NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
Disc failure during expansion
Hi all.
I have been running a ReadyNAS with 3 drives in for a while, (2+2+4 Gig respectively). I ended up with 3.6TB of capacity, and hit 80%+ full the other day.
Accordingly, I put an 8Gig drive into the 4th slot the other day, and let it reshape.
Sadly, during the reshape, disc 2 died. So I removed that drive, let the reshape continue, and it all seemed to recover.
I now have a setup with:
Disc 1 = 2 TB
Disc 3 = 4 TB
Disc 4 = 8 TB.
It's telling me that the data is non-redundant (which kind of makes sense), but is still only telling me I have 3.6TB free.
I reckon that setup should be capable of giving me ~6TB redundant data.
Is there anything I can do to actually get the proper size and to restore the data redundancy please? (Preferably without having to buy another new disc, immediately!)
Thanks in advance for any help.
robinwatts wrote:
If I had an array with 4+8+8, could I safely add another 4TB drive later to get it to the maximum 16?
The usual guidance is that you can only add 8 TB (or bigger). Taking the expansion limits into account, that means upgrading the 4 TB to 8 TB.
Some experiments posted here show that OS-6 NAS would let you add a 4 TB (since there is a 4 TB already in the array). However, I don't know if OS 5 will allow that (though it is technically possible).
Under the covers, a 4+8+8 setup has two RAID groups - a 3x4TB RAID-5 group that covers all drives, and a 2x4 RAID-1 group that covers the two larger drives. These are assembled into one volume.
Adding a 2 TB drive requires that the 3x4TB group be split into two 3x2TB groups (followed by adding the new drive to one of those groups). XRAID won't split an existing group that way (and I don't think it can be done easily w/o data loss).
16 Replies
The only ways to restore redundancy are to
- add another disk. (either 2 TB or 8 TB).
- or do a factory reset and restore data from backup.
I do recommend creating/updating your backup in this situation, since another disk failure will result in loss of all your data.
Your disk setup does waste space (with single redundancy the two largest disks should be the same size).
If I add another disc (say, another 8TB one), will that give me the expected amount of space? (i.e. at least 10TB redundant storage)?
Thanks.
The rule for single-redundancy XRAID (what you have) is "sum the disks and subract the largest".
So with 2TB + 4TB + 8TB + 8 TB you'll get 14 TB of redundant storage. The NAS reports TiB, so it will say ~12.7. (TB: 1000*1000*1000*1000 bytes; TiB:1024*1024*1024*1024 bytes).
If your 2 TB drive hadn't failed, you'd have had 2TB + 2 TB + 4 TB + 8 TB. That would have given you 8 TB (~7.3 TiB).
NETGEAR Academy
Boost your skills with the Netgear Academy - Get trained, certified and stay ahead with the latest Netgear technology!
Join Us!
