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=Introduction=
<!--PVE_IMPORT_START_MARKER-->
tbd. (running zfs on Proxmox VE is not officially supported)
<!-- Do not edit - this is autogenerated content -->
 
{{#pvedocs:pve-storage-zfspool-plain.html}}
=Native ZFS for Linux on Proxmox =
[[Category:Reference Documentation]]
 
<pvehide>
2013-03-27:  0.6.1  ZFSOnLinux (ZoL) is now ready for wide scale deployment on everything from
Storage pool type: zfspool
desktops to super computers. [https://groups.google.com/a/zfsonlinux.org/group/zfs-announce/topics?lnk See announcement]
This backend allows you to access local ZFS pools (or ZFS file systems
 
inside such pools).
check  http://zfsonlinux.org/ See the Documentation and Community Resources for more information and help.
Configuration
 
The backend supports the common storage properties content, nodes,
 
disable, and the following ZFS specific properties:
== using  Debian Wheezy packages from zfsonlinux  ==
pool
For PVE on Wheezy [ 3.0+ ].
Select the ZFS pool/filesystem. All allocations are done within that
 
pool.
2013-05-29 - ''Debian Packages  DKMS style packages for Debian are available from the zfsonlinux.org repository. These packages track the latest official upstream tag and are refreshed as new releases are made available''  from  http://zfsonlinux.org/debian.html  . 
blocksize
 
Set ZFS blocksize parameter.
also check http://pthree.org/2012/04/17/install-zfs-on-debian-gnulinux/
sparse
 
Use ZFS thin-provisioning. A sparse volume is a volume whose
*If you are upgrading from the Ubuntu PPA method remove ubuntu packages first.
reservation is not equal to the volume size.
aptitude remove ubuntu-zfs
mountpoint
 
The mount point of the ZFS pool/filesystem. Changing this does not
*If this is a new install or you are repeating a previously failed attempt
affect the mountpoint property of the dataset seen by zfs.
dpkg --purge zfsonlinux zfsutils libzfs1 zfs-dkms dkms
Defaults to /&lt;pool&gt;.
 
Configuration Example (/etc/pve/storage.cfg)
:move the old zfs.list from /etc/apt/sources.list.d
zfspool: vmdata
*make sure pve headers are installed. if not :
        pool tank/vmdata
aptitude install pve-headers-$(uname -r)
        content rootdir,images
 
        sparse
*I think the ln is still needed.
File naming conventions
ln -s /lib/modules/$(uname -r)/build /lib/modules/$(uname -r)/source
The backend uses the following naming scheme for VM images:
 
vm-&lt;VMID&gt;-&lt;NAME&gt;      // normal VM images
:then follow instructions from http://zfsonlinux.org/debian.html , i copied here , but check link in case these changed:
base-&lt;VMID&gt;-&lt;NAME&gt;    // template VM image (read-only)
<pre>
subvol-&lt;VMID&gt;-&lt;NAME&gt;  // subvolumes (ZFS filesystem for containers)
su -
&lt;VMID&gt;
wget http://archive.zfsonlinux.org/debian/pool/main/z/zfsonlinux/zfsonlinux_1%7Ewheezy_all.deb
This specifies the owner VM.
dpkg -i zfsonlinux_1~wheezy_all.deb
&lt;NAME&gt;
apt-get update
This can be an arbitrary name (ascii) without white space. The
apt-get install debian-zfs
backend uses disk[N] as default, where [N] is replaced by an
</pre>
integer to make the name unique.
 
