- Windows Hyper-V Server 2012
- Windows Hyper-V Server 2012 R2
- Windows Server 2012
About 3 weeks ago, I completed the physical hardware installation of redundant NIC’s in a Hyper-V cluster that was backed onto a Windows Server 2012 server iSCSI SAN. The additional physical NIC’s were installed on the clients and communication between nodes worked as expected. The ports on the new NIC were placed into a new private address range of 192.168.100. Some were also removed from an existing multi-port NIC in the 192.168.254/24 range.
A couple of weeks later it came time to change the iSCSI SAN targets on the clients to use a the new adapters to move from 254/24 to 100/24.
With the correct firewall and chap settings, it should have connected. Instead it returned
The firewall’s were OK, ping was OK. The DNS Connection Suffix, DNS Server (or lack of) were OK and NetBIOS over TCP/IP was disabled.
I could remove and reconnect the server using the original address without any problems.
Without wishing to be verbose on this one, the simple answer is that it appears to be a bug / limitation / “feature” of the iSCSI Target component of Server 2012. It was not a client issue.
The problem was that Windows had not been rebooted since standing up the new multi-port NIC (some 3 weeks prior). Yes, it was rebooted to put the hardware in, but once the NIC heads on the adapter had been configured it had not been rebooted subsequently.
It would appear that Storage Manager in Server 2012 does not force the iSCSI Target driver subsystem to re-parse the available adapter list.
In going into Server Manager > File and Storage Services > (right click the Storage server offering the iSCSI LUN) > iSCSI Target Settings
The list contained a number of network addresses that were REMOVED 3 weeks ago, but none of the NEW IPv4 or IPv6 addresses assigned to the new NIC were available.
Closing and re-opening Storage Manager made no difference.
I sighed and being forced into unexpected maintenance on the cluster storage back end shutdown the cluster, updated drivers and firmware, cleared out Windows Update and rebooted.
After the reboot, all of the new addresses were available in Storage Manager and the redundant ones had disappeared.
So quite simply, reboot (or fully restart all iSCSI services).