Yellow Bricks

by Duncan Epping

VirtualCenter

Virtual Machines appear to be running or registered on multiple ESX Servers

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I was doing my daily round on the VMTN Forums and noticed this topic on VMs flickering between ESX hosts. I’ve personally never witnessed this and didn’t even knew it was a known issue. Luckily Troy Clavell pointed the topic starter out to a KB article related to this exact issue. Apparently it’s being caused by the fact that the VM is registered on two hosts at the same time.

Symptoms:

  • After one of the following, a Virtual Machine appears as being registered on two ESX Servers:
    • A VMotion fails to complete correctly or times out in VirtualCenter
    • A DRS issue where virtual machines are VMotioned automatically in quick succession
    • When a machine is powered on during VMware HA failover.
    • The Service Console on an ESX host is low on memory starving the vpxa process
  • In VirtualCenter, you see the virtual machine as appearing on one ESX Server for a few seconds, then it seems to be on the other.
  • The virtual machine may appear to jump back and forth among different ESX hosts.

I’m not going to copy/paste the solution cause the KB article will probably change over time, but it’s most definitely worth looking into… it does sound like something that can happen to all of us.

Train Signal virt CBTs still 25% reduction

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A couple of weeks ago I wrote about Train Signal, the post included a reduction coupon, YELLOWBRICKS. This coupon gives you 25% reduction on the Train Signal virtualization CBTs. Train Signal was so kind to also provide me with an additional coupon that gives you free shipping:

All you need to do is head over to Train Signal and enter the following coupon code “YELLOWBRICKS” and “FREESHIP”. By buying a CBT you also support Yellow-Bricks.com! Both coupon codes are valid till the end of the month, just two weeks left…

vCenter and SQL service dependencies

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During several projects I noticed that for some reason the vCenter service would not start correctly. After a quick browse in “services.msc” and the eventlog I noticed that the vCenter service started before the SQL service. As you can imagine vCenter needs SQL to be up and running before it can actually start. I fixed it by creating a dependency. For some weird reason I never blogged this, but today I noticed this KB article that describes how to set up this dependency:

Adding a dependency to the VirtualCenter service so that it waits for SQL Express remedies this.

To create a service dependency:

  1. Click Start > Run.
  2. Type services.msc and press Enter.
  3. Locate the SQL Express instance for VirtualCenter. For example, SQL Server (SQLEXP_VIM).
  4. Open the SQL Express instance and note the Service Name. For example, MSSQL$SQLEXP_VIM .
  5. In the Run dialog, type Regedit.exe and press Enter. Browse to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\vpxd .
  6. Double-click the DependOnService key and add the Service name using the name identified in step 4.
  7. Close Regedit .
  8. Go back to the Services Panel and open the SQL Server properties.
  9. On the Dependencies tab, verify the VMware VirtualCenter service is listed as depending on the SQL service instance.

As you can see the solution is fairly easy. Keep in mind that you need to be running the SQL Server locally on the vCenter server for this to work, especially for larger environments I wouldn’t advise running both on the same box. For SMB environments this should work just fine.