Error 25085 – Setup failed to register VMware Update Manager extension to VMware vCenter Server

I upgraded my vCenter to 4.1u1 while my VUM was still 4.0 (u2 iirc).  I decided to upgrade my VUM to match, and all was going well until I got this message:

Error 25085 – Setup failed to register VMware Update Manager extension to VMware vCenter Server

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Script I needed to get info for multiple VMs = Get-VMInfo.ps1

I’ve recently had a ton of requests for information about specific VMs. They want to know how many disks they have, CPU count, how much RAM, and which environment the VM resides in.

Instead of constantly searching vCenter, I wrote this quickly during the meeting to query multiple servers.
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DRS Host affinity in 3x & 4.0 – keeping a VM from migrating to a different host

Using DRS in vSphere is a great thing for load balancing your cluster, but what if you need to keep one VM from vMotioning to another host?  Everyone mention’s host affinity when searching, but digging through the DRS settings doesn’t really show much.

The closest thing to ‘Host Affinity’ is this KB article from VMware.

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System Error: vmodl.fault.hostcommunication

I upgraded one of my lab hosts to ESXi 4.1 yesterday and was plagued with this error:

System Error: vmodl.fault.hostcommunication

vmodl.fault.hostcommunication

A lot of people are getting this error without a lot of direction. As it turns out, this is because I upgraded one of my hosts to 4.1 without upgrading vCenter to 4.1. Silly me! Who would have thought that vSphere vCenter couldn’t manage a vSphere host because it’s rev is 0.1 higher?

VMware vSphere 4.1 Configuration Maximums

ESXi 4.0 Update 1 brought with it one major update (as I pointed out here). Now that 4.1 was released on July 13th, I wanted to take a look and see if anything else major has been changed.

Biggest change was they lifted the 160 VMs per host in an 8-node HA cluster.  Now it’s the maximum of 320 VMs per host, and a maximum of 32 nodes per HA cluster.  Problem is, they imposed a maximum of 3000 VMs per cluster (standard, HA, or DRS, they no longer differentiate them), so you’d just have to find your sweet spot to maximize how you want your cluster set up.  Not that 3000 VMs per cluster is a problem, but if you ran 320 VMs on 75% of a 32-node cluster (leaving 25% for failover), that’s 7680.  That’s a difference of 4680 VMs.  At any rate, I’m glad they lifted the 40 VMs per host in a 9+ configuration.

The Configuration Maximums for 4.1 can be found here.

Here are some of the key features that have changed:

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VMware ESXi 4.1 brings Scripted Installs!!

This is a welcomed (and much demanded) added feature to ESXi. I talked about the deployment of multiple ESXi hosts previously and how I used a golden image to lay down on individual SD cards.

It’s currently supported using a boot CD or PXE. However, the scripted installation is only for local or remote disks, installation on USB devices (SD cards, etc), isn’t currently supported.

It’s very similar to ESX, in that it uses a kickstart file to load the OS, and can be pulled from all the typical locations (FTP, HTTP, NFS, USB, etc).

At least this is a huge step in the right direction.

For more information on the install of ESXi 4.1, see chapter 5 of this doc.