Unisphere: Why Using for VMAX and Solutions Enabler Simultaneously is Not Advised

It is a Dell best practice to use either Unisphere for VMAX or Solutions Enabler (SYMCLI) to manage storage, but not both simultaneously.

Using both simultaneously may result in the Unisphere UI being out of sync with the latest storage environment information.

Take the simple scenario where Unisphere is installed on a SYMAPI server:

• The SYMAPI server keeps an up-to-date database of the storage environment called "symapi_db.bin." This means that not all commands and queries must be sent from the SYMAPI host all the way to the storage array, but instead can query the symapi_db on the host for quicker responses.
• When a configuration change is made on an array through either Unisphere or SYMCLI, the checksum value on the array is updated. The event daemon on the SYMAPI server "storeventd" monitors the array for these checksum changes, and when it occurs, the event daemon prompts the base daemon, "storapid" to run a "symcfg discover." This updates the symapi_db with the latest storage environment information, so that the symapi_db is always up to date.
• However, the Unisphere software has no knowledge of the event daemon, or array checksum. Unisphere relies instead on its own Object Model (cache), which is built from the symapi_db. However, it is an intensive operation to build this Object Model and for this reason it is only rebuilt from the symapi_db when the SMAS server is starting up. That is, to rebuild the Unisphere Object Model, a restart the SMAS service is required.
• When changes are made through Unisphere, the UI sends the required command to Solutions Enabler where it runs as if it were a SYMCLI command, and it also notes the configuration in the Object Model. What this means is that the Unisphere Object Model will always be aware of configuration changes made through the UI itself, but it has no knowledge of any changes made using SYMCLI.

For this reason, and to avoid having to restart the SMAS service regularly, it is a Dell best practice to use either Unisphere for VMAX or Solutions Enabler (SYMCLI), but not both simultaneously.