My QNAP TS-412 had a major issue, 2 of the RAID5 disks decided to fail at the same time. Luckily QNAP was still up and running and allow READ-ONLY access to my data. However, all the iSCSI LUNs are not accessible anymore from my iSCSI clients.

Found the attached document which basically helped me recover my iSCSI LUNs. I copied by iSCSI LUN files to the backup locations and rebuild by NAS volumes. I then follow the procedure #3 in the document to get my iSCSI LUNs back.

Setting Up Hyper-V 2012 R2 Server Core

In the past year or two, I used to have 2 Hyper-V Servers. They are good for hypervisor platform. The best thing I like about having 2 Hyper-V Servers is Replication. I need the replication to make sure my critical virtual machines are available when one of the hosts failed.

Anyway, I decided to shutdown one of the hosts. I still need the replication for my critical virtual machines. My physical host has got a local RAID controller, on which all the virtual machines are running. I decided to create a virtual Hyper-V Server 2012 R2 Core running on this physical host.

Within the virtual Hyper-V server, I initiate iSCSI to my QNAP NAS and set the Hyper-V replication settings to use this iSCSI disk as the target for Hyper-V replication, e.g. all replicated vdisk will be stored in the iSCSI disk

The challenge is to configure Hyper-V server core, which by default has the firewall enabled.
Firstly, I need to enable the firewall for Remote Disk Management. The rules are there, but by default is disabled. We need to find the group on which the rules are specified.

To find the grouping:

Get-NetFirewallRule | Select DisplayGroup -Unique | Sort DisplayGroup

As you can see there is a group called Remote Service Management and Remote Volume Management

 To find the rule within the group:

Get-NetFirewallRule | Where {$_.DisplayGroup -eq "Remote Service Management"} | Select Name

As you can see there are 3 rules associated with the group. To enable them:

Get-NetFirewallRule | Where {$_.DisplayGroup -eq "Remote Service Management"} | Enable-NetFirewallRule

You then need to do the same thing for Remote Volume Management and Hyper-V Replica HTTP

Once you have enabled all the rules, from your physical host, using Server Manager, you can add your Hyper-V Core Server and right click on the server and run Computer Management from the context menu

Now because I would like to run iSCSI initiator from this virtual Hyper-V Core server, I then enable the Microsoft iSCSI Initiator Service and change its startup type to be Automatic

You then need to setup the iSCSI, by running iscsicpl from the command prompt of the Hyper-V Core Server

Enter the details of your iSCSI target and then using the Disk Management you can format and assign a drive letter to the newly created iSCSI disk. Once you have the disk, using Hyper-V Manager, run Hyper-V Settings

Within Hyper-V Settings, select Replication Configuration

Select Enable this computer as a Replica Server, and select either Use Kerberos (HTTP) or Use certificate-based Authentication (HTTPS)

Lastly, specify the default location to store Replica files

You can now start replicating your Virtual Machines!!