slow rebuild speed

[kenny1921]

i have recently epxerienced a few issues with a cable from the raid controller.

 

one of my 5tb drives got knocked off the array, i tried swapping cable 3 and 4 (both connected to the same 8087 connector on the same HBA)

I purchased a new drive to replace the drive and used a different cable from my second HBA, had to rebuild the contents on disk 4 and had a normal speed of 100 - 150mbps. i ran the old 5tb drive through a preclear and it passed so i assume the raid controller or cable was to blame

yesterday evening drive 3 got knocked off the array (drive 1 - 4) used the same connector on the same raid controller

i turned off the server this morning and swapped the cables so that no drives are using that cable, turned the server back on and get loads of read errors and a wierd tick then motor noise repeating from disk 2 (an old 1tb).

i turned the server back off and checked my cables are connected firmly, now turned it back on.

  - Drive 2 still says reallocated sectors (but is still online)

 - Rebuild of disk 3 is running at 50mbps

 

Disk 3 is a 4tb SAS drive using an adapter to change SAS to SATA

 

is there anything that can be causing the slow rebuild speed besides the sector count of disk 2

 

please find my attached diag file

 

i intend to replace disk 3 once this rebuild has completed and am also going to purchase 2 new cables plus maybe a new controller when i get paid

lissy-diagnostics-20191107-2351.zip

Edited November 7, 2019 by kenny1921

[JorgeB]

Nothing jumps out from the syslog, you can try diskspeed docker to see if all disks are performing normally.

[kenny1921]

thank you for the reply, i will try out the docker you suggested.

[kenny1921]

Very interesting tool thank you for suggesting it.

 

i let the build complete, replaced disk 2 with an un-assigned disk and went to rebuild. Was getting 45 - 50mbps build speed again.

 

i powered down the server and physically removed the 1tb drive from the server. Powered on and started the rebuild on the new disk (drive 2) and am now getting the usual 100+mbps speeds.

 

will end up replacing all the smaller drives in the array when I next get paid