SqlAG/SqlAGReplica: Logic

[Zuldan]

Details of the scenario you try and problem that is occurring:

I hope this comes across without sounding too confusing....

At the moment xSQLServerAlwaysOnAvailabilityGroup and xSQLServerAlwaysOnAvailabilityGroupReplica are trying to enforce defaults even when a property is not set but I think it should not check the state of a property if it's not defined in the DSC resource. I would like my DBA's to have control over certain properties and not DSC.

Here is an example.

If I don't set the FailoverMode in xSQLServerAlwaysOnAvailabilityGroup then the resource will enforce 'Manual' mode. So if a DBA gets a call from the network guy to say there will be some network maintenance, the DBA might want to change FailoverMode to Automatic so he doesn't get a phone call in the middle of the night. The problem is now DSC will revert the FailoverMode to Manual even though I haven't specified it in the config.

The "Desired State" should only be what I define in the config. If the properties are not defined then they shouldn't be enforced. @johlju what are your thoughts?

The DSC configuration that is using the resource (as detailed as possible):

N/A

Version of the Operating System, SQL Server and PowerShell the DSC Target Node is running:

Server: Windows 2012 R2 (Update)
SQL Server: 2016 SP1 CU2
Powershell: 5.1

What module (SqlServer or SQLPS) and which version of the module the DSC Target Node is running:

SqlServer v20.0

Version of the DSC module you're using, or 'dev' if you're using current dev branch:

7.0.0.0

[johlju]

@Zuldan I agree with this. If you haven't set a property it shouldn't enforce it. The problem you are having is that the line 659 is seeing the default values as well and are trying to enforce those default values. It should not do that. Default values should only be used during setup.

@randomnote1 What are your thoughts on this?

[randomnote1]

@Zuldan, this makes complete sense to me. When I wrote the resource I had to use default values in order to build the AG, but it didn't occur to me that somebody might not want the default enforced. This will take some work to change, particularly on the unit testing side.

Thanks for using & testing these! Glad to know there's some interest in the resources.

[Zuldan]

@randomnote1 any chance you would have time to make this change before the next release? We're currently getting through the issue by temporarily disabling DSC on the SQL clusters when we need to manage settings not configured by DSC. Not an ideal situation lol. Any improvements you could make to this would be greatly appreciated.

[randomnote1]

I don't think it's likely in the short term. I have a few weeks of vacation coming up plus some other projects for my day job that need attended to.

[Zuldan]

@randomnote1 that's ok I understand. Appreciate all your work so far forgetting these modules together.

[randomnote1]

"Accidentally" started fixing this for xSQLServerAlwaysOnAvailabilityGroup while working issue #468.

[johlju]

Great @randomnote1! Labeling this as in progress.

[Zuldan]

@randomnote1 fantastic news! :-)

[johlju]

@randomnote1 Can you confirm that this was fixed in PR #853 (or any another PR)? If so let's close this issue, if not, then I change the label back to 'Help Wanted'.

[randomnote1]

Yes, this was fixed in PR #853. I must have missed this issue when I created the resolved issues list!

[johlju]

No worries. Thanks for confirming! Closing,