IP partnership configuration

Configuring an IP partnership with a remote system requires that you follow a specific set of steps.

To configure an IP partnership with a remote system, follow these steps:

Determine whether you have met all partnership requirements, as described in IP partnership requirements.
For each node port that is to be used in the IP partnership, configure the ports on both systems using the CLI command cfgportip. Configuration includes assigning each port to a remote copy port group, as described in Remote-copy port groups.
Remote copy port groups are unique to IP partnerships and are the local and remote IP addresses accessible to each other through an IP partnership.
You can also use the management GUI to do this task:
1. Select Settings > Network > Ethernet Ports.
2. Right-click the port, and then select Modify.
Configure an IP partnership on the local system by running mkippartnership on that system. Specify the challenge handshake authentication protocol (CHAP) secret, if necessary.
1. The partnership link bandwidth parameter must be less than or equal to the bandwidth of the intersite link.
2. If you want to do background copy, the amount of link used is governed by the background copy rate parameter. Adjust this parameter so there is enough bandwidth available for the largest host I/O burst expected.
  Use the following equation to determine the approximate percentage: background copy rate = ((Intersite link's bandwidth in Mbps - approximate maximum Host I/O in Mbps expected - 0.125 Mbps heartbeat traffic) / Intersite link's bandwidth in Mbps) x 100
Note: To use the management GUI to do this task and also the task in step 4, select Copy Services > Partnerships and then select Create partnership.
Configure an IP partnership on the remote system by running mkippartnership on the remote system, specifying the CHAP secret you provided in step 3.

Figure 1 displays the configuration of an IP partnership.

Figure 1. IP partnership configuration

Optional: Using CHAP with an IP partnership

Data exchange between the local system and partner system over an IP connection can be protected through CHAP, which uses a shared secret to authenticate systems with each other when sending requests.

Note: You can also specify that the same CHAP secret be used to authenticate the system 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, click Modify CHAP Configuration on each system to specify a system-wide CHAP secret. Select Use for IP partnerships. Two paths exist to access this dialog in the management GUI:

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

Before you can create an IP partnership, you must define a CHAP secret locally on both systems. Then you must configure CHAP to be used for IP partnerships on both systems. For example, when creating an IP partnership that uses CHAP between local system A and partner system B, a CHAP secret must have been defined previously on both systems A and B. CHAP secret values on systems A and B can be different. On local system A, specify the partner system B CHAP secret by using Create Partnership or Partnership Properties. On system B, specify the system A CHAP secret by using one of those same options.

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 you can modify the CHAP configuration.