My own notes on the Linux iSCSI initiator – applicable to myself, but maybe also to you.

Discover IQNs from the portal

iscsiadm -m discovery -t st -p 192.168.0.x

Log into an IQN (attach it as a drive)

iscsiadm -m node --targetname "iqn.2002-02.com.xsadf:asdfasdf:freenas2:paulextent1" --portal 192.168.0.x --login

Do your thing

Log out of the IQN (make the device go away, from the OS standpoint)

iscsiadm -m node --targetname "iqn.2002-02.com.xsadf:asdfasdf:freenas2:paulextent1" --portal 192.168.0.x --logout

https://wiki.debian.org/SAN/iSCSI/open-iscsi  <– Debian's docs on this