Troubleshooting file system issues

4 hours
  • 3 Learning Objectives

About this Hands-on Lab

**Warning**: This lab represents a significantly broken environment and goes well beyond simple troubleshooting.

In this lab, you must resolve any issues preventing the content mounted at `/storage` from being accessed.

Learning Objectives

Successfully complete this lab by achieving the following learning objectives:

Verify the iSCSI target configuration and status.

On Server1 (

Verify the target service is running:

systemctl status target

Start and enable the target service:

systemctl start target && systemctl enable target

Verify the process is listening on port 3260:

ss -ltnp | grep 3260

Check if the firewall is permitting traffic over 3260/tcp:

firewall-cmd --list-all

Permit incoming traffic over port 3260/tcp:

firewall-cmd --permanent --add-port=3260/tcp

Reload the firewall:

firewall-cmd --reload

View the iSCSI target configuration:

/> ls
Verify the iSCSI initiator configuration and status.

On Server2 (

View any existing node entires:

iscsiadm -m node

Verify the initiator name matches the ACL from the target:

cat /etc/iscsi/initiatorname.iscsi

Change the name to match the target:

Verify security settings match those of target:

less /etc/iscsi/iscsid.conf
#node.session.auth.authmethod = CHAP
#node.session.auth.username = username
#node.session.auth.password = password

Restart the iscsid service to pick up the change:

systemctl restart iscsid

Discover iSCSI targets from

iscsiadm -m discovery -t sendtargets -p

Log in to target:

iscsiadm -m node -T -l

Enable the iscsid service to permit connection upon reboot:

systemctl enable iscsid
Resolve disk encryption.

Review the contents of /etc/crypttab and /etc/fstab:

cat /etc/crypttab
cat /etc/fstab

Attempt to manually open the volume using the key referenced in /etc/crypttab:

cryptsetup luksOpen /dev/mapper/vg_1-lv_1 luks-vg_1-lv_1 --key-file /root/passphrase.key

View the volume key slots:

cryptsetup luksDump /dev/mapper/vg_1-lv_1

Restore the LUKS header:

cryptsetup luksHeaderRestore /dev/mapper/vg_1-lv_1 --header-backup-file /root/vg_1-lv_1.header

Open the volume manually:

cryptsetup luksOpen /dev/mapper/vg_1-lv_1 luks-vg_1-lv_1 --key-file /root/passphrase.key

View the entries in /dev/mapper:

ll /dev/mapper

Attempt to mount /storage:

mount /storage

View the file system label:


The volume appears to be a swap format, however the entry in /etc/fstab suggests it’s an XFS file system. Repair the file system:

xfs_repair /dev/mapper/luks-vg_1-lv_1

Mount /storage:

mount /storage

View the contents of /storage:

ll /storage

Additional Resources

Resolve any and all issues preventing access to the contents mounted at /storage.

  • is an iSCSI target for the volume mounted at /storage

  • is the iSCSI initiator

  • A backup of the LUKS header is available at /root/vg_1-lv_1.header

Do not format any volumes, do not modify /etc/fstab or /etc/crypttab

The integrity of the existing encryption, filesystems, and files located on the iSCSI volume must be preserved.

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