If you use EMC PowerPath, the process is straightforward from EMC. But in most cases, due to the price of EMC PowerPath, we use Microsoft MPIO instead (Which PowerPath uses under the covers)
If using Microsoft’s MPIO, you can use their mpclaim utility from a command line or their GUI for doing all the setup. The following assumes you are using Microsoft MPIO and an EMC VNX storage array. There are only slight variations for other combinations.
- Configure hardware for MPIO.
- Install Microsoft MPIO.
- From a command prompt, issue the command “mpclaim -h” to see the currect storage devices claimed by MS MPIO. With a VNX you should see something like “Vendor 8Product 16″. Looking at the MPIO Devices tab in the GUI will show the same information.
- From a command prompt, issue the command “mpclaim -s -d” and you should see that there are no disk present yet, as you haven’t allowed any.
- From a command prompt, issue the command “mpclaim -e” to display the vendor product ID string for the connected storage array. Depending on how your VNX is configured, you will see something like this “DGC VRAID”. There are exactly five (5) spaces after “DGC” and you must have exactly five spaces in the ID.
- Now you can add the multipath support for the speicifc IDs you want. Obviously you will want whatever you saw in the previous step, but in case you plan on using some other configurations, you can add everything from the list from above. From a command prompt enter the command “mpclaim -n -i -d “DGC VRAID”. The “-n” switch suppresses the automatic reboot. Repeat that commnd for each all device IDs desired.
- Reboot the system.
- From a command prompt, issue the command “mpclaim -s -d” and you should see the disks claimed by MPIO on the node. Again, you can use the GUI for all this, too.
- Run Disk Management and activate the new disk