Here we are with one of the last steps to configure the iSCSI targets on a NAS4Free Server. In order to complete this part of the setup we need enable the iSCSI service and configure the settings pertinent to the iSCSI targets like a Portal, the Extents and optionally the Authentication we want to enforce for the iSCSI initiators to connect.
From the Services > iSCSI Targets page let’s start enabling the iSCSI service. This will automatically generate the Base Name which essentially is the IQN name to identify the Target. We can leave the rest of the options as default for now. We might need to change the security model later should we need to challenge which iSCSI initiators are allowed to connect and to which extent
Once the service is enabled let’s take a look at the creation of a Portal. This one is responsible for presenting all the available Targets associated. Of course it is possible to have multiple Targets “listening” on different ports. By default iSCSI uses TCP 3260. So let’s make firewall rules are configure to allow this traffic inbound to NAS4Free Server from the clients. Another recommendation I would share in this case is to avoid routing iSCSI traffic from different subnets. Both iSCSI targets and initiator should be in the same network or domain broadcast. When creating a new portal NAS4Free will automatically default to the configured network interface. So it would be just a matter of accepting the default configuration and hit on “Apply for changes”. Another scenario could be instead to route the traffic on a separate network interface using a different IP address. This way the Management traffic will be isolated from the iSCSI or Data traffic
Next is to configure the iSCSI initiators. By default NAS4Free has the option to accept connections from ALL initiators. Of course it is possible to limit this to specific networks and even individual IP Addresses. On top of this we can also challenge the “allowed” initiators with a username and password by mean of CHAP options in the Authorization tab. Usually this is an extra step to be completed after making sure all the connections are working as expected
At this point we are ready to create iSCSI Targets. These Targets are essentially the “friendly names” for the Extents. So from the Targets tab let’s hit on the “plus” button adding our first extent for the Quorum disk
In my case I’m creating the Extent for the Quorum disk. Please be aware not to put any white space in the name otherwise the iSCSI service will fail to load. Let’s specify the “File” option where this would be created (in this case the Pool for Quorum) and the approximate size. In theory we could have chosen the “Auto” size but looks like there is a bug with this configuration leaving us determining approximately the size of that file on the disk
So let’s repeat the same steps also for the remaining extents and we should get something similar to this one
Once ready let’s click on the Target “+” button and at this point we can create the iSCSI Target for the Quorum disk. Again refrain from using white spaces in the name. As a type select “Disk” with Read/Write flag
Let’s repeat the steps for the remaining 4 drives and we’ll get to the configuration below
In the meantime we can also take a quick look at the tail of the log just to make sure everything is working as expected from the Diagnostic > Log page
Everything looks great! So it’s time to test this with a Windows Server connecting to these Targets. All we have to do is to run the built-in iSCSI client in Windows Server (Windows Server 2008 and older requires a separate download) and specify either the address of our NAS4Free server or its IP Address. Personally I like Hostnames making sure DNS name resolution is working as expected
As soon as we hit on “OK” by going to the Targets tab we can see the list of available targets we can connect to
should this fail make sure connectivity between the Server and Client is operational and a quick test would be run a telnet to NAS4free host on port 3260 to check port is open and reachable. So something like:
telnet NAS4FreeName or IPAddress 3260
If it turns a blank command prompt then is good news as port is open and reachable. In a different case I would recommend to check firewall and connectivity settings again between the NAS4Free server and the clients.
This pretty much concludes this article. Next one will cover how to mount the iSCSI Targets on SQL Failover Cluster
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