Partnerships over native IP connections

In addition to Fibre Channel and Fibre Channel over Ethernet (FCoE) connections, Metro Mirror and Global Mirror partnerships can be established over Ethernet links using the IPv4 and IPv6 addresses associated with Ethernet ports. These IP partnerships can be connections through Ethernet switches, or direct connections between local and partner systems. Partnerships must be created as either an IPv4 or IPv6 partnership.

IP partnerships can also support data compression. Both systems in the IP partnership must be running a software level that supports IP partnership data compression. A compression accelerator must also be installed on each system. For more information, see Configuring IP partnerships.

Using CHAP with an IP partnership (optional)

You can protect data exchange between the local system and partner system over an IP connection through challenge handshake authentication protocol (CHAP), which uses a shared secret to authenticate systems with each other when sending requests.

Note: You can also use a CHAP secret to authenticate with iSCSI-attached hosts. The system-wide CHAP secret is used for all CHAP authentication from the local system to partner systems and to iSCSI-attached hosts.

To configure CHAP for IP partnership, use the Modify CHAP Configuration dialog on each system to specify a system-wide CHAP secret, and select Use for IP partnerships. Two paths exist to this dialog in the management GUI:

Select Copy Services > Partnerships, then select Actions > Modify CHAP Configuration.
Select Settings > Network > iSCSI > Modify CHAP configuration.

Before creating an IP partnership, define a CHAP secret for each system, then configure CHAP to be used for IP partnerships on each system.

For example, when creating an IP partnership that uses CHAP between system A and system B, first define a CHAP secret on each system. The CHAP secret value on systems A and B can differ. On system A, specify the system B CHAP secret in the Create Partnership or Partnership Properties dialog, then on system B, specify the system A CHAP secret using one of the dialogs.

When creating an IP partnership on a local system using CHAP, if you do not specify the system-wide CHAP secret of the partner system, the local system displays a CHAP authentication failure message. If an IP partnership using CHAP is active, you must stop the partnership before modifying the CHAP configuration.