can you advise the steps to upgrade vcenter and ESXi running on 2 Node HA Cluster without downtime to VMs
a migration approach is required as need to migrate windows vcenter to appliance with all configurations
Vcenter 5.5- Windows Server
2 ESXi 5.5
The upgrade strategy in this case is as below:
Before to start the upgrade process, it is recommended to check your host compatibility with the target version through the VMware Compatibility Guide: VMware Compatibility Guide - System Search
And regarding the vCenter upgrade also be careful if you have an external configuration. (external PSC and vCenter).
For more information check the following: https://docs.vmware.com/en/VMware-vSphere/5.5/vsphere-esxi-vcenter-server-552-upgrade-guide.pdf
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