Configure ASM Storage on RHEL 8.10 over iSCSI on a 2 Node Cluster
A detailed guide to create an iSCSI target server on RHEL 8.10 with 3 drives, and share them with two nodes (initiators). The iSCSI targets will be automatically available after reboot.
✅ Scenario
- OS: RHEL 8.10 (iSCSI Target server)
- Disks: 3 block devices (e.g.,
/dev/sda,/dev/sdb,/dev/sdc,/dev/sdd) - iSCSI Initiators: Two nodes (clients) that will connect to the target
- Goal: Export all 3 drives via iSCSI and ensure they're available post-reboot.
🔧 On the iSCSI Target Server
Step 1: Install Required Packages
sudo dnf install -y targetcli
Step 2: Verify the 3 Disks
Ensure the drives are available:
lsblk
# Example expected output:
/dev/sda
/dev/sdb
/dev/sdc
/dev/sdd
Step 3: Configure iSCSI Targets
Launch targetcli:
sudo targetcli
Now run the following commands inside the targetcli shell:
# Create a new backstore for each disk
/backstores/block create disk1 /dev/sda
/backstores/block create disk2 /dev/sdb
/backstores/block create disk3 /dev/sdc
/backstores/block create disk4 /dev/sdd
# Create an iSCSI target
/iscsi create iqn.2025-07.com.homelab:asmtgt1
# Enter into the target and create a TPG
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1 set attribute authentication=0
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/luns create /backstores/block/disk1
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/luns create /backstores/block/disk2
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/luns create /backstores/block/disk3
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/luns create /backstores/block/disk4
# Allow access to initiators (use wildcard or restrict to IPs)
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/acls create iqn.2025-07.com.homelab:node1
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/acls create iqn.2025-07.com.homelab:node2
# Enable listening on default port
/iscsi/iqn.2025-07.com.homelab:asmtgt1/tpg1/portals create 0.0.0.0 3260
# Save and exit
exit
🔁 Enable Services to Start on Boot
sudo systemctl enable target
sudo systemctl start target
The config is stored persistently under /etc/rtslib-fb-target/saveconfig.json.
🔒 (Optional) Firewall Configuration
sudo firewall-cmd --permanent --add-port=3260/tcp
sudo firewall-cmd --reload
🧪 On Each iSCSI Initiator Node (Client)
Step 1: Install the iSCSI initiator tools
sudo dnf install -y iscsi-initiator-utils
Step 2: Set Initiator Name
Edit /etc/iscsi/initiatorname.iscsi on:
- Node 1:
InitiatorName=iqn.2025-07.com.homelab:node1
InitiatorName=iqn.2025-07.com.homelab:node2
Then restart the service:
sudo systemctl restart iscsid
Step 3: Discover and Login to Target
sudo iscsiadm -m discovery -t sendtargets -p <TARGET-IP>
sudo iscsiadm -m node -T iqn.2025-07.com.homelab:asmtgt1 -p <TARGET-IP> --login
Make the login persistent:
sudo iscsiadm -m node -T iqn.2025-07.com.homelab:asmtgt1 -p <TARGET-IP> --op update -n node.startup -v automatic
🔁 Test Persistence
- Reboot the iSCSI server.
- Reboot both initiator nodes.
- Run
lsblkon initiator nodes – you should see/dev/sdXmapped LUNs.