How can I use hotspare Disk in RAID1

bipinkdas · 07-06-2009, 07:41 AM

Hello everybody

I have server with 3 harddisk of 300Giga. I have did it with RAID1 and the third harddisk as a hotspare. My /var partition is 200Giga and the hotspare is 300GB. How can I extend my /var with this Hotspare ?

Thanks in advance.

nowonmai · 07-06-2009, 08:45 AM

I'm assuming your RAID 1 consists of 2x300GB drives and there is one hotspare of 300GB?
You can't just insert another 300GB into a RAID 1. If you had another, you could configure a second RAID 1 and if you had used LVM in our original partitioning scheme, you could grow your LVM by this 300GB.

gael · 07-06-2009, 11:48 AM

The reason why you have a hot spare is in the case of a failure of one of the 2 disks in the RAID1 mirror. So do not use it or you will break the fail over it provides.

Instead, you can configure another RAID10 by adding 2 x 300GB disks. Or as suggested nowonmai, add 1 disk and do another RAID1 but in this case you are losing the benefits of the hot spare.

cyclegar · 07-06-2009, 02:35 PM

Hot spares for not for use with existing volumes.

This disk only is a backup disk for the 2 disks used in the volume.

it will kick in only if one of the disks fails and takes the failed disks position on the raid.

You cannot use a hot spare on an existing volume , to use a hot spare you need to remove it as a hot spare first before being used.

Once removed there wont be any host spare disk for failures.

Thanks
MC

GrapefruiTgirl · 07-06-2009, 03:48 PM

Moved: This thread is more suitable in Hardware and has been moved accordingly to help your thread/question get the exposure it deserves.