After adding a redundant path to the S-VOL of a GAD pair from a server, set the asymmetric access status of the host group.
In a cross-path configuration, if the ALUA mode is enabled for the first time, all paths including cross paths between a server and a storage system are set as the preferred path. Therefore, you need to set the asymmetric access status of the cross path as a nonpreferred path. By doing so, paths between the server and the storage system in the primary site and between the server and the storage system in the secondary site can be preferably used.
- It is not necessary to set the asymmetric access status if the cross-path configuration is not used.
- If a volume connected to a host via NVMe-oF is used as a GAD pair volume, the asymmetric access status setting is not required. (The ALUA equivalent function in the NVMe-oF host interface is not supported.)
- Before setting the asymmetric access status, enable the ALUA mode. See Setting the ALUA mode.
Command example
raidcom modify lun -port CL1-A-0 -lun_id all -asymmetric_access_state non_optimized -IH0
Check command and output example
Check if the asymmetric access status is set correctly, and then make sure that the ALUA mode (AL) is enabled (E) and that the asymmetric access status (AAS) of the cross path is set to nonpreferred (AN).
raidcom get lun -port CL1-A-0 -key opt_page1 -fx -IH0 PORT GID HMD LUN NUM LDEV CM Serial# AL AAS CL1-A 0 LINUX/IRIX 0 1 2222 - 822222 E AN