Storage Features
you should see zfs and spl module builds...    check if OK
ZFS is probably the most advanced storage type regarding snapshot and
<pre>
cloning. The backend uses ZFS datasets for both VM images (format
# ls -l /lib/modules/$(uname -r)/updates/dkms/
raw) and container data (format subvol). ZFS properties are
total 3128
inherited from the parent dataset, so you can simply set defaults
-rw-r--r-- 1 root root  340944 May 29 10:25 splat.ko
on the parent dataset.
-rw-r--r-- 1 root root  302104 May 29 10:25 spl.ko
Table 1. Storage features for backend zfs
-rw-r--r-- 1 root root  13392 May 29 10:27 zavl.ko
Content types
-rw-r--r-- 1 root root  71232 May 29 10:27 zcommon.ko
Image formats
-rw-r--r-- 1 root root 1935120 May 29 10:27 zfs.ko
Shared
-rw-r--r-- 1 root root  130408 May 29 10:27 znvpair.ko
Snapshots
-rw-r--r-- 1 root root  40424 May 29 10:27 zpios.ko
Clones
-rw-r--r-- 1 root root  330368 May 29 10:27 zunicode.ko
images rootdir
</pre>
raw subvol
 
no
TBD:
yes
:test the above again and update the instructions as necessary.  
yes
:does dkms auto build modules when pve kernel is upgraded?  for that to happen headers would need to be installed and the ln may be needed.
Examples
 
It is recommended to create an extra ZFS file system to store your VM images:
== kernel upgrade  ==
# zfs create tank/vmdata
currently this needs to be done when a kernel upgrade occurs. 2014-01-26
To enable compression on that newly allocated file system:
*'''before reboot''':
# zfs set compression=on tank/vmdata
#install pve-headers
You can get a list of available ZFS filesystems with:
#make a symlink
# pvesm zfsscan
#make spl and zfs modules for new kernel.
See Also
this is an example,  replace the xx with new pver kernel number. and there is probably a grep/sed or some way to put the kernel version in the following..
Storage
aptitude install pve-headers-2.6.32-99-pve
ZFS on Linux
ln -s /lib/modules/2.6.32-99-pve/build /lib/modules/2.6.32-99-pve/source
</pvehide>
 
<!--PVE_IMPORT_END_MARKER-->
*this will force modules to be  built ( there is probably a better way to do this , as all kernels get their zfs and spl modules rebuilt, and we just need the new kernel modules... ).
aptitude reinstall spl-dkms  zfs-dkms
 
==Creating Pools and Filesystems==
'''see Install on a high performance system''' for suggestions on creating pool.   I'd set up alias for each disk to make looking at commands like this and zfs status reports easier.'''
 
<pre>
zpool create -f tank -o ashift=12 raidz2 scsi-1AMCC_F310KNWD4989B600434A  \
scsi-1AMCC_F310WSKD4989B6001C42 scsi-1AMCC_F31122MD4989B6009010 \
scsi-1AMCC_F312LZKD4989B600445E scsi-1AMCC_F312XYYD4989B600DB04 \
scsi-1AMCC_F312ZWBD4989B600B860 scsi-1AMCC_F314VEDD4989B600F2F0 \
scsi-1AMCC_Y38318404989B6000158 scsi-1AMCC_Z240WX6XB8C465007F42 \
scsi-1AMCC_Z340BGN3B9782E00EC8E scsi-1AMCC_Z340BHW7B8C47900D174 \
scsi-1AMCC_Z340BJ880001D10074A4 scsi-1AMCC_Z340BJSPB8C456001B6A \
scsi-1AMCC_Z340BK0L0001CC00DE3A scsi-1AMCC_Z340BM4Z0001D1003858 \
scsi-1AMCC_Z340BPWDB8C488001BC8 \
log scsi-3600050e000017c000a9c000092fd0000 \
cache scsi-3600050e000017c0075c000000ad50000
</pre>
 
*atime
zfs set atime=off tank
 
==Create directories and mount points==
<pre>
zfs create tank/data
zfs set mountpoint=/data tank/data
 
zfs create tank/pve
zfs set mountpoint=/pve tank/pve
 
zfs create tank/bkup
zfs set mountpoint=/bkup tank/bkup
</pre>
 
==destroy==
to start over
zpool destroy zfs-pool
 
==Setting Properties==
*atime
zfs set atime=off tank
 
*Automatically NFS-export all home directories  [ I do not know how to use zfs nfs yet , or if it works yet in linux...].
zfs set sharenfs=rw tank/home
*check sharenfs 
<pre>
zfs get sharenfs tank/home
NAME    PROPERTY  VALUE    SOURCE
tank/home  sharenfs  rw        local
</pre>
*Turn on compression for everything in the pool
zfs set compression=on tank
 
