VM node Restrictions

[lowerym]

So reading about the HA groups and being able to have select VMs only run on the selected nodes. great feature. however i may have missed it or it may not be there, But is there a way to setup VM restriction groups?

Example. I have 4 nodes. and 3 VMs

the 3 VMS can run on any of the 4 nodes, but I don't want them to be able to run on the same node as the either of the other 2 VMs

 

[t.lamprecht]

You mean HA service dependencies?

No, that's currently not possible directly, albeit there was some enhancement request already in the past and it can be a sensible feature in general.

You can workaround by creating two groups, each assigned only two nodes and thus split those which should not run on the same node with that. You can always add the other nodes as fallback for the failure case, but with 3 or 4 nodes only one can fail anyway, so in your specific scenario it would not matter.

 

[lowerym]

Thank you for the reply on this. Hopefully it is something you consider as a feature in the future.

 

[ermanishchawla]

So reading about the HA groups and being able to have select VMs only run on the selected nodes. great feature. however i may have missed it or it may not be there, But is there a way to setup VM restriction groups?

Example. I have 4 nodes. and 3 VMs

the 3 VMS can run on any of the 4 nodes, but I don't want them to be able to run on the same node as the either of the other 2 VMs

You meant anti-affinity rules. Currently we configure this by creating 2 groups. Each with different nodes and assign VM of similar category to different group.

Automatic balancing of VM based on resource pool or group of VM through straight forward method would be an ideal scenario

Also a feature to automatic balance the VM across the nodes configured in group would be best

 

[pascalc]

typically for an elasticsearch cluster of 3 vm, we want each vm to always be on a different pmx node (for ha purpose of the ES cluster).

 

[lowerym]

ElasticSearch and Redis are the use cases i have as well

 

[ermanishchawla]

If you want elastic search to be on 3 different machine in normal scenario in 4 node setup

do the following

Group 1 : <host>:<priority> syntax if you follow

Group1: Node1 Priority 2, Node2: Priority3 : Node3 Priority4. == Assign ElasticSearch VM1
Group2: Node3 Priority 2, Node2: Priority3 : Node1 Priority4. == Assign ElasticSearch VM2
Group2: Node4 Priority 2, Node3: Priority3 : Node2 Priority4. == Assign ElasticSearch VM3

VM shall be deployed as per priority flag

Also enable fallback option