HDLM functions, such as load balancing and failover, are only available for HDLM management-target devices that have more than one active path. After you install HDLM or change the hardware configuration, check the structure and statuses of the paths.
To check the path information, use the dlnkmgr command's view operation.
The following describes how to check path information by using the dlnkmgr command's view operation. For details about the view operation, see view (displays information).
- Specify the -path parameter and check the output information:
Execute the following command:
# /opt/DynamicLinkManager/bin/dlnkmgr view -path > redirect-destination-file-1
Open redirect-destination-file-1 and check the following:
Make sure that there is at least one LU being accessed by a path.
A path can be identified by PathName. The LU that is accessed by a path can be identified by both DskName and iLU.
Make sure that all the paths are online.
Make sure that PathStatus is Online. If a path is not online, Reduced will be displayed.
Make sure that for each path the combination of the CHA port (ChaPort), through which multiple paths are accessing the same LU, and the HBA port (the host port number and bus number displayed in the PathName column) is different.
The digits displayed on the left of PathName indicate a host port number. The numbers displayed between the period to the right of the host port number and the next period indicate a bus number.
Make sure that there are different host port numbers and bus numbers for each physical HBA port.
- Specify the -drv parameter and check the output information:
Execute the following command:
# /opt/DynamicLinkManager/bin/dlnkmgr view -drv > redirect-destination-file-2
Open redirect-destination-file-2 and check the HDevName and Device entries to see whether the HDLM device corresponding to the SCSI device has been created.