Persistently exposing iSCSI LUNS after a reboot

[Neil_Sherin]

Hiya,

I've just set up an Ubuntu 18.04 VM with a second 10GB drive as a test that I want to set up as block storage over iSCSI. The problem is, when I reboot the iSCSI target VM, the LUN dos not show up when running tgtadm --mode target --op show

Running a systemctl restart fixes the issue and the LUN shows up as LUN 1 when running tgtadm --mode target --op show

Here's what I did to set up an iSCSI target:

Assume:

/dev/sdb is the disk to use as an iSCSI LUN
iqn.2019-07.local.nsnetworks:netstorage is the target name
192.168.1.30 is the IP address of the iSCSI target portal

Setting up the target:

• Install required packages:

sudo su -
apt install -y tgt

• Create iSCSI target (tid 1)

tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.2019-07.local.nsnetworks:netstorage

• Add logical Unit (lun 1) to iSCSI target (Target ID 1)

tgtadm --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 -b /dev/sdb

• Publish iSCSI target (tid 1) to all IP address

tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL

• Save configuration for iSCSI target. If you do not save configuration, configuration will be removed after restarting tgtd

tgt-admin --dump |grep -v default-driver > /etc/tgt/conf.d/disk.conf

• Enable service:

systemctl enable tgt

• Show status

tgtadm --mode target --op show

Any help getting the LUN to show up persistently when the iSCSI target is rebooted would be much appreciated!

Many thanks in advance!

[Neil_Sherin]

i then tried to set up a udev mapping to see if that would resolve the issue:

• Create udev rule for proper device mapping of sdX to iscsi_X on boot

Using sdb as an example:

udevadm info --query=property --name=/dev/sdb

Make a note of the values of:
ID_SCSI_SERIAL
ID_SERIAL
ID_SERIAL_SHORT

Create symbolic link for iscsi_1 mapping:

ln -s /dev/sdb /dev/iscsi_1

Set up udev rule:

nano /etc/udev/rules.d/70-persistent-drive.rules

Add the following:

SUBSYSTEM=="block", ENV{ID_SCSI_SERIAL}=="6000c29831ec9a7d45dc007e6439 a6d6", ENV{ID_SERIAL}=="36000c29831ec9a7d45dc007e6439a6d6 ", ENV{ID_SERIAL_SHORT}="6000c29831ec9a7d45dc007e6439 a6d6". SYMLINK+="iscsi_1"

Reload udev rules:

udevadm control --reload-rules && udevadm trigger

On reboot, it still does not expose the LUN. I have to do the following to get the LUN exposed:

ln -s /dev/sdb /dev/iscsi_1
udevadm control --reload-rules && udevadm trigger
systemctl tgt restart

Again, any help would be much appreciated.

[darkod]

Did you go through the official doc in case something there can help you? It seems they are doing it in a different way (hasn't worked with iscsi that much lately myself).
https://help.ubuntu.com/lts/servergu...initiator.html