ESX 4.1 U2 upgrade: management network redundancy configuration issues

Last week one of our customers was upgraded from vSphere 4.0 to vSphere 4.1 Update 2. Indeed no vSphere 5