Hard Disks

[shoey]

Is it possible in proxmox to say if i had two disks to store the disk images on a separate drive?

 

[tom]

pls ask more detailed.

 

[shoey]

Hi Tom,

Im building a sandybridge system with an i7 2600k and 16gb ram, what i wanted to to was to put a single hard disk and then set up a raid 10 with 3 600Gb raptors.

Is it possible to have the virtual machine disks stored on the raid array, and the proxmox os on the single disk.

 

[tom]

I still do not get your hardware details (you cannot create a raid10 with 3 disks!?) but the Proxmox VE installer just uses one disk/volume

 

[shoey]

Sorry Tom,

I was ment to say raid 5, although i may put extra disks in for this.

I know that each virtual machine would create a virtual hard disk file. I know that the installer would put the proxmox OS onto one of the hard disks.

What i want to do is have a raid array just for the Virtual hard disks of any of the machines that i choose to put onto proxmox.

Is this something that is possible? or is it just best to have a raid array an install proxmox and all of the VMs on the raid array.

 

[tom]

Take a look here: http://pve.proxmox.com/wiki/Storage_Model

I do not recommend to install the system on a single drive.

And you should always post if you just want to use KVM or just OpenVZ or both.

 

[mmenaz]

...
I do not recommend to install the system on a single drive.

I often do, when no openvz is needed, to keep the precious sas raid storge full available for kvm vm.
So I install proxmox on sata /dev/sda, and then add as lvm storage the sas rais on /dev/sdb.
You don't recomand for the risk of having a sda failure (that I don't care much, I can replace the HD and reinstall proxmox in half an hour) or there are more subtle issues I'm not aware of?
Performances seem good so far, don't relly know if proxmox itself does too much I/O in certain conditions so sata could bring performances of the whole system down (do you think so?).
If proxmox 2 will let the installation not take the whole storage for "local lvm" storage I will happily skip this "split" installation and have everything on sas raid and still have the lvm storage feature of a LV for each VM.

 

[dswartz]

I agree with you, mmenaz. There are times when fault tolerance for disks is not a concern. My proxmox box has one single PATA drive. I don't care if it dies, as I have vzdump backups of the VMs, and each VM is also backed up every night, so the most I can lose is 1 day of changes (which is fine with me...)

 

[dietmar]

Performances seem good so far, don't relly know if proxmox itself does too much I/O in certain conditions so sata could bring performances of the whole system down (do you think so?).

No, normally not (as long as you do not make a vzdump backup to that location).

 

[hverbeek]

I was ment to say raid 5, although i may put extra disks in for this.

I would recommend against RAID5 and for RAID10 for performance reasons (especially write performance).

 

[dswartz]

Well, as always, there is a tradeoff. RAID1/10 do cost half your space, but I have to admit RAID10 performance is nice