Dell EMC Unity: How to identify the Primary Storage Processor (User Correctable)


   Article Number:     540082                                   Article Version: 3     Article Type:    How To 




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The management software (ECOM) handles Unisphere, the management interface, and other services. This process runs on one SP at a time (primary).   
    The SP that is currently running the management software is designated as the Primary SP in the Service page in Unisphere, as shown in Figure below   
    User-added image   
    It is also possible to identify the Primary Storage Processor over ssh or Serial Over LAN (SOL) connection. The primary SP will return a PID (Process ID) for ECOM:   
    spa:~/user# pgrep ECOM     
    The non-Primary SP does not run the ECOM service and  command will not display any PID.   
    For guidance on how to use the IPMItool for SoL connections, please refer to the ipmitool technical notes doc available from the support pages.






Unlike the legacy Dell EMC VNX and CLARiiON arrays where the management process (Management Server) was active on both Storage Processors, on Unity arrays, the choice was made to have only one active Storage Processor  (Primary SP) to reduce the number of IP addresses required.   
    If the primary SP reboots, panics, or the management connection goes down, the management software automatically fails over to the peer SP. After a failover, it may take a few minutes for all of the services to fully start. Users that are logged in to Unisphere during the failover may see a message indicating that the connection has been lost. When the failover process completes, you can restore access to Unisphere by refreshing the browser.   
    Note that host access to storage data resources is not affected by this.   
    After the failover, the management software continues to run on the new SP, even if the other SP returns to a healthy state. This SP continues to run as the Primary SP, until it is rebooted or failed over.