== kvm tuning==
see thread on prox forum , per user Nemesiz  :
*pool:
zfs set primarycache=all tank
*kvm config:
* change cache to Write Back
:You can do it using web GUI or manually. Example:
ide0: data_zfs:100/vm-100-disk-1.raw,cache=writeback
if not set this happened:
<pre>
qm start 4016
kvm: -drive file=/data/pve-storage/images/4016/vm-4016-disk-1.raw,if=none,id=drive-virtio1,aio=native,cache=none: could not open disk image /data/pve-storage/images/4016/vm-4016-disk-1.raw: Invalid argument
</pre>
== Install on a high performance system==
 
As of 2013 high performance servers have 16-64 cores, 256GB-1TB RAM and potentially many 2.5" disks and/or a PCIe based SSD with half a million IOPS. High performance systems benefit from a number of custom settings, for example enabling compression typically improves performance.
 
* If you have a good number of disks keep organized by using aliases. Edit /etc/zfs/vdev_id.conf to prepare aliases for disk devices found in /dev/disk/by-id/ :
# run 'udevadm trigger' after updating this file
alias a0        scsi-36848f690e856b10018cdf39854055206
alias b0        scsi-36848f690e856b10018cdf3ce573fdeb6
alias a1        scsi-36848f690e856b10018cdf40f5b277cbc
alias b1        scsi-36848f690e856b10018cdf43a5db1b99b
alias a2        scsi-36848f690e856b10018cdf4575f652ad0
alias b2        scsi-36848f690e856b10018cdf47761587cec
 
Use flash for caching/logs. If you have only one SSD, use cfdisk to create a small partion for the ZIL (ZFS intent log) and a larger one for the L2ARC (ZFS read cache on disk). Make sure that the ZIL is on the first partition.  In our case we have a Express Flash PCIe SSD with 175GB capacity and setup a ZIL with 25GB and a L2ARC cache partition of 150GB
 
* edit /etc/modprobe.d/zfs.conf​ to apply several tuning options for high performance servers:
 
# ZFS tuning for a proxmox machine that reserves 64GB for ZFS
#
# Don't let ZFS use less than 4GB and more than 64GB
options zfs zfs_arc_min=4294967296
options zfs zfs_arc_max=68719476736
#
# disabling prefetch is no longer required
options zfs l2arc_noprefetch=0
 
* create a zpool of striped mirrors (equivalent to RAID10) with log device and cache and always enable compression:
 
zpool create -o compression=on -f tank mirror a0 b0 mirror a1 b1 mirror a2 b2 log /dev/rssda1 cache /dev/rssda2​
 
* ​​​​​​​​check the status of the newly created pool:
 
<pre>
root@proxmox:/# zpool status
  pool: tank
state: ONLINE
  scan: none requested
config:
 
        NAME        STATE    READ WRITE CKSUM
        tank        ONLINE      0    0    0
          mirror-0  ONLINE      0    0    0
            a0      ONLINE      0    0    0
            b0      ONLINE      0    0    0
          mirror-1  ONLINE      0    0    0
            a1      ONLINE      0    0    0
            b1      ONLINE      0    0    0
          mirror-2  ONLINE      0    0    0
            a2      ONLINE      0    0    0
            b2      ONLINE      0    0    0
        logs
          rssda1    ONLINE      0    0    0
        cache
          rssda2    ONLINE      0    0    0
 
errors: No known data errors
</pre>
 
Using PVE 2.3 on a 2013 high performance system with ZFS you can install Windows Server 2012 Datacenter Edition with GUI in just under 4 minutes.
 
=zfs links and docs=
*http://zfsonlinux.org/faq.html
 
*http://hub.opensolaris.org/bin/download/Community+Group+zfs/docs/zfslast.pdf
 
and this has some very important information to know before implementing zfs on a production  system.
*http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide
 
check these well written manual pages:
man zfs
man zpool
 
= How to install ZFS-fuse under Proxmox =
 
(Tested with Kernel 2.6.32)
 
  apt-get install build-essential libaio-dev libattr1-dev libacl1-dev libz-dev libz-dev libfuse-dev libfuse2 scons libssl-dev
  wget -nd http://zfs-fuse.net/releases/0.6.0/zfs-fuse-0.6.0.tar.bz2
  tar jxvf zfs-fuse-0.6.0.tar.bz2
  cd zfs-fuse-0.6.0
  cd src
  scons
  scond install
 
'''Note:''' zfs-fuse-0.6.0 is now (Dec 2012) deprecated. Use [http://zfs-fuse.net/releases/0.7.0/zfs-fuse-0.7.0.tar.bz2 zfs-fuse-0.7.0.tar.bz2] instead.
 
Fire up ZFS-fuse daemon
  /usr/local/sbin/zfs-fuse
 
Create Zpool
  zpool create -m /var/lib/vz/images2 /dev/sdb
 
Create ZFS
  zfs create images2/109
 
ZFS clone a vm 109 to vm 110
  zfs snapshot images2/109@master
  zfs clone images2/109@master images2/110
 
=zfs mounting workaround =
'''The default zfs mount -a script runs too late in the boot process for most system scripts. The following make zfs mounts start on time. '''
 
2014-01-22  the info below came from this excellent wiki page: http://wiki.complete.org/ConvertingToZFS
 
*Edit /etc/default/zfs and set ZFS_MOUNT='yes'
 
*edit /etc/insserv.conf,
:and at the end of the $local_fs line,
:add zfs-mount (without a plus).
 
edit /etc/init.d/zfs-mount and find three lines near the top, changing them like this:
<pre>
# Required-Start:
# Required-Stop:
# Default-Start: S
</pre>
''note remove the Required-Start and -Stop entries.''
 
 
*Activating init.d changes Then run:
<pre>
insserv -v -d zfs-mount
</pre>
 
I had an issue with pve storage on zfs, before pve would start before zfs and create directories at the zfs mount point. to fix that start single user mode and remove the directories [ make sure  they are empty.... ].
 
also see https://github.com/zfsonlinux/pkg-zfs/issues/101

Latest revision as of 08:08, 6 December 2019

Storage pool type: zfspool

This backend allows you to access local ZFS pools (or ZFS file systems inside such pools).

Configuration

The backend supports the common storage properties content, nodes, disable, and the following ZFS specific properties:

pool

Select the ZFS pool/filesystem. All allocations are done within that pool.

blocksize

Set ZFS blocksize parameter.

sparse

Use ZFS thin-provisioning. A sparse volume is a volume whose reservation is not equal to the volume size.

mountpoint

The mount point of the ZFS pool/filesystem. Changing this does not affect the mountpoint property of the dataset seen by zfs. Defaults to /<pool>.

Configuration Example (/etc/pve/storage.cfg)
zfspool: vmdata
        pool tank/vmdata
        content rootdir,images
        sparse

File naming conventions

The backend uses the following naming scheme for VM images:

vm-<VMID>-<NAME>      // normal VM images
base-<VMID>-<NAME>    // template VM image (read-only)
subvol-<VMID>-<NAME>  // subvolumes (ZFS filesystem for containers)
<VMID>

This specifies the owner VM.

<NAME>

This can be an arbitrary name (ascii) without white space. The backend uses disk[N] as default, where [N] is replaced by an integer to make the name unique.

Storage Features

ZFS is probably the most advanced storage type regarding snapshot and cloning. The backend uses ZFS datasets for both VM images (format raw) and container data (format subvol). ZFS properties are inherited from the parent dataset, so you can simply set defaults on the parent dataset.

Table 1. Storage features for backend zfs
Content types Image formats Shared Snapshots Clones

images rootdir

raw subvol

no

yes

yes

Examples

It is recommended to create an extra ZFS file system to store your VM images:

# zfs create tank/vmdata

To enable compression on that newly allocated file system:

# zfs set compression=on tank/vmdata

You can get a list of available ZFS filesystems with:

# pvesm zfsscan