Understanding the iscsiadm Utility: Discover, Log In and Manage iSCSI Disks

Updated: 28 September 2026 · Applies to: iscsi-initiator-utils 6.2.1 on AlmaLinux and Rocky Linux 9 and 10 and RHEL 9 and 10; open-iscsi 2.1 on Ubuntu 24.04 and 26.04 and Debian 13

iscsiadm is the command that connects a Linux server (the iSCSI initiator) to disks offered by a storage server (the target) over the network. It works in modes, chosen with -m: discovery finds targets, node manages the saved target records, and session shows and controls active connections. This guide walks through the normal life cycle of an iSCSI disk.

Before you start

dnf install iscsi-initiator-utils     # AlmaLinux, Rocky Linux, RHEL
apt install open-iscsi                # Ubuntu, Debian
cat /etc/iscsi/initiatorname.iscsi

The last command shows this server's initiator name (IQN). The storage administrator needs it to allow your server access to the LUN.

1. Discover the targets on a storage server

iscsiadm -m discovery -t sendtargets -p 10.0.0.50

This lists the targets the storage server offers to you, as portal,tag IQN, and saves them as node records.

2. Log in

iscsiadm -m node -T iqn.2026-09.com.example:storage.lun1 -p 10.0.0.50 -l

After the login, the LUN appears as a new disk (check with lsblk). Use iscsiadm -m node -l to log in to all saved targets.

3. Log in automatically at boot

iscsiadm -m node -T iqn.2026-09.com.example:storage.lun1 -p 10.0.0.50 -o update -n node.startup -v automatic
systemctl enable iscsid

In /etc/fstab, add _netdev,nofail to file systems on iSCSI disks, so the system waits for the network and still boots if the storage is unreachable.

4. See what is connected

iscsiadm -m session            # active sessions
iscsiadm -m session -P 3       # details, including which disk (sdX) belongs to each session
iscsiadm -m node               # saved target records

5. Authentication (CHAP)

If the target requires CHAP, set the user name and password on the node record before logging in:

iscsiadm -m node -T IQN -p 10.0.0.50 -o update -n node.session.auth.authmethod -v CHAP
iscsiadm -m node -T IQN -p 10.0.0.50 -o update -n node.session.auth.username -v myuser
iscsiadm -m node -T IQN -p 10.0.0.50 -o update -n node.session.auth.password -v 'mysecret'

6. Rescan, log out and remove

iscsiadm -m session --rescan                                  # find new or resized LUNs
iscsiadm -m node -T IQN -p 10.0.0.50 -u                       # log out
iscsiadm -m node -T IQN -p 10.0.0.50 -o delete                # forget the target

Stop using the disk before you log out; the full procedure is in how to delete an iSCSI target on the initiator. With several network paths to the same LUN, combine the sessions with multipath; see how to scan for new LUNs with multipath.

Common problems

• "iscsiadm: No portals found": the target does not allow your initiator name, or a firewall blocks TCP port 3260.
• "Login failed ... authorization failure": wrong CHAP details, or the IQN is not allowed on the storage side.

Official documentation: Configuring an iSCSI initiator (Red Hat) and open-iscsi.