Cannot attach iSCSI if session exists with portal as FQDN

Cinder and OS-Brick use static IP addressing for iSCSI portals, and this will work as expected when OS-Brick is the only managing the iSCSI sessions.

On drivers that share the targets we will have problems if we manually set the target/portal before Cinder/Nova have attached a volume and we use the FQDN for the portal instead of an static IP.

The problem is that the iSCSI initiator will reuse the session it already has but OS-Brick will not be able to find the session, because the FQDN does not match the static IP Portal we are trying to use.

What is even worse is that it ends up in an endless loop because it knows that it has been able to login and that the session must be there, so it keeps trying to find it.