Creating a target: https://www.certdepot.net/rhel7-configure-iscsi-target-initiator-persistently/
1) install targetcli package
# yum install targetcli
# systemctl start target
# systemctl enable target
2) start targetcli: http://linux-iscsi.org/wiki/Targetcli
# targetcli
3) create filebacked target
> backstores/fileio create lun0 /opt/lun0.img 100M

User-backed targetS:
https://github.com/open-iscsi/tcmu-runner

3) create user target
> backstores/user:hello create lun0 100M unneeded
4) set iqn
> iscsi/ create iqn.2009-11.com.kitwestneat:t1
5) export LUN
> cd iscsi/iqn.2009-02.com.ddn:t1/
> tpg1/luns create /backstores/user:hello/lun0
6) create ACL
> tpg1/acls create 2009-11.com.kitwestneat:client
7) on initiator:
# iscsiadm –mode discovery –type sendtargets –portal 192.168.10.3
# iscsiadm –mode node –portal 192.168.10.3 –targetname iqn.2009-11.com.kitwestneat:t1 –login
8) test it
[root@localhost ~]# dd if=/dev/sda bs=100 count=5
Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello world!Hello 5+0 records in

Gluster use case:

Gluster Solution for Non Shared Persistent Storage in Docker Container

Gluster as swift backend
https://github.com/openstack/swiftonfile