ISCSI configuration is a very tricky topic of the RHCE 7 exam.
If a RHCE candidate takes the exam without previous iScsi experience, he will fail!
Man pages are not enough to understand the intricacy of this subject and there is too much to read in a so limited time.
With iScsi configuration, you have to choose among several backstores, mainly fileio and block. Then, you have to set authentication, basic or CHAP (Challenge Handshake Authentication Protocol).
Also, you have to understand what is a target (the server side), an initiator (the client side), a LUN (Logical Unit Number), a portal (an entry point consisting of an ip address and a port), a TPG (Target Portal Group) and an ACL (Access Control List).
To get comfortable with this topic, you will have to practice iSCSI configuration at least 8 times: with each kind of backstores, with each kind of main authentication mechanisms and at least twice to get it memorized!