If I disconnect DEV-AWEB5
Define "disconnect", if you will. My guess is you kept the box up but took SQL Server down.
I cannot connect to the Group Listener (DevListener), but I can ping it and it will respond to my ping
That's because the listener is just a virtual network name (VNN) within the WSFC cluster resource group for the represented availability group. Your DEV_AWEB5 node still owns the cluster resource group, but it's just the AG cluster resource most likely that is in a failed state. The VNN must still be online (expected behavior). It's simply pointing to whatever node is owning that resource group (in this case, DEV-AWEB5). In fact, if you had PowerShell remoting enabled, and you ran the following:
Invoke-Command -ComputerName "YourListenerName" -ScriptBlock { $env:computername }
Likewise, if you can RDP into DEV-AWEB5 (provided you have the capability and accessibility, etc.) then you'd be able to RDP using the listener name (mstsc /v:YourListenerName). It's just a VNN.
The return of that would be the computer name of your owning node.
By all of your symptoms, I'd be willing to bet that you've reached your failover threshold. The failover threshold determines how many times the cluster will attempt to failover your resource group in a specified time period. The default of these values max failovers n - 1 (where n is the count of nodes) in a period of 6 hours. You can see that through the following WSFC PowerShell command:
Get-ClusterGroup -Name "YourAgName" |
Select-Object Name, FailoverThreshold, FailoverPeriod
That just gives you the settings (which you can modify if you so choose, of course).
The best way to prove that this is the case for you, you would need to generate the cluster log (the system event logs only go into detail as far as " has failed", or something like that).
Get-ClusterLog -Node "YourClusterNode" -TimeSpan <amount_of_minutes_since_failure>
That'll by default get put into the "C:\Windows\Cluster\Reports" folder, and the file is called "Cluster.log".
If you were to open up that cluster log, you should be able to find the following string in there, indicating exactly what happened and why it happened:
Not failing over group [YourClusterGroupName], failoverCount [# of failovers], failover threshold [failover threshold value], nodeAvailCount [node available count].
The above message is simply WSFC telling you that it will not failover your group because it's happened too much (you hit the threshold).
Why does this happen? Simply to prevent the Ping-Pong effect of cluster resources going back and forth too frequently between nodes.
Whereas this would be common to hit these thresholds in failover testing, in production it would typically point to a problem that should be investigated.
Simply put, if you have, or can create, a Windows Server Failover Cluster setup across the data centres as a stretch cluster, then there is no reason why this is won't be possible. The fact the DC's are geographically dispersed is irrelevant. Good networking can bring them together as if they were not.
You could also do this as a SQL Cluster, with replication across the disks, and the disks presented to the cluster as a shared cluster resource.
I think you need to read up on the Pro's and Con's of each solution, and maybe speak to a Windows Server and/or Networking professional.
Best Answer
I think what you are trying to achieve via powershell is for planned manual failover as mentioned in msdn link. here
And what you exactly are trying to achieve " failover between async replicas " is more of forced manual failover with/without data loss which can be achieved via TSQL as mentioned in same msdn link. I don't see PS there but may be someone here who have used can answer. I am not sure but may be you can check dbatools if it provides one
Go through the steps as mentioned laster in that article