clusteringsql server
I am a SharePoint architect but looking to implement AOAG with SharePoint in an Azure lab environment.
I'm building the first node in a cluster and I'm a little confused:
I have my cluster object in AD, the installation asks me for a network name for SQL Server. What's the difference between this and the cluster object name?
Likewise, also the cluster resource group name.
Lastly, what's the IP address specified for?
Without looking at the cluster logs or any other form of error reporting, all I can do is guess here.
But my initial thoughts are that you may have hit the failover threshold. By default, this is going to be set to a maximum of n - 1 failures (where n is the number of nodes) over a period of 6 hours. Yes, that's a long time, and especially in a 2-node cluster that isn't very many failures (only equates to one failure). This threshold is set to prevent the Ping-Pong effect of cluster groups.
In production, this is probably a good thing. But in testing/development/non-prod it is pretty common to run into this initially perplexing problem, as you may be trying to consecutively failover. It is worth noting that these parameters are 100% configurable. All you need to do is go into the properties of the cluster group, and in the "failover" tab you will have the option to change these two parameters (Maximum failures in the specified period and Period (hours). Here is what this looks like in the Failover Cluster Manager:
Note: in my screenshot, the threshold is set to 2 because I have a 3-node cluster.
Likewise, this can be seen with PowerShell (accessing the FailoverClusters module).
# you may need to set your cluster group name to whatever it is named
# in your environment
#
Get-ClusterGroup -Name "SQL Server (MSSQLSERVER)" |
Select-Object Name, FailoverThreshold, FailoverPeriod
Given CLUSTER_1, with NODE_1 and NODE_2, and virtual network VNN_1 with IP_1, these will work:
These will not work:
If you are unable to connect using VNN_1\INSTANCE then, can you ping it, and what does it resolve to? Is it configured for a single IP (i.e. not multi-subnet)?
Best Answer
The network name is a virtual client access point for the instance of SQL Server on the failover cluster, and it needs to be unique on the domain. This will be how you will connect to the instance.
The Cluster resource group is the name by which everything is grouped in the Windows Failover Cluster Manager, you will typically want this named similarly to what you named the instance.
The IP you provide will be tied to the network name you provided and needs to be unique as well.