More than 4 disks per volume on a 918

[sunsetdk]

Im attempting to add a 5 and 6 disk to my 918+ on DSM DSM 6.2.3-25426 Update 2

 

Add disk is grayed out, does 918 not support more than 4 disks per volume. 

 

I have tried to make a new volume with the extra 2 disk, that no problem. But i was hoping to change from SHR to SHR-2 and add the 2 extra disks to my primary volume.

[flyride]

I suspect that OP has #5 and #6 disks that are slightly smaller than the first four, so it won't allow them to be added to the array.

[flyride]

43 minutes ago, sunsetdk said:

does 918 not support more than 4 disks per volume

 

It has no practical limitations (24 disks for "high performance" configuration, even more for flexible).  More likely that your drives are not compatible with what you wish to do.

 

To verify, run this command from ssh and post the result here:

 

$ sudo fdisk -l | grep "^Disk /dev"

 

Edited October 25, 2020 by flyride

[IG-88]

2 hours ago, sunsetdk said:

Add disk is grayed out, does 918 not support more than 4 disks per volume. 

 

imho the "add drive" will only be available if there is a drive that can be added

remove the 2nd volume and storage pool and check if the drives are shown in the HDD/SSD area

 

[sunsetdk]

5 hours ago, flyride said:

I suspect that OP has #5 and #6 disks that are slightly smaller than the first four, so it won't allow them to be added to the array.

Hi you are right. The disks are smaller than the others. I didn't actually think this would be a problem as im adding and not replacing discs.

 

I will find some larger disks and try again (either that or rebuild volume where those discs are included)

[sunsetdk]

I have found the problem (smaller disk that the ones installed) but i promised to just attach the output from fdisk.

[IG-88]

just to mention the option, if you backup/offload your data you could delete the shr pool and create a new one with all disks including the small disks

[flyride]

If you are creating a SHR, you must include the smallest disks at the beginning or they won't be supported.

 

If you are creating a RAID, it will only use the storage on each disk that corresponds to the smallest disk in the initial array.  Unfortunately one manufacturer's "x terabyte" drive may be slightly larger than another, so some have run into the problem of trying to add additional drives marketed as the same size, but are still too small to function in the existing array.

[sunsetdk]

Most of what you write I am aware of (but thanks for pointing it out ). I honestly thought you could add a smaller drive later on tho. But thinking about it, it makes perfect sense. I'll buy a couple of larger drives I guess thanks a lot for then help guys and gals