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Showing posts from August, 2013

Migrating an ESXi Host and VMs from one vCenter to Another

One of my customers was transitioning into a cloud service provider, and as such their ESXi infrastructure needed to be changed around to support this decision.  A fairly standard design element of a provider datacenter is to break up the environment into 2 vCenter environments; one for management elements and one for customer VMs.  As such, we stood up the second vCenter server... but then we had the challenge of how do we move the exiting customers into the new customer resource vCenter?

It wasn't that hard, although it took a little planning to ensure that we didn't cause any service disruption to the VMs that were already running.  Adding to the complexity of the move was the fact that Distributed vSwitches were in use at this site.  Given that vCenter owns the Distributed vSwitch, we weren't sure how the system would behave if we simply took over ownership of the ESXi servers into the new vCenter, so we settled on the following procedure:

Remove vShield components from…

Orphaned VMDK Files

(8/10/2015) Update: Unfortunately, some backend things have changed since I originally cobbled this script together and it doesn't work any more.  I'll fix it if I get the chance, but in the meantime, there's a free utility called RVTools that can identify orphaned VMDK files (which are entertainingly called Zombie VMDKs on the vHealth tab of the application).  That's a great application to be aware of anyway, as it makes it very easy to get access to a lot of important information that the vSphere client obscures.

(11/9/2015) Update: I went ahead and put together a post detailing how I used RVTools and a helper script to identify, rename and then delete orphaned VMDK files.

Every organization has to wrestle with orphaned VMDK files.  What is an orphaned VMDK file, you ask?  It's a VMDK file that's sitting on your SAN, consuming expensive storage, but isn't actually being used by any VM.  They're notoriously hard to find (especially in larger environment…

VM NIC Hardware Failure Issue

A few customers have been hit by an intermittent issue where virtual machines seem to reject their network adapters.  In Windows, this shows up as the guest OS reporting a hardware failure on the NIC (which, given that the NIC is virtual, is bit of a hard sell).  So, while the VM has a network adapter attached to it and it is connected to the network, the VM doesn’t get any network access.  If you open up device manager, the “general tab” for the network adapter will show an error (error 10 if memory serves).  When you try to update the driver on the NIC, it will fail to install it.  I’ve only ever seen this with the vmxnet3 adapter, but I’ve heard that it can affect e1000 as well.

Typically, the VM’s network connectivity can be restored by some combination of removing the vNIC from the VM and adding it back (well, it’s technically a new one as it will have a new MAC address), reinstalling the VMTools and/or removing nonpresent NICs from the guest OS.  There doesn’t seem to be any co…