no QCOW2 on a 4.2

[Mark D]

I have used Proxmox since 2.x days. Today I installed a new machine with the latest Proxmox 4.2. I'm a bit surprised to see I only use raw disks when creating a container? I'm running this on ext4 fs.

On a different note, the server I have is a Dell PE R720 with a H710p raid controller. I wanted to use zfs, but find out that the controller does not support zfs. Should I rather create individual raid 0's for the 6 hd's rather than doing a hardware raid 50 and then doing ext4? I'm asking this cuz I guess the raw / qcow is related to fs type.

Mark

 

[LnxBil]

(We should totally have a goto-page for the LVM-thin migration related problems on the wiki....)

Your Proxmox 4.2 has LVM thin storage and therefore you have no "real" directory-based storage and hence cannot use QCOW2. Please manually (command line) add a new volume, format it with e.g. ext4 and mount it in an directory and configure it in Proxmox-GUI as a storage. Then you should be able to create QCOW2-based disks. There are tons of questions like yours already discussed in this forum, so please use the search to find possible solutions for this problem.

Concerning ZFS, your system is always capable of running ZFS if "ordinary" filesystems run perfectly. The problem is that ZFS on hardware raid works technically, but is not a good idea. ZFS works only good (with all the features they provide) on "raw" devices and so you need a passthrough-capable raid controller or a IT-firmware for the controller. Most off-the-shelf real hardware raid controller in servers are not capable of doing this, you need to replace it or try something fishy like 1:1 disk-to-raid-volume mapping etc.

 

[Mark D]

Thank you. And sorry, I did not specifically search this forum, but I did google a bit, but did not find anything. I think this should be in the FAQ.

If I have space on my hard drive, should I just go ahead and use the raw, or what would you guys do in my case?

This is a production server, running around 5 vms - light load. File/domain server, asterisk, web app, pfsense as gateway. I can easily re-do the config on my Raid controller and do a zfs. If I do that, should I go with 6 individual Raid 0, or do 2 raid 5 and then raid 1 those in zfs? I really like the features of zfs, and hate to sometimes be required to wait on ext4 to finish disk scanning. On the other hand, I notice that if I don't use the hardware raid, I don't have the easy swap out/in new hard drive to replace a failing drive.

Thanks for any suggestions!

 

[LnxBil]

Thank you. And sorry, I did not specifically search this forum, but I did google a bit, but did not find anything. I think this should be in the FAQ.

If I have space on my hard drive, should I just go ahead and use the raw, or what would you guys do in my case?

This is a production server, running around 5 vms - light load. File/domain server, asterisk, web app, pfsense as gateway. I can easily re-do the config on my Raid controller and do a zfs. If I do that, should I go with 6 individual Raid 0, or do 2 raid 5 and then raid 1 those in zfs? I really like the features of zfs, and hate to sometimes be required to wait on ext4 to finish disk scanning. On the other hand, I notice that if I don't use the hardware raid, I don't have the easy swap out/in new hard drive to replace a failing drive.

Are you running the VMs at the moment on this machine or not? If so, you already decided what storage format to use. If you're migrating to the new machine and want to stay with QCOW, you need to create a new LVM volume for your data like it was before Proxmox 4.2. If your Proxmox 4.2 install is almost clean at the moment (so no VMs), then reinstall Proxmox 4.1 and update it to Proxmox 4.2, then you have the 'old style' /var/lib/vz.

I'd only use ZFS if your controller supports IT-mode for direct access to the disks. Depending on your disks, e.g. 5 or 6 disks use zraid2 (similar to RAID6) for having two redundant disks, such that any 2 drives can fail. If you've a good and fast backup proxmox, you can also use "only" zraid1 (similar to RAID5)