Iscsi

Configure Storage Server with iSCSI.

Storage server with iSCSI on network is called iSCSI Target.
Client Host that connects to iSCSI Target is called iSCSI Initiator.

Install target

dnf -y install scsi-target-utils

Create a disk image

mkdir /ssd/iscsi
dd if=/dev/zero of=/ssd/iscsi/target001.img count=0 bs=1 seek=10G
vim /etc/tgt/conf.d/target01.conf
<target iqn.2022-03.se.halfface.iscsi:target001>
    # provided devicce as a iSCSI target
    backing-store /ssd/iscsi/target001.img
    # iSCSI Initiator's IQN you allow to connect. Or set nothing to allow all.
    initiator-name iqn.2022-03.se.halfface.iscsi:node01.initiator01
#    initiator-address 10.111.222.13
    # authentication info ( set anyone you like for "username", "password" )
    incominguser username password
</target> 

If selinux.

chcon -R -t tgtd_var_lib_t /ssd/iscsi
semanage fcontext -a -t tgtd_var_lib_t /ssd/iscsi

Open firewall

firewall-cmd --add-service=iscsi-target --permanent
firewall-cmd --reload

Start tgtd

systemctl enable --now tgtd

show status

tgtadm --mode target --op show

Install initiator

dnf -y install iscsi-initiator-utils
vim /etc/iscsi/initiatorname.iscsi
InitiatorName=iqn.2022-03.se.halfface.iscsi:node01.initiator01
vim /etc/iscsi/iscsid.conf
node.session.auth.authmethod = CHAP
node.session.auth.username = username
node.session.auth.password = password

Start iscsid service.

systemctl enable iscsid.service
systemctl restart iscsid.service

Discover target

iscsiadm -m discovery -t sendtargets -p 10.111.222.1
[ 1542.659413] Loading iSCSI transport class v2.0-870.
[ 1542.679005] iscsi: registered transport (tcp)
10.0.0.30:3260,1 iqn.2019-11.world.srv:dlp.target01

Confirm status after discovery

[root@node01 ~]# iscsiadm -m node -o show
# BEGIN RECORD 2.0-876
node.name = iqn.2019-11.world.srv:dlp.target01
node.tpgt = 1
node.startup = automatic
node.leading_login = No
iface.iscsi_ifacename = default
...
node.conn[0].iscsi.IFMarker = No
node.conn[0].iscsi.OFMarker = No
# END RECORD

Login to the target

iscsiadm -m node --login
Logging in to [iface: default, target: iqn.2019-11.world.srv:dlp.target01, portal: 10.0.0.30,3260] (multiple)
Login to [iface: default, target: iqn.2019-11.world.srv:dlp.target01, portal: 10.0.0.30,3260] successful.

Confirm the established session

iscsiadm -m session -o show
tcp: [1] 10.0.0.30:3260,1 iqn.2019-11.world.srv:dlp.target01 (non-flash)

Confirm the partitions

lsblk

Format and mount disk

gdisk /dev/sda
mount /dev/sda1 /mnt/

1. logout from all sessions.

iscsiadm -m node -u