NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
RN104 Resync Speed on 3rd Drive Replacement Very Slow
I am updating my RN104 from 4 8Tb drives to 4 10Tb drives. After replacing the first drive, the resync took a couple of days to complete. After replacing the second drive, about the same length of ...
I rebooted the NAS and the resync speed increased to about 14 Mb/sec. I don't know what was causing the slow down before.
I do have backup jobs running Rsync. This particular NAS does not have any backups configured on it, but it is the NAS that recieves backups from another NAS.
Ken6432-1 wrote:
After two days it is only at 53.7% and the estimate says it has 1240 hours to go. Is this normal?
That is unusually slow. Is the NAS doing something else (backup jobs, scheduled maintenance activities, or under a heavier usage then other times)? Resync is a lower priority task than other things, so it will run slower when there is more going on.
I suggest downloading the log zip file, and looking for disk errors in system.log and kernel.log
If ssh is enabled, you can get a better sense of the progress with cat /proc/mdstat and query the smart stats interactively with smartctl.
The cat command gives:
Personalities : [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
md1 : active raid10 sdd2[3] sdc2[2] sdb2[1] sda2[0]
1044480 blocks super 1.2 512K chunks 2 near-copies [4/4] [UUUU]
md125 : active raid1 sdd5[0] sdc5[1]
1952278144 blocks super 1.2 [2/2] [UU]
md126 : active raid5 sdb4[6] sdd4[4] sda4[3] sdc4[5]
11720633664 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [UU_U]
resync=DELAYED
md127 : active raid5 sdb3[6] sda3[7] sdd3[4] sdc3[5]
11706500352 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [U_UU]
[================>....] recovery = 84.3% (3290015080/3902166784) finish=7 593.8min speed=1343K/sec
bitmap: 0/30 pages [0KB], 65536KB chunk
md0 : active raid1 sdb1[6] sda1[7] sdd1[4] sdc1[5]
4190208 blocks super 1.2 [4/4] [UUUU]
unused devices: <none>
The resync=DELAYED is interesting. What does this mean?
Thanks again for you help.
You have a multi-layer volume due to incremental drive size upgrades. Each layer is it's own RAID, and it can only sync one at a time. So the delayed one is waiting for the another to complete. The multiple layers may be contributing to the slower speed.
Ken6432-1 wrote:
md127 : active raid5 sdb3[6] sda3[7] sdd3[4] sdc3[5]
11706500352 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [U_UU]
[================>....] recovery = 84.3% (3290015080/3902166784) finish=7 593.8min speed=1343K/secThis is extremely slow (1 to 2 MB/s). Did you look at the smart stats with smartctl (smartctl -x /dev/sda (repeat for the other disks).
Ken6432-1 wrote:
May 13 00:36:55 Media-Backup kernel: mvneta d0070000.ethernet eth0: bad rx status 0f830000 (overrun error), size=512
This is likely a consequence of the slowdown - the system isn't keeping up.
Ken6432-1 wrote:
May 12 21:46:38 Media-Backup sshd[3419]: Invalid user Retford from 192.168.1.1This is a little scary. Do you have ports forwarded to the NAS in your router? OR perhaps put it in the router's DMZ? If you have, then you should disable the forwarding (or put the NAS out of the DMZ).
StephenB wrote:
Ken6432-1 wrote:md127 : active raid5 sdb3[6] sda3[7] sdd3[4] sdc3[5]
11706500352 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [U_UU]
[================>....] recovery = 84.3% (3290015080/3902166784) finish=7 593.8min speed=1343K/secThis is extremely slow (1 to 2 MB/s). Did you look at the smart stats with smartctl (smartctl -x /dev/sda (repeat for the other disks).
I'm not sure what I am looking for. Nothing jumps out to me on /dev/sda, but that appears to be the 8Tb drive in the rightmost drive location. What would the address of the drive that is the third from the left? That is the one that was just changed.
Ken6432-1 wrote:
May 12 21:46:38 Media-Backup sshd[3419]: Invalid user Retford from 192.168.1.1This is a little scary. Do you have ports forwarded to the NAS in your router? OR perhaps put it in the router's DMZ? If you have, then you should disable the forwarding (or put the NAS out of the DMZ).
I have not set anything on my router that would have to do with any of my NAS's. In fact, I don't remember setting anything except the basic out-of-the-box settings. I agree it is concerning. I updated my passwords to be safe.
Ken6432-1 wrote:
I'm not sure what I am looking for. Nothing jumps out to me on /dev/sda, but that appears to be the 8Tb drive in the rightmost drive location. What would the address of the drive that is the third from the left? That is the one that was just changed.
Drive letters are normally sda->first slot; sdd-> fourth slot. But when you are upgrading disks, the system can assign letters differently.
One concern here is whether one of the drives (not necessarily the newest one) is failing. The sync speed will vary, but normally it'd be at least 30 MB/second - not 1.3 MB/sec.
If you are struggling understanding the smart stats, then perhaps instead download the full log zip file, and look for disk errors in system.log and kernel.log. Searching for sda, sdb, sdc, sdd would help locate them.
Ken6432-1 wrote:
I updated my passwords to be safe.
If the NAS has already been hacked, that is likely not enough.
Have you ever set up a NAS backup job that uses rsync-over-ssh?
Also, I suggest that you double-check your router settings, just to make sure there aren't any forwarded ports.
StephenB wrote:
Ken6432-1 wrote:md127 : active raid5 sdb3[6] sda3[7] sdd3[4] sdc3[5]
11706500352 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [U_UU]
[================>....] recovery = 84.3% (3290015080/3902166784) finish=7 593.8min speed=1343K/secThis is extremely slow (1 to 2 MB/s). Did you look at the smart stats with smartctl (smartctl -x /dev/sda (repeat for the other disks).
Is there something in particular I should be looking for? All four channels look similar to me. Nothing stands out on sdb as compared to the others.
Ken6432-1 wrote:
May 12 21:46:38 Media-Backup sshd[3419]: Invalid user Retford from 192.168.1.1This is a little scary. Do you have ports forwarded to the NAS in your router? OR perhaps put it in the router's DMZ? If you have, then you should disable the forwarding (or put the NAS out of the DMZ).
I have not made any changes on the router specific to the NASs. In fact I think they are set pretty much out-of-the-box. I updated my passwords to be on the safe side. I did see a similar entry on one of the other NASs that I checked.
StephenB wrote:
Ken6432-1 wrote:md127 : active raid5 sdb3[6] sda3[7] sdd3[4] sdc3[5]
11706500352 blocks super 1.2 level 5, 64k chunk, algorithm 2 [4/3] [U_UU]
[================>....] recovery = 84.3% (3290015080/3902166784) finish=7 593.8min speed=1343K/secThis is extremely slow (1 to 2 MB/s). Did you look at the smart stats with smartctl (smartctl -x /dev/sda (repeat for the other disks).
Ken6432-1 wrote:
May 12 21:46:38 Media-Backup sshd[3419]: Invalid user Retford from 192.168.1.1This is a little scary. Do you have ports forwarded to the NAS in your router? OR perhaps put it in the router's DMZ? If you have, then you should disable the forwarding (or put the NAS out of the DMZ).
What should I look for in the smart stats? I don't see anything noticably different between the output for sdb (the drive most recently changed) as compared to the other three.
I have done nothing on the router with respect to the NASs. In fact, I think the settings are pretty much out of the box. I see and entry similar to the one above on one of my other NASs that I checked. Very concerning. I updated my passwords to be on the safe side.
NETGEAR Academy
Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!
