Cannot get MPIO to work in server 2012 with a Dell MD Power Vault?
Not sure this is limited to Server 2012 or the Dell Power Vaults, but I got caught with this issue after following all the proper procedures.
I installed the Windows Multipath Feature in Windows, along with other features and the Hyper-V Role.
I then after reboots and updates, installed the Dell MD Storage Software which included the Dell MPIO Drivers.
I had my networking configured: 4 NICs on this one server for ISCSI, all ISCSI Traffic Isolated on designated VLAN, on 2 DELL Power Connect Switches.
I have 2 Dell PowerEdge Rack Servers one configured correctly all Sessions working correctly, and 3 LUNs showing up as 3 disks in Disk Management.
The other server same configuration, but the 3 LUNs were showing up as 24 disks in Disk Management, obviously because MPIO was not working.
As advised by Dell I reinstall the Dell MD Storage Software and confirmed with them that I had the latest version.
Didn’t help. Clears out all of my iSCSI configuration and did the reinstall again, and still not working.
After searching the web and a few other resources, I knew the problem was because MPIO Drivers were either not installed correctly, or enabled for these ISCSI Connections.
On the good server my Disk Drives Devices in Device Manager looked like:
On the bad (not working) server my Disk Drives Devices in Device Manager looked like:
So obviously, MultiPath was not going to work.
After 2 hours of trying I decided to search for a MultiPath Control Panel in windows and I found:
Which lead me to:
Automatically I knew this was my problem. My good server had way more Dell devices and models listed.
I added my device IDs based on what I found on the good server and it heavily required (asked multiple times) a reboot.
NOTE: the Device ID must be 8 characters and DELL is only 4 characters, so I added 4 spaces after the word DELL.
Rebooted and checked the MPIO Properties panel to make sure it look like what I configured before the reboot:
(The last line was automatically added, but it match the configuration on my other server).
I then check the device managers and I had 3 Multi-Path Disk Devices:
And now only 3 Disks in Disk Management.