How to convert a SPARE disk as DATA disk??

[NAYABRASOOL]

Hi all,

We have two spare disks out of which one we need to make as data disk can anybody help me out with command to do this. Will the "aggr add" will do please confirm.

Thanks

Nayab

[ankitbindal]

Hi Nayab,

To add the spare disk to aggregate, the drive has to be assigned to the that controller first

after that you may execute below mentioned command

aggr add <<aggregate name>> -d <<disk name eg. 0b.23>>

but do remember to check RAID size whether it is ok or not.

Regards

Ankit Bindal

[kuber · Accepted solution]

Nayab: As Ankit said you need to use the "aggr add" command to add the disk to the aggregate.... make sure you are adding the right  disk type... also check the RAID size for that aggregate using "aggr status -v" command.

since this is already showing as a spare... you don't need to assign it to the controller... as its already assigned.

Thanks

P.S: If my suggestion help please mark it as the "correct answer"

[NAYABRASOOL]

Hi Kuber,

Yes the disk was already present in the Aggregate as Spare disk the only thing i have to do is to make the spare disk as data disk hope the below command will do

FAS02> aggr add aggr0  -d <disk id>

Please confirm on this.

Thanks

Nayab

[kuber]

Yes that's the correct command... but you need to be aware that adding a single disk might cause performance issues on that aggregate as the newly added disk become a hot disk - getting most of new writes... It is always suggested to add a min of 3 disks to spread across all the new write evenly.

Thanks

[mike_burris]

FWIW, The best practice we adopted was that if you couldn't add a RG and had to do onesy twosy adds, make sure to run reallocate on the volumes on that aggr after the add was done..

[scottgelb]

agreed... add a full raid group at a time if possible... monitor disk utilization (statit output)... it won't be even but even enough without degradation.  And for most running dedup reallocate isn't supported until 8.1, so a good reason to be on 8.1 if you need reallocate...although compression on a volume doesn't support reallocate on any release.  Most often a full raid group addition works just fine.  The 3 disk recommendation was in a lot of the documents for a while but we adopted the full RG as well.

[NAYABRASOOL]

Hi Kuber,

What if i dont have automatic reallocation still i will get all the latest writes to the new disk coz i want the whole space to perform an activity on my filer i don wanna lose any space for this what i have to do..... to my knowledge i will be getting 267GB from a disk of 300GB SAS disk so i want to have whole 267GB to be added in to my aggregate is this possible or is there anyway that i can halt the new writes coming to this new disk as they will continue to write to the existing disks normally.

Please advise accordingly

Thanks,

Nayab

[VKALVEMULA]

check whether the disk is 'zeroed' before you add to aggr