Drobo

Had drobo working fine, upgraded a drive, now 2 volumes?

I had a drobo with 500Gb drives and it ran out of space, so I upgraded the 500Gb drives to 1TB drives.
When I inserted the first drive, Drobo asked me to format the drive - I said ok and eventually drobo admin detected the drive and according to dashboard I had extra space.
But it appears to have created an additional volume on my Drobo, as opposed to expand my previous volume to reflect the space.
I don’t want a multiple volumes. How can i get this without losing all my data?

thanks!

this is because when you FIRST got drobo - you picked a volume size (i guess 2TB - the default).

now your physical hard disk space is greater than your volume size, so it has created an additional 2Tb volume so that you can utilise your additional space.

The only way back from this is to wipe drobo and start again with a larger volume size (say 16TB for instance). then drobo would not create a second volume until you had over 16TB of disks in it - something which is not currently possible.

This is called thin provisioning.

DRI do talk about this very clearly in the manual which came with drobo and also on their support pages.

incidentally drobo did NOT ask you to format the drive you had just inserted… it did that automatically and then added it to your storage pool - it was asking you to format the new volume it had automatically created for you so that you could take advantage of the additional space you now have.

i hope this makes things clearer.

the short answer: drobo cannot extended volumes. if your put in more disk space than your current volume - drobo has not make another volume. to avoid this - pick large volumes to begin with!

Sorry i cant be more help :([hr]
this is the article i found on the drobo support site in under 5 seconds of searching for the term “additional volumes”

http://support.datarobotics.com/app/answers/detail/a_id/23

follow on question: and this relates to the mess being created by apple’s time machine sparse bundle saga.

it sounds like Drobo allows me to create more than one volume. so if my first volume is 1TB, can i create a second volume for 16TB? if say in terms of actual hdd space, i slot in 2x1.5TB of hard disk so i should have something like 500MB left over, then anything additional hard disk that i insert will contribute space to the second volume and not the first?

is there any limit to the total number of volumes to be created on a Drobo (2nd generation)?

the free space is shared between volumes there is no concept of allocation

for instance

if you had 5 Tb of hard disk space and four 16 tb volumes… if you were to put 1 tb on each volume… then you could put one more tb (to take you up to 5) on ANY of those 4 volumes

it hope that makes it clearer[hr]
as for the limit - i think it is 16 (that si the limit on the bigger drobo’s and i dont see why they would change it)