The iscsiadm utility is a powerful command-line tool used for administering the iSCSI initiator on Linux systems. It allows users to manage iSCSI discovery, node configuration, and session management, which are crucial for connecting to and utilizing iSCSI storage arrays.

Discover iSCSI Targets

Before logging into an iSCSI target, you need to discover available targets on a specific iSCSI portal. This command scans the specified IP address and port for discoverable iSCSI targets.

# Discover targets at iscsi portal ADDR:PORT
# Prints a list of available iscsi targets, example:
#
# <target-ip>:<port>  <IQN>
# 10.10.10.42:3260,1 iqn.2007-10:iscsi.target0
iscsiadm -m discovery -t sendtargets -p ADDR:PORT

Log In to an iSCSI Target

Once targets are discovered, you can log in to a specific iSCSI target using its Qualified Name (IQN) and portal address. This establishes a connection to the storage resource.

# login to target IQN at portal ADDR:PORT:
iscsiadm -m node -T IQN -p ADDR:PORT --login

Log Out from an iSCSI Target

To disconnect from an iSCSI target, you can use the logout command. This releases the connection to the specified target.

# logout from specified target IQN:
iscsiadm -m node -T IQN --logout

List Active iSCSI Sessions

This command displays all currently active iSCSI sessions, showing which targets are connected and their status.

# list active sessions:
iscsiadm -m session

Log Out from All Active Sessions

For a comprehensive disconnection, you can log out from all active iSCSI sessions simultaneously.

# logout from all active sessions:
iscsiadm -m node --logout

Further Reading

• iscsiadm man page
• Open-iSCSI Project Wiki
• RFC 7159 - Internet Standard for iSCSI