I have 4 ESXi 5 servers in a VMware ESXi 5 environment; each server has 6-8 Windows 2003/2008 guest servers. This has been up and running for about 1 year. I would now like to create 1 cluster which would include all 4 ESXi servers. I want to do this to so we can take full advantage of the HA and failover capabilities. I now know that I should have set this up from the beginning. If I were to do this now is there anything I should be watching out for. Should I shut down all my guests first, if I do not shout down all the guest will there be any issues? I’m looking for the best approach in moving forward with this. Also, I have found some documentation on blogs etc. regarding what settings to set during the setup of the cluster but they don’t seem to be in agreement so if anyone has the official VMware recommendations that for the specific settings in the cluster that would be appreciated as well.
There is no need to shutdown guests to add a host to a cluster.
You just need to cleate cluster first. (Do not enable the cluster first by tick HA or DRS)
Drag and Drop hosts to one by one to the cluster.
Once Hosts are inside the cluster go to edit cluster and enable the cluster.
My advise for you is get some advise regarding designing the cluster.
Since its so easy how vmware have made creating cluster in vsphere people tend to crate clusters and add hosts to them and having hard time on figuring out cluster parameters and some tring to figure out why some VMs did not restarted due to a faliure.
so friend do your planing first.
Good Luck...!
NJ
Should I shut down all my guests first, if I do not shout down all the guest will there be any issues?
No need to shutdown your guests.
when you drag in your host to the cluster, the guests stay running
there should be no issues at all.
There is no need to shutdown guests to add a host to a cluster.
You just need to cleate cluster first. (Do not enable the cluster first by tick HA or DRS)
Drag and Drop hosts to one by one to the cluster.
Once Hosts are inside the cluster go to edit cluster and enable the cluster.
My advise for you is get some advise regarding designing the cluster.
Since its so easy how vmware have made creating cluster in vsphere people tend to crate clusters and add hosts to them and having hard time on figuring out cluster parameters and some tring to figure out why some VMs did not restarted due to a faliure.
so friend do your planing first.
Good Luck...!
NJ
Gentlemen, gentlemen, gentlemen!
This is just so not entirely true! There is one extremely important cluster feature you must be aware of or else this vMotion train is *not* leaving! Unfortunately, I have no way of testing it outside of just trying it.
I guess it's important to say that strictly speaking, vMotion compatibility is not mentioned in the original post, but bearing in mind the *spirit* of the question, who doesn't want vMotion in their cluster!?
All hosts in a cluster - and their VMs, must be running at a certain EVC baseline. What I mean by VMs running at certain EVC baseline (since you don't enable EVC at the VM level) is that they cannot be running CPU instructions that are *not* supported by the EVC/CPU baseline that the cluster is running. EVC is (or compatible CPUs are) mandatory for vMotion compatibilty. Although you don't *have* to have EVC enabled in a cluster, if you have non-identical CPUs running in the cluster, EVC will be very useful.
If your VMs are running on hosts at a higher/newer EVC baseline or CPU compatibility than those hosts in the cluster, you'll have to incur VM downtime. VMs determine their ability to run on certain CPU at boot time, so if there are incompatible EVC or CPU baselines, you're VMs are going to see downtime because they'll need to be powered off then powered back on, completely power cycled, to notice the change in CPUs.
You'll want to verify the CPU architecutures of each host you want to include in the cluster. If they're different enough, you'll have to work out a leap-frog-type switch-over to the hosts in the cluster.
Although you *can* vMotion from an independent host to a host in a cluster, vCenter will tell you that a particular vMotion is not possible because of CPU incompatibilities in which case, you'll just shut down the VM, migrate it (or un-register/re-register), then power it back on on the cluster host.
As a final thought, HA will work just fine without vMotion capabilities because VMs are *restarted* during an HA event - not live-migrated.
Cheers,
Mike
https://twitter.com/#!/VirtuallyMikeB
http://LinkedIn.com/in/michaelbbrown
