#Vcenter 6.5 cluster different plus

We also briefly explain some of the technical details behind these improvements. power-on virtual machine)ДЄs senior engineers within the VMware Performance and vSphere teams, we are writing this blog to provide more details regarding these numbers and to explain how we measured them. Moreover, with vSphere 6.7 vCSA delivers phenomenal performance improvements (all metrics compared at cluster scale limits, versus vSphere 6.5):ДўX faster performance in vCenter operations per secondДЈX faster DRS-related operations (e.g. Hopefully we will have something out вЂњsoonвЂќ, as in around VMworld.In a recent blog, the VMware vSphere team shared the following performance improvements in vSphere 6.7 vs. Oh, if you didnвЂ™t know yetвЂ¦ Frank, Niels and I are actively updating the vSphere Clustering Deep Dive. Note that the outcome is usually pretty big, so you will have to scroll through it to find what you need, if you do a search on вЂњ restartPriorityвЂќ then you should be able to find it the VMs for which you changed the priority. You can examine this on the commandline by the way by typing the following: /opt/vmware/fdm/fdm/prettyPrint.sh clusterconfig All of this info is stored in the cluster configuration data. So you can use it even to ensure vCenter, AD and DNS are booted up first. Then select the new priority and specify when the next batch should startДЄnd if you are wondering, yes the restart priority also applies when vCenter is not available.

#Vcenter 6.5 cluster different plus

Click on the green plus sign and select the VMs you would like to give a higher, or lower priority.

Click on вЂњVM OverridesвЂќ and then click вЂњAddвЂќ.

Click on your HA cluster and then the вЂњConfigureвЂќ Tab.

So where do you change this? Well that is pretty straight forward: In other words, changing the restart priority only makes sense when you have VMs at different levels, and usually will only make a big difference when you also change the option вЂњStart next priority VMs whenвЂќ. Simply because the restart priority is about the priority between VMs, it doesnвЂ™t change the host response times etc. By default all VMs will have the вЂњmediumвЂќ restart priority, and no it wonвЂ™t make any difference if you change all of them to high. Why these funny names? Well that was done in order to stay backwards compatible with vSphere 6 / 5 etc. Instead of the 3 standard restart вЂњbucketsвЂќ you now have 5: Highest, High, Medium, Low, Lowest. Now when you have made your choice around when to start the next batch you can simply start adding VMs to a specific level.

Note that with option 4 you will need to have VM/Application Monitoring and defined within the VM. So if it is important for the вЂњservice providedвЂќ by the VM to be available before starting the next batch then option 3 or 4 would be your best pick. In some cases it could take 10-20 seconds for a VM to be fully booted and the apps to be available, in other cases it may take minutesвЂ¦ It all depends on the services that will need to be started within the VM. Very similar for VMs are powered on, this also says nothing about when a VM is available. I think these are mostly self-explanatory, note though the вЂњresources are allocatedвЂќ means that a target host for restart has been found by the master. Especially this last part is important, as this allows you to specify that we start with the next priority level when: (Simply because we can schedule many at the same time, and the priority would as such have no effect.)ДЄs of vSphere 6.5 we have the ability to specify the priority and also specify when HA should continue with the next batch. Each host in a cluster can restart 32 VMs at the same time, so you can imagine that if the restart priority is only about VM restarts that it doesnвЂ™t really add a lot of value.

It has always been possible to set a restart priority for VMs, but pre-vSphere 6.5 this priority simply referred to the scheduling of the restart of the VM after a failure.

I already did in this post about whatвЂ™s new in vSphere 6.5 and I did so in the Stretched Cluster guide. I figured I would write something about it. IвЂ™ve seen more and more questions popping up about vSphere HA Restart Priority lately.