We have bought a new FAS 2020 System, it came with 12 hard disk and RAID-DP configured. Now, I have allocated 10 Hard disk to aggreate using GUI. But I am unable to add other 2 drives to aggregates, a error messge comes saying, the RAID technology you are using needs two hard drives as spares. I don't want to use spare hard drives for the RAID-DP. Can anybody help in this matter please?
Leave one hot spare, otherwise you'll be bombarded with error messages (well, it also makes technical sense IMHO)
The other one could be added via CLI:
aggr add <your aggrname> 1
I think you are trying to have more than at present.
Out of 12 Internal Disk. 10 Disks are already utilized in RAID-DP.
We support RAID-4 and RAID-DP.
Now minimum disk for RAID-4 is 2 which you can achieve using the remaining 2 Disks. However, then both the Aggregates ( RAID-4 & RAID-DP) will be running without any global hot-spare.
If you want to have more usable space, you can add 1 disk ( out of the 2 remaining). NetApp best practice is to keep atleast 1 hot spare within 2 disk shelf ( if using RAID-DP). But be carefull, you are using internal disks
and hence you wont be able to mix them with the external shelf later on, unless they are 1TB SATA drives as internal disks.
You can convert your current RAID_DP configuration to RAID 4 however you will lose the benfit of the additional drive protection. The NetApp Filerview by default does not allow to add the last two disk into a raid group. You have to add the single disk through command line and force it. You can only add a single disk out of the two spares. You can not run a system without a spare disk, the system will not allow. NetApp filer will shutdown by default after running for 24 hours without a spare drive in an event a spare has been used up by a failed disk event. To add a disk comamnd is: aggr add <aggr name> -f -d <disk name>
I hope this helps
You tell the following:
You can not run a system without a spare disk, the system will not allow. NetApp filer will shutdown by default after running for 24 hours without a spare drive in an event a spare has been used up by a failed disk event.
Do you know if this timeout may be modified with a specific option of the filer?
We´ve found this timeout:
netapp1-spa> options raid.timeout
raid.timeout 24 (value might be overwritten in takeover)
but this timeout does only apply when a RAID-DP has two failed disks ?
This timeout does not apply when a failed disk has no spare disk as replacement.
Don't let anyone tell you it can't be done. It might not be a good idea, but it is possible. You'll have to add the last two drives via the command line,
and nothing bad will happen after 24 hours. Here's an example: twelve one 1TB SATA drives in an FAS2020 with DataONTAP 7.3.3 nets you 7449GB usable space:
You'll need to live with the "sam.misconfig.noEligibleSpares" warning, though you can make it less annoying by setting "raid.min_spare_count". Assuming scrubbing is enabled and active, you'll need three drive failures before data is lost. Keeping a spare drive in your server closet, while not practical, would be a good idea.
BabyNetApp> aggr show_space -g
Total space WAFL reserve Snap reserve Usable space BSR NVLOG A-SIS
8276GB 827GB 372GB 7076GB 0GB 0GB
Note that you can only set min_spare_count to zero if you have RAID DP, not if you have RAID 4.