About_DRSRule.help.txt
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about_DRSRule SHORT DESCRIPTION The DRSRule module allows you to work with all types of vSphere DRS rules. The module works with affinity/anti-affinity VM rules and VM to VMHost rules. The module provides support for VM and VMHost groups. LONG DESCRIPTION The DRSRule module was written to provide PowerShell support for all types of DRS rules that are available. The module leverages some of the VMware PowerCLI cmdlets, and requires that PowerCLI is installed on the Windows machine on which the DRSRule module shall be used. DRSRule CMDLETS The DRSRule module contains the following cmdlets. New-DrsVMGroup Create a DRS VM group New-DrsVMHostGroup Create a DRS VMHost group New-DrsVMToVMHostRule Create a DRS VM to VMHost rule New-DrsVMToVMRule Create a DRS VM to VM rule Get-DrsVMGroup Retrieve DRS VM groups Get-DrsVMHostGroup Retrieve DRS VMHost groups Get-DrsVMToVMHostRule Retrieve DRS VM to VMHost rules Get-DrsVMToVMRule Retrieve DRS VM to VM rules Set-DrsVMGroup Change a DRS VM group Set-DrsVMHostGroup Change a DRS VMHost group Set-DrsVMToVMHostRule Change a DRS VM to VMHost rule Set-DrsVMToVMRule Change a DRS VM to VM rule Remove-DrsVMGroup Remove a DRS VM group Remove-DrsVMHostGroup Remove a DRS VMHost group Remove-DrsVMToVMHostRule Remove a DRS VM to VMHost rule Remove-DrsVMToVMRule Remove a DRS VM to VM rule Export-DrsRule Save all DRS groups and rules to a JSON file Import-DrsRule Import DRS groups and rules from a JSON file DRS Group and Rule Concept In vSphere DRS you can define "rules" that control the placement of virtual machines on hosts within a cluster. There are 2 types of rules: - affinity/anti-affinity rules between individual virtual machines - affinity/anti-affinity rules between groups of virtual machines and groups of hosts in a cluster The rules that define affinity/anti-affinity between a group of virtual machines and a group of hosts, can be a requirement ("shall") or a preference ("should") QUICK START To execute any of the following cmdlets from the DRSRule module, you need - to have loaded the PowerCLI module - to be connected to a vCenter The following command create a DRS VM affinity rule, on a cluster called MyCluster, between two virtual machines, called vm1 and vm2. The rule will be enabled. New-DrsVMToVMRule -Name 'Affinity Rule' -Cluster MyCluster -VM vm1,vm2 -KeepTogether -Enabled To create a VM anti-affinity rule, the KeepTogether switch needs to be set to $False. New-DrsVMToVMRule -Name 'Anti-affinity Rule' -Cluster MyCluster -VM vm1,vm2 -KeepTogether:$false -Enabled If you want to change a DRS VM to VM rule, for example to replace virtual machine vm2 by another virtual machine called vm3, you can do the following Get-DrsVMToVMRule -Name 'Affinity Rule' | Set-DrsVMToVMRule -VM vm1,vm3 First you retrieve the rule, then you pass the DrsRule object over the pipeline to the Set-DrsVMToVMRule cmdlet. When a DRS VM to VM rule is not needed anymore, you can easily remove it. Get-DrsVMToVMRule -Name 'Affinity Rule' | Remove-DrsVMToVMRule -Confirm:$false Note that you will be prompted for a confirmation, if you leave out the Confirm switch. Another type of DRS rules handles connecting a group of virtual machines to a group of ESXi hosts. To use such a DRS VM to VMHost rule, you will first need to create the groups. A DRS VM group can contain one or more virtual machines. New-DrsVMGroup -Name 'VM Group' -VM vm1,vm2 -Cluster cluster1 As with all cmdlets in the DRSRule that have a New verb, the newly created group will be displayed. Name Cluster UserCreated VM ---- ------- ----------- -- VM Group Cluster1 True {VM1, VM2} You can change these groups with the following cmdlet Get-DrsVMGroup -Name 'VM Group' | Set-DrsVMGroup -VM vm3 -Append The use of the Append switch determines if the virtual machines that you specify on the VM parameter will be added to the virtual machines that are already defined in the group, or if they will replace the virtual machines. The ouput for the previous line will be Name Cluster UserCreated VM ---- ------- ----------- -- VM Group Cluster1 True {VM1, VM2, VM3} In a similar way you can create a DRS VMHost group New-DrsVMHostGroup -Name 'VMHost Group' -VMHost esx1*,esx2* -Cluster cluster1 Notice how the values we pass on the VMHost parameter contain a masking character. This avoids having the type the full vmhost name. On the console you will see Name Cluster UserCreated VMHost ---- ------- ----------- -- VMHost Group Cluster1 True {esx1.local.test, esx2.local.test} Now that we have a VM and a VMHost group, we can create a DRS VM to VMHost rule. If we want these virtual machines to always run on these ESXi nodes, we can define a DRS rule as follows. $ruleSplat = @{ Name = 'Required Affinity' AffineHostGroupName = 'VMHost Group' VMGroupName = 'VM Group' Cluster = 'cluster1' Mandatory = $True } New-DrsVMToVMHostRule @ruleSplat Notice how we used 'splatting' to specify the parameters for the cmdlet. This example creates a required VM to VMHost rule, that is accomplished by the Mandatory switch. If we want to change the rule we created in the previous example, we have a couple of options. We can retrieve the rule, remove it and then create the new DRS VM to VMHost rule. Get-DrsVMToVMHostRule -Name 'Required Affinity' | Remove-DrsVMToVMHostRule -Confirm:$False $ruleSplat = @{ Name = 'Required Affinity' AffineHostGroupName = 'VMHost Group' VMGroupName = 'VM Group' Cluster = 'cluster1' Mandatory = $True Enabled = $False } New-DrsVMToVMHostRule @ruleSplat Or we can use the Set cmdlet. Set-DrsVMToVMHostRule -Name 'Required Affinity' -Enabled:$False But there is a third option, where the Force switch allows you to replace an existing DRS rule directly with the New cmdlet. $ruleSplat = @{ Name = 'Preferred AntiAffinity' AntiAffineHostGroupName = 'VMHost Group' VMGroupName = 'VM Group' Cluster = 'cluster1' Mandatory = $False Force = $True } New-DrsVMToVMHostRule @ruleSplat There are many occasions where you want to be able to export and import your DRS groups and rules. The DRSRule module provides this functionality with two cmdlets. These cmdlets use a JSON file to store and retrieve your DRS rules and groups. To export your DRS rules and groups, you can do Export-DrsRule -Cluster cluster1 -Path drs.json This will export all DRS rules and groups that are defined on Cluster1, to a JSON file in your current directory. To import these DRS rules and groups, you can do Import-DrsRule -Path drs.json -Cluster cluster1 SEE ALSO https://pubs.vmware.com/vsphere-55/topic/com.vmware.vsphere.resmgmt.doc/GUID-FF28F29C-8B67-4EFF-A2EF-63B3537E6934.html http://blog.pluralsight.com/vmware-storage-drs-rules |