pve-storage-zfs.adoc

   1 [[storage_zfs]]
   2 ZFS over ISCSI Backend
   3 ----------------------
   4 ifdef::wiki[]
   5 :pve-toplevel:
   6 :title: Storage: ZFS over ISCSI
   7 endif::wiki[]
   8
   9 Storage pool type: `zfs`
  10
  11 This backend accesses a remote machine having a ZFS pool as storage and an iSCSI
  12 target implementation via `ssh`. For each guest disk it creates a ZVOL and,
  13 exports it as iSCSI LUN. This LUN is used by {pve} for the guest disk.
  14
  15 The following iSCSI target implementations are supported:
  16
  17 * LIO (Linux)
  18 * IET (Linux)
  19 * ISTGT (FreeBSD)
  20 * Comstar (Solaris)
  21
  22 NOTE: This plugin needs a ZFS capable remote storage appliance, you cannot use
  23 it to create a ZFS Pool on a regular Storage Appliance/SAN
  24
  25
  26 Configuration
  27 ~~~~~~~~~~~~~
  28
  29 In order to use the ZFS over iSCSI plugin you need to configure the remote
  30 machine (target) to accept `ssh` connections from the {pve} node. {pve} connects to the target for creating the ZVOLs and exporting them via iSCSI.
  31 Authentication is done through a ssh-key (without password protection) stored in
  32 `/etc/pve/priv/zfs/<target_ip>_id_rsa`
  33
  34 The following steps create a ssh-key and distribute it to the storage machine
  35 with IP 192.0.2.1:
  36
  37 ----
  38 mkdir /etc/pve/priv/zfs
  39 ssh-keygen -f /etc/pve/priv/zfs/192.0.2.1_id_rsa
  40 ssh-copy-id -i /etc/pve/priv/zfs/192.0.2.1_id_rsa.pub root@192.0.2.1
  41 ssh -i /etc/pve/priv/zfs/192.0.2.1_id_rsa root@192.0.2.1
  42 ----
  43
  44 The backend supports the common storage properties `content`, `nodes`,
  45 `disable`, and the following ZFS over ISCSI specific properties:
  46
  47 pool::
  48
  49 The ZFS pool/filesystem on the iSCSI target. All allocations are done within that
  50 pool.
  51
  52 portal::
  53
  54 iSCSI portal (IP or DNS name with optional port).
  55
  56 target::
  57
  58 iSCSI target.
  59
  60 iscsiprovider::
  61
  62 The iSCSI target implementation used on the remote machine
  63
  64 comstar_tg::
  65
  66 target group for comstar views.
  67
  68 comstar_hg::
  69
  70 host group for comstar views.
  71
  72 lio_tpg::
  73
  74 target portal group for Linux LIO targets
  75
  76 nowritecache::
  77
  78 disable write caching on the target
  79
  80 blocksize::
  81
  82 Set ZFS blocksize parameter.
  83
  84 sparse::
  85
  86 Use ZFS thin-provisioning. A sparse volume is a volume whose
  87 reservation is not equal to the volume size.
  88
  89
  90 .Configuration Examples (`/etc/pve/storage.cfg`)
  91 ----
  92 zfs: lio
  93    blocksize 4k
  94    iscsiprovider LIO
  95    pool tank
  96    portal 192.0.2.111
  97    target iqn.2003-01.org.linux-iscsi.lio.x8664:sn.xxxxxxxxxxxx
  98    content images
  99    lio_tpg tpg1
 100    sparse 1
 101
 102 zfs: solaris
 103    blocksize 4k
 104    target iqn.2010-08.org.illumos:02:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx:tank1
 105    pool tank
 106    iscsiprovider comstar
 107    portal 192.0.2.112
 108    content images
 109
 110 zfs: freebsd
 111    blocksize 4k
 112    target iqn.2007-09.jp.ne.peach.istgt:tank1
 113    pool tank
 114    iscsiprovider istgt
 115    portal 192.0.2.113
 116    content images
 117
 118 zfs: iet
 119    blocksize 4k
 120    target iqn.2001-04.com.example:tank1
 121    pool tank
 122    iscsiprovider iet
 123    portal 192.0.2.114
 124    content images
 125 ----
 126
 127 Storage Features
 128 ~~~~~~~~~~~~~~~~
 129
 130 The ZFS over iSCSI plugin provides a shared storage, which is capable of
 131 snapshots. You need to make sure that the ZFS appliance does not become a single
 132 point of failure in your deployment.
 133
 134 .Storage features for backend `iscsi`
 135 [width="100%",cols="m,m,3*d",options="header"]
 136 |==============================================================================
 137 |Content types  |Image formats  |Shared |Snapshots |Clones
 138 |images         |raw            |yes    |yes        |no
 139 |==============================================================================