Storage: iSCSI

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. OpenMediaVault, which is based on Debian.

To use this backend, you need to install the 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

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 Proxmox VE 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.

Table 1. Storage features for backend iscsi

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]>

See Also

• Storage