If the sysadmin password is lost or unknown, but you can ssh to the control station and log on as nasadmin, then you can run the following commands to view any additional admin accounts (if any were created).
/nas/sbin/navicli -h spa security -list -type
If there is another admin account on the system, try using the username as the password and see if that works.
If not, then you can create a temporary administrator account using the following command
/nas/sbin/navicli -h spa security -adduser -user tempadmin -password tempadmin -scope 0 -role administrator
This will allow you to log into the Unisphere global scope at the control stations IP address as tempadmin, where you can then reset the sysadmin password on VNX.
After verifying that you can now log back in to Unisphere as sysadmin, don’t forget to delete the tempadmin account from Settings, Global Users in Unisphere.
Official emc video available here https://community.emc.com/videos/5642