Guys,
I have 2 VMs (Domain controllers) and I would like to separate these VMs between hosts in a cluster. I have created DRS rule with a "Separate Virtual Machines" policy. But I can migrate these VMs to the single host using vMotion.
How to protect VMs against migration to a single host? I would like that DRS still working for these VMs.
I have a stupid question, but is the check mark checked next to the DRS rule to activate it?
Can you share the screenshot of current DRS rule config?
Which vCenter version do you use? Please take a look at vSphere 5.5 nuggets: High Availability Enhancement to see whether this helps.
André
Andre, I use 5.5 version.
Duncan's post says that we should to enable this feature for HA (and yes, this feature is enabled in the infrastructure), but it is not affected DRS rules or vMotion.
Is DRS set to fully automated? Is Admission Control Enabled?
Admission Control is enabled.
DRS is set to manual.
I can set to fully automated policy, and DRS will migrate domain controller to another host (In case if two VMs are placed on a single host).
But if I use vMotion I don't get any notification about "separate VM" policy, and I can place two VMs on a single host.
VM VM anti affinity rule is soft rule. User initiated operation can violate this rule. Also if it is absolutely required, DRS also may violate this rule for balancing the cluster. However, in both cases, DRS will make best efforts to correct the violation in the next DRS invocation. Vm-Host hard rules are mandatory, mandatory rules even does not allow manual vMotion which violates the rule. HA also will honor the rule.
VM VM anti affinity rule can be made HA aware by using advanced option (Duncan's blog talk about that)
You won't get a warning about the Anti-Affinity rule. If you vMotion one of the VMs to that host, DRS will vMotion the other one off. If DRS is set to manual, It will allow both to live together.
You need to have DRS set to Automated for it to do what you want.
Thank you, Guys. I get it.
I will think how to change my DRS policies.
Go to cluster configuration tab VM/Host Rules and set new rule for separate or together machines.