Upgrade from ESX 4.1U1 to ESXI 5.5

[ngwendk]

Hi there,

Pls assist... I have a standalone ESX4.1U1 host, that runs on IBM HS22 blade server, with SAN connectivity. The standalone host is currently hosting/running 2 VMs. The standalone ESX host is booting from local disks (HDD), and it is also connected to SAN storage - the 2 VMs are located on SAN storage. Im planning to upgrade the host to ESXi 5.5. Pls advise on the best way to upgrade the standalone host, without affecting my VMs. That means, I need to be able to startup my VMs after the upgrade with no issues. Pls advise in detail... which option below should I choose?

> Upgrade ESXi, preserve VMFS datastore

> Install ESXi, preserve VMFS datastore

> Install ESXi, overwrite VMFS datastore

[weinstein5]

Welcome to the Community - There is no upgrade path from ESX to ESXi it has to be a complete new install - as long as the VMs are stored on the SAN you should be fine - Install ESXi 5.x on to the hardware - after installed you will be able to access the VMFS datastores on the SAN

[ngwendk]

Thanks for welcoming me to the community, i've just joined - much appreciated. Thanks also for feedback... then I guess the better option would be <Install ESXi, preserve VMFS datastore>

Once the install is done, i will just have to add the VMs back to the inventory?

[abhilashhb]

Do you have 4.1U1 ESX or ESXi?

[weinstein5]

Yes that is correct -

[ngwendk]

@Abhilash

I have currently have ESX4.1U1...

[ngwendk]

Thanks, much appreciated...

[TriggerTrue]

Hi,

I have a similar situation except the datastore is a separate RAID volume on the server itself.  Can I install ESXi 5.5 on the 4.1 server and then access the existing datastore and add the existing VMs back to the inventory or do I need to export the VMs and then import them after the upgrade?  Thanks.

[marcelo_soares]

Yes you can. You can also add all VMs back with a simple command line, you can find it on my blog: How to register all VMs on all datastores with one command

[TriggerTrue]

Good to know, and thanks for the command line link.  I inherited two standalone ESX 4.1 servers with no vCenter.  I convinced the client to upgrade to Essentials 5.5.  I will be adding a vCenter appliance for management.  Sounds like I can just back up the VMs (just to be prudent) and upgrade each of the standalone hosts to 5.5, re-add the VMs and install the vCenter VM and I should be good to go. 

Thank you.