pvecm: fix wrong quorum numbers

[pve-docs.git] / pve-storage-iscsi.adoc

[[storage_open_iscsi]]
Open-iSCSI initiator
--------------------
ifdef::wiki[]
:pve-toplevel:
:title: Storage: iSCSI
endif::wiki[]

Storage pool type: `iscsi`

iSCSI is a widely employed technology used to connect to storage
servers. Almost all storage vendors support iSCSI. There are also open
source iSCSI target solutions available,
e.g. http://www.openmediavault.org/[OpenMediaVault], which is based on
Debian.

To use this backend, you need to install the
http://www.open-iscsi.org/[Open-iSCSI] (`open-iscsi`) package. This is a
standard Debian package, but it is not installed by default to save
resources.

  # apt-get install open-iscsi

Low-level iscsi management task can be done using the `iscsiadm` tool.


Configuration
~~~~~~~~~~~~~

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

portal::

iSCSI portal (IP or DNS name with optional port).

target::

iSCSI target.


.Configuration Example (`/etc/pve/storage.cfg`)
----
iscsi: mynas
     portal 10.10.10.1
     target iqn.2006-01.openfiler.com:tsn.dcb5aaaddd
     content none
----

TIP: If you want to use LVM on top of iSCSI, it make sense to set
`content none`. That way it is not possible to create VMs using iSCSI
LUNs directly.


File naming conventions
~~~~~~~~~~~~~~~~~~~~~~~

The iSCSI protocol does not define an interface to allocate or delete
data. Instead, that needs to be done on the target side and is vendor
specific. The target simply exports them as numbered LUNs. So {pve}
iSCSI volume names just encodes some information about the LUN as seen
by the linux kernel.


Storage Features
~~~~~~~~~~~~~~~~

iSCSI is a block level type storage, and provides no management
interface.  So it is usually best to export one big LUN, and setup LVM
on top of that LUN. You can then use the LVM plugin to manage the
storage on that iSCSI LUN.

.Storage features for backend `iscsi`
[width="100%",cols="m,m,3*d",options="header"]
|==============================================================================
|Content types  |Image formats  |Shared |Snapshots |Clones
|images none    |raw            |yes    |no        |no
|==============================================================================


Examples
~~~~~~~~

Scan a remote iSCSI portal, and returns a list of possible targets:

 pvesm scan iscsi <HOST[:PORT]>

ifdef::wiki[]

See Also
~~~~~~~~

* link:/wiki/Storage[Storage]

endif::wiki[]