4.4 install to ZRAID10

MimCom

Active Member
Apr 22, 2011
204
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Southwest NM
Four 2TB HGST 7K6000 4Kn SATA drives selected for ZFS RAID10 in Proxmox installer. Installer fails at the end with an unable to mount zfs dialog box. [ctrl] + [alt] + F2 shows:

Unable to install the i386-pc boot loader on '/dev/sda'
umount: /rpool/ROOT/pve-1/var/lib/vz: not mounted
umount: /rpool/ROOT/pve-1: target is busy
umount:/rpool/ROOT: target is busy
cannot unmount '/rpool:ROOT': umount failed
umount: /rpool: target is busy
cannot unmount '/rpool': umount failed
 
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Is there some kind of problem with ZFS install in general? I'm getting the same failure on every ZFS configuration I've tried (RAID0 and RAID1, even using different pairs of disks and also RAID-Z1 using all four.)
 
I'm curious if Proxmox uses zfs-fuse or is there a kernel module? I have not been able to discern this from the documentation or in forum posts.

Also, with ZFS on root, does the boot record get written to multiple drives?
 
Hi mhotel, proxmox uses zfsonlinux. You should first clean you hd's (take a linux live system). Then try again.
cu peje
 
Thank you, that helps. Has anyone else succeeded installing 4.2 with ZFS on bare metal? How about a zfsonlinux + Jessie livecd?
 
Hi,
do you use a Raid controller?
 
Hello mhotel,

Now I have exact the same problem with the up to date proxmox 4.3 Installer.
- Four 2TB HGST 7K6000 4Kn SATA straight on the Fujitsu D3417-B Mainboard (without a raid controller) the HGST drives are factory new (4Kn also known as "Advanced Format disks")
- as Install Option I select ZFS-Raid10
- the installer works until 100%, after "make disk bootable" and then

"Installation failed" ... " "unable to umount zfs"
I try it with an USB Stick an with a boot CD, always with the same result.

Is there a solution for this problem?

@mhotel: can you change the thread title from 4.2 to "4.2 and 4.3"?
 
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Hello mhotel,

Now I have exact the same problem with the up to date proxmox 4.3 Installer.
- Four 2TB HGST 7K6000 4Kn SATA straight on the Fujitsu D3417-B Mainboard (without a raid controller) the HGST drives are factory new (4Kn also known as "Advanced Format disks")
- as Install Option I select ZFS-Raid10
- the installer works until 100%, after "make disk bootable" and then

"Installation failed" ... " "unable to umount zfs"
I try it with an USB Stick an with a boot CD, always with the same result.

Is there a solution for this problem?

@mhotel: can you change the thread title from 4.2 to "4.2 and 4.3"?
Hi maxprox,
this is an know bug with 4k blocksize: https://bugzilla.proxmox.com/show_bug.cgi?id=1211

Udo
 
Hi Udo, and kotakomputer,

thanks for the answers.
Sorry but I do not understand exactly how can I workaround.
If I understand the "Bugzilla – Bug 1211" correct, I have to install Debian Jessie first....
First I explain my goal:
I buy specifically this HGST 7K6000 4Kn(!) because I think this are for now one of the fastest and most reliable SATA Server Drives.
With four of them I will build a software raid 10. And the best solution with proxmox was for it a zfs raid 10.
Is there one way to implement this? Or a good alternative?
Is it possible to do it with install Debian jessie first, build a zfs raid 10 and then install proxmox?

@kotakomputer
You should first clean you hd's (take a linux live system). Then try again.
cu peje
My Server together with the four HGST drives are factory new. I can't see what you mean.

And what about the alternative btrfs?
Is there a way and maybe a how-to for proxmox with btrfs and raid 10?

best regards,
maxprox
 
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the proxmox installer does not support ZFS+EFI (at the moment, because the EFI partition is a single point of failure because Grub does not support updating the redundant copies), so if you need to boot using UEFI you need to either use something other than ZFS, or install Debian Jessie with root on ZFS (using debootstrap and ZFS from jessie-backports) and upgrade to PVE. you should really know what you are doing if you attempt to do that!

I have some ideas on how to tackle the EFI partition problem, but those will require some time to implement and test (and ideally go into upstream Grub).

The 4Kn problem is totally unrelated to ZFS, except that AFAICT 4Kn disks are only bootable in UEFI mode.
 
Is there some kind of problem with ZFS install in general? I'm getting the same failure on every ZFS configuration I've tried (RAID0 and RAID1, even using different pairs of disks and also RAID-Z1 using all four.)

After a failed ZFS install from the Proxmox installer, I think you need to clear ZFS information from the disk before trying again, or it'll never work. There's not a huge amount of info about the error in the installer - and I've never managed to get one to a shell prompt to examine/fix anything, but I think that's what is going on.

Zap the ZFS signatures in the filesystem partitions (dd'ing the first/last 5MB in each should get it). Clearing the partition table alone isn't enough. If you had a full system, you could probably use "zfs labelclear". I have an Arch ISO with a full ZFS install that I sometimes use for ZFS maintenance like this.

I've never had a Proxmox RAID10 install work for me, IIRC. But I've done at least 8 Proxmox installs to an initial 2-disk RAID0 stripe - which always works fine with "clean" disks, modulo the partition table/grub partitions need attention afterwards - see my post about grub-2.02pve5.

And then I convert the pool to RAID10 once I've got the partitions to my liking.
 
...

The 4Kn problem is totally unrelated to ZFS, except that AFAICT 4Kn disks are only bootable in UEFI mode.

and
spudger said:
After a failed ZFS install from the Proxmox installer, I think you need to clear ZFS information from the disk before trying again, or it'll never work.
If I understand both correct, It will be a solution for me, to take a suitable M.2 SSD for this Mainboard, install proxmox, with ext4 on it and for legacy boot, after it I clean the four 4kn drives with:
Code:
zfs labelclear
and build my requested Raid 10 on it.
Is it correct?

regards
maxprox
 
if you don't want to boot from the raid10 zpool, but just want to use it as storage, that should work without problems.
 
4Kn drives only boot in UEFI? I could have sworn the hybrid Seagate 1TB I stuck in my laptop 18 months ago reported a 4K sector size and booted entirely as expected from legacy BIOS/MBR. Sorry if I misunderstood.

Sometimes the drive lies. My Samsung 850 SSD's report 512 bytes as sector size. lol; yeh, right... Use a pool with shift=12 regardless for those.
 
4Kn drives only boot in UEFI? I could have sworn the hybrid Seagate 1TB I stuck in my laptop 18 months ago reported a 4K sector size and booted entirely as expected from legacy BIOS/MBR. Sorry if I misunderstood.

Sometimes the drive lies. My Samsung 850 SSD's report 512 bytes as sector size. lol; yeh, right... Use a pool with shift=12 regardless for those.

we don't have any "real" 4Kn drives in our test lab (at the moment) - only ones that use 4K sectors internally, but report 512b sectors to the OS (i.e., "512e" drives). I found many reports stating that 4Kn drives are not supported on most BIOS implementations (512e, which most modern drives use, is no problem there).
 
The 4Kn problem is totally unrelated to ZFS, except that AFAICT 4Kn disks are only bootable in UEFI mode.

okay,
this was a new information for me. Now I test it with only one of the 4Kn drives. I Installed a Debian Jessie with ext4 mostly in the default options, and you are right: from this hard disc, Debian can not boot in legacy mode
as I said, I did not know that.

if you don't want to boot from the raid10 zpool, but just want to use it as storage, that should work without problems.

okay, thank you , I will give it a try
maxprox
 

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