Configuring Orchestrated Restart via PowerCLI

[StephenMoll]

Clearly this isn't possible using New-DRSRule as the 'KeepTogether' parameter is boolean which only allows for specifying an affinity or anti-affinity rule.

So is it even possible to define an Orchestrated Restart rule via PowerCLI?

If it is possible, how is it done?

[LucD]

Not 100% sure what you are actually referring to.

Is it the vSphere HA Restart priority of specific VMs?

That you can do with the Set-VM cmdlet and the HARestartPriority parameter.

[StephenMoll]

In the vSphere Webclient GUI, when creating a "VM/Host Rule" the dialogue has the following options:

Field	Content
Name:	text field for name of rule
Enable Rule:	Check box.
Type:	Drop down list with these choices:     "Keep Virtual Machines Together"     "Separate Virtual Machines"     "Virtual Machines to Hosts"    "Virtual Machines to Virtual Machines"

With "Virtual Machines to Virtual Machines" selected the rest of the dialogue changes to:

Field	Content
Description:	Virtual machines in the VM group {VM Group Name} will be restarted first. Virtual machines in the VM group {VM group name} will be restarted afterwards, when the cluster dependency restart condition has been met.
First restart VMs in VM group:	A drop down list of VM groups defined in "VM/Host Groups".
Then restart VMs in VM group:	A drop down list of VM groups defined in "VM/Host Groups".

The New-DRSRule commandlet in PowerCLI specifies the rule type as boolean value, which only allows for the creation of either "Keep Virtual Machines Together" or "Separate Virtual Machines" rules. I wanted to know if a "Virtual Machines to Virtual Machines" rule can be created in PowerCLI at all?

[LucD · Accepted solution]

Ok, got it.

No, there is no cmdlet for that, but you can easily write your own function for this kind of rule.

Something like this

$clusterName = 'MyCluster'

$ruleName = 'MyRule'

$ruleMandatory = $true

$firstGroup = 'group1'

$secondGroup = 'group2'

$cluster = Get-Cluster -Name $clusterName

$spec = New-Object VMware.Vim.ClusterConfigSpecEx

$newRule = New-Object VMware.Vim.ClusterDependencyRuleInfo

$newRule.VmGroup = $secondGroup

$newRule.DependsOnVmGroup = $firstGroup

$newRule.Enabled = $true

$newRule.Name = $ruleName

$newRule.Mandatory = $ruleMandatory

$newRule.UserCreated = $true

$ruleSpec = New-Object VMware.Vim.ClusterRuleSpec

$ruleSpec.Info = $newRule

$spec.RulesSpec += $ruleSpec

$cluster.ExtensionData.ReconfigureComputeResource($spec,$True)

[StephenMoll]

Thanks for that LucD, going to have a play with that and see what we can do with it.

Obviously a single rule can only have two groups of VMs, in which group is started and then the second.

If I have three VM groups, say VMG1, VMG2 and VMG3.

If I create 2 rules, one rule with VMG1 and VMG2, and the second rule with VMG2 and VMG3, what happens?

Do I get a start sequence with VMG1 then VMG2 and lastly VMG3, or does it just get messy somehow?

[LucD]

No, you should get the intended order VMG1, VMG2 and finally VMG3

[StephenMoll]

Brilliant, I'll give it a go.

What is the easiest way to to test this? Get all the VMs running on a host and then kill it?

[LucD]

Yes, have at least 3 VMs running on that ESXi node, each VM in a different group.
Then kill the node

[KenGould]

@LucD Is there a way to interrogate the existing VM to VM Dependency rules? Use case is to capture them, so that they can be reinstated in the case of a full site disaster.

I've poked around in the extensiondata of a cluster but not seeing it stored there.

[LucD]

These rules can be found under $cluster.ExtensionData.Config.Rule
This is an array of ClusterRuleInfoobjects
There are multiple types; ClusterAffinityRuleSpec, ClusterAntiAffinityRuleSpec, ClusterDependencyRuleInfo, ClusterVmHostRuleInfo, VirtualDiskAntiAffinityRuleSpec,VirtualDiskRuleSpec

[KenGould]

Thanks Luc. Not sure how I missed them when poking around! Appreciate the steer.