Raid 1+0 with incongruous drives

[Taraka_1]

I have two HP DL380 G4 Servers that where initially setup in 1+0 raid configuration but only had 2 x 146 GB Drives each. Later two more 300 GB drives where purchased and put in each system.

I want to utilize all the space possible but I need to move some drives around. My systems currently setup looks like this:

System 1: slot 0 & 1 have 146 GB Drives; slots 2 & 3 have 300 GB Drives.

System 2: Slots 0 & 1 have 146 GB Drives; slots 2 & 3 have 300 GB Drives.

I would like to move all the 146 GB drives to System 1 and all the 300 GB drives to system 2.

My question is: What will happen if I swap these drives around and will the raid rebuild on the disks previously from another system?

Thanks!

[Mi6t0]

Originally the raid information stays in the RIS part of the HDDs.

If you don't want to loose some information or to avoid rebuilds, swap the HDDs in pairs :) Just pull out HDDs 2 and 3 and change them with the two disks from the other servers.

Note that both servers have to use the same controller.

Regards

[Taraka_1]

Thank you for the response. Both systems have identical hardware with a 6i controller.

If I remove the two 300 GB drives from system 1 and place them in system 2 in slots 0 & 1 (which replaces the 146 GB drives) the drives will funtion properly? Will I be able to see all 300 GB of space given that the original drives where only 146 GB? It will rebuild from the original drives and not the two I pulled from the other system, correct? I don't want to end up with two identical system :)

[Mi6t0]

Well the idea of moving the drives in pairs is to avoid the rebuild process.

But... I am not sure - are all the 4 HDDs a part of the array ot you have a seperate array for every HDD pair. The scenario that I advised will work if you have array per every HDD-pair. In this case you won't have troubles.

Can you tell how your array is configured?

[KarloChacon]

hi

yes what is the RAID configuration in system 1 and 2? two RAID 1+0?

I suppose 146 HDDs have the boot (OS) for this servers?

I mean if you just swap HDDs what of the server won't have OS and I don't know about the amount of data but data from 300 GB won't fit 146 GB

Regards

[Taraka_1]

Both systems are setup raid 1+0 with all 4 drives as part of a single array. From what I understand the 6i controller has a single channel and limits me to a single array.

Initially, each system had just the two 146GB drives and where setup as raid 1+0. When the four 300GB drives where added to both systems (two per box) they could only be added to the existing array. What this did was give me a total of 300 GB of space per box even though I had 2x146 & 2x300GB per system.

At the time we didn't realize that we had only a single array channel to work with. So I can only think of one way to utilize all the space these drives offer and that is to combine all the 146GB drives in system 1 and all the 300 drives in system 2. But... I want to do this without losing either system.

System 1 will probably be easy. The two 146 drives in slots 0 & 1 will remain, pull the two 300 drives out and replace them with the 146 drives from system two. add them to the array and off I go.. I think?

System two will be left with two 300 drives in slot 2 & 3 as the two 146 will be pulled and placed in system 1. At this point, what can I do with system 2? Can I move the 300 drives to slot 0 & 1, recover all the 300 GB of space in the array then add the other two 300 drives?

I apologize if I am not making much sense.