You download the latest SANtricity OS software file from the Support site (a link is available from Unified Manager in the Support page). Save the file on the management host system (the host where you access Unified Manager in a browser), and then unzip the file.
In Unified Manager, you load the SANtricity OS software file and the NVSRAM file into the repository (an area of the Web Services Proxy server where files are stored). You can add files either from Upgrade Center > Upgrade SANtricity OS Software or from Upgrade Center > Manage Software Repository.
After the files are loaded in the repository, you can then select the file to be used in the upgrade. From the Upgrade SANtricity OS software page (Upgrade Center > Upgrade SANtricity OS software), you select the SANtricity OS software file and the NVSRAM file. After you select a software file, a list of compatible storage systems appear on this page. You then select the storage systems that you want to upgrade with the new software. (You cannot select incompatible arrays.)
You can then begin an immediate software transfer and activation, or you can choose to stage the files for activation at a later time. During the upgrade process, Unified Manager performs the following tasks:
1. Performs a health check on the storage systems to determine if any conditions exist that might prevent the upgrade from completing. If any arrays fail the health check, you can skip that particular array and continue the upgrade for the others, or you can stop the entire process and troubleshoot the arrays that did not pass.
2. Transfers the upgrade files to each controller.
3. Reboots the controllers and activates the new SANtricity OS software, one controller at a time. During activation, the existing SANtricity OS file is replaced with the new file.
  
  You can also specify that the software is activated at a later time.

Immediate or staged upgrade

You can activate the upgrade immediately or stage it for a later time. You might choose to activate later for these reasons:

Time of day
Activating the software can take a long time, so you might want to wait until I/O loads are lighter. Depending on the I/O load and cache size, a controller upgrade can typically take between 15 to 25 minutes to complete. The controllers reboot and fail over during activation so performance might be lower than usual until the upgrade completes.
Type of package
You might want to test the new software and firmware on one storage system before upgrading the files on other storage systems.

To activate staged software, go to Support > Upgrade Center and click Activate in the area labeled SANtricity OS Controller Software upgrade.

Health check

A health check runs as part of the upgrade process, but you can also run a health check separately before you begin (go to Upgrade Center > Pre-Upgrade Health Check).

The health check assesses all storage system components to make sure that the upgrade can proceed. The following conditions might prevent the upgrade:

Failed assigned drives
Hot spares in use
Incomplete volume groups
Exclusive operations running
Missing volumes
Controller in Non-optimal status
Excess number of event log events
Configuration database validation failure
Drives with old versions of DACstore

What do I need to know before upgrading?

Before you upgrade multiple storage systems, review the key considerations as part of your planning.

Current versions

You can view the current SANtricity OS software versions from the Manage page of Unified Manager for each discovered storage system. The version is shown in the SANtricity OS Software column. The controller firmware and NVSRAM information is available in a pop-up dialog box when you click on the SANtricity OS version in each row.

Other components requiring upgrade

As part of the upgrade process, you might also need to upgrade the host’s multipath/failover driver or the HBA driver so that the host can interact with the controllers correctly.

Also, see the procedures in the Express Guides for your operating system. Express Guides are available from the ETERNUS AB/HB Series and SANtricity documentation.

Dual controllers

If a storage system contains two controllers and you have a multipath driver installed, the storage system can continue to process I/O while the upgrade occurs. During the upgrade, the following process occurs:

Controller A fails over all its LUNs to controller B.
Upgrade occurs on controller A.
Controller A takes back its LUNs and all of controller B’s LUNs.
Upgrade occurs on controller B.

After the upgrade completes, you might need to manually redistribute volumes between the controllers to ensure volumes return to the correct owning controller.