Category Archives: Troubleshooting

Configure IBM Blades (running ESX) and Cisco switches for failover

By | September 29, 2010

Using IBM Blades and Cisco switches to run your ESX enviroment? If yes, have you tested what happens if you unplug the network cables going into one switch? If you like me have bundled 2 or more cables going from one switch, to one backbone switch and done the same for the other switch, then… Read More »

Guest warning after upgrade to vSphere 4.1

By | September 25, 2010

After we upgraded to vSphere 4.1, the SCSI adaptor of all our WINXP guests changed from LSI Logic Parallel  to BusLogic Parallel. This change should normally not create any warnings or problems it VMware Tools are up to date. But after the upgrade all our WINXP guests got the following warning when powered on in… Read More »

Copy & Paste option is disabled in vSphere Client 4.1 – default

By | September 21, 2010

Yesterday we upgraded one of our vSphere Clusters to 4.1 – it went smoothly 🙂 But today the users reported that they weren’t able to use cut % paste between the guest and their computer using the vSphere Client (Console). After a quick google we found that VMware has tightened the vSphere security by disabling… Read More »

Restarting management Agent on ESX 3.x

By | November 25, 2009

Restarting the Management agents on ESX Server 3.x Login to the ESX host using SSH (or from COS) Type service mgmt-vmware restart. CAUTION Before restarting the Management Agent make sure that Automatic Startup/Shutdown is Disabled For more info see Restarting hostd (mgmt-vmware) on ESX Server Hosts Restarts Hosted Virtual Machines Where Virtual Machine Startup/Shutdown is Enabled… Read More »

Upgrading Windows 2008 from virtual HW 4 to 7 may cause problems

By | November 23, 2009

Just found this very interesting article describing a problem with Windows 2008 and ESX 4 virtual hardware version 7. In short the article states that you might have the disks go offline in a Windows 2008 VM if you Upgrade virtual hardware from version 4 to 7 Installing a new VM with virtual hardware… Read More »

Extend disk with snapshots – How to fix the error

By | October 29, 2009

Yesterday I by mistake extended a disk on a VM that had snapshots. Using vmkfstools. Kind of like this thread ( This resulted in the following PowerOn error: Failed to power on Servername on Host in Cluster: Cannot open the disk ‘/vmfs/volumes/LUN/Folder/VM.vmdk’ Reason: The parent virtual machine disk has been modified since the child was… Read More »

32-bit ODBC DSN required for vSphere running on 64-bit OS and MSSQL

By | September 29, 2009

Last week I upgraded a Virtual Center server from Win2003 & MSSQL 2000 (32-bit) to Win2008 & MSSQL 2005 (64-bit). During the installation of vCenter it asked for a 32-bit ODBC even though all the new systems was running 64-bit. After a some time on Google i found that Windows 64-bit also includes a 32-bit… Read More »

Black screen in a Windows VM or an a physical server

By | September 10, 2009

Over the past few months we have seen a few Windows servers with a black screen. Meaning You can’t see the logon promt You get a black screen when you connect with RDP We found that the problem was caused by a change in the Windows color scheme. The solution is to copy the color… Read More »