General Information

iSCSI operations on Linux.

Checklist

• Enterprise Linux 6/7

Red Hat's recommended procedure for removing storage devices.

1. Ensure all files open on the device are closed

   lsof | grep <devname>

2. Backup/move data as needed
3. Remove device from any software RAID or LVM volume
4. Remove device from multipath
5. Flush outstanding I/O (important for raw devices)

   blockdev --flushbufs <device>

6. Remove references to the device from applications, scripts, etc.
7. Remove each path to the device from the SCSI subsystem

   echo 1 > /sys/block/<device-name>/device/delete

   1. Where <device-name> can be something like 'sde'

Example iscsiadm commands.

View iscsi target node IP addresses and target names

iscsiadm --mode node

Enable iscsi target: Login to iscsi target

iscsiadm --mode node --targetname <iscsi-target-name> --portal 192.168.1.100:3260 --login

Disable iscsi target: Logout from iscsi target

iscsiadm --mode node --targetname <iscsi-target-name> --portal 192.168.1.100:3260 --logout

Delete iscsi target

iscsiadm --mode node -o delete --targetname <iscsi-target-name> --portal 192.168.1.100:3260

If the iSCSI device that is removed is also multipath'd, remove it from multipath configuration also.

View multipath devices

multipath -ll

Remove (flush) an unused multipath device

multipath -F

After, restart multipathd to ensure it doesn't come back

• EL6

  service multipathd restart

• EL7

  systemctl restart multipathd