor-specific formats, which makes it difficult to know what to make of them.
I don't know what's going on with the performance tab data, but since you are replacing the disk anyway I don't think its a concern. If you still see the -1 after the new disk is inserted and synced, then submit a support request on that at support.netgear.com.
