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Step 3. How to do it via ILO. <br />
Also do i have to remove the esx host from cluster or data center if upgrading, so that other things do not stop. How will I rmember to what LUN or Datastore I have moved the VM. Any precautions?
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Step 3. How to do it via ILO.
Also do i have to remove the esx host from cluster or data center if upgrading, so that other things do not stop. How will I rmember to what LUN or Datastore I have moved the VM. Any precautions?

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I have to make a plan for ESX host upgrade from 5.1 to 5.5 version in an production environment. Could I please get help how to do it. There are many hosts. I have to upgrade entire DATACENTER.
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I have to make a plan for ESX host upgrade from 5.1 to 5.5 version in an production environment. Could I please get help how to do it. There are many hosts. I have to upgrade entire DATACENTER.

ESX UPGRADE

VMware, a software company founded in 1998,  was one of the first commercially successful companies to offer x86 virtualization. The storage company EMC purchased VMware in 1994. Dell Technologies acquired EMC in 2016. VMware’s parent company is now Dell Technologies.

VMware has many software products that run on desktops, Microsoft Windows, Linux, and macOS, which allows the virtualizing of the x86 architecture.  Its enterprise software hypervisor for servers, VMware vSphere Hypervisor (ESXi), is a bare-metal hypervisor that runs directly on the server hardware and does not require an additional underlying operating system.