Dell PowerVault ME4 Series Storage System Administrator’s Guide

CHAP and replication

If you want to use Challenge Handshake Authentication Protocol (CHAP) for the iSCSI connection between peer systems, see the procedure below to set up CHAP. Make sure that you configure both systems in this way. In a peer connection, both systems will alternately act as an originator (initiator) and recipient (target) of a login request. Peer connections support one-way CHAP only.

If only one system has CHAP enabled and the two systems do not have CHAP records for each other, or the CHAP records have different secrets, the system with CHAP enabled will be able to modify the peer connection. However, it will be unable to perform any other replication operations, such as creating replication sets, initiating replications, or suspending replication operations. The system that does not have CHAP enabled will be unable to perform any replication operations, including modifying and deleting the peer connection. For full replication functionality for both systems, set up CHAP for a peer connection (see the following procedure).

If the two systems have CHAP records for each other with the same secret, they can perform all replication operations whether or not CHAP is enabled on either system. In other words, even if CHAP is enabled on neither system, only one system, or both systems, either system can work with peer connections, replication sets, and replications.

If you want to use Challenge Handshake Authentication Protocol (CHAP) for the iSCSI connection between peer systems, see the following procedure to set up CHAP. In a peer connection, both systems will alternately act as an initiator and target of a login request. Peer connections support one-way CHAP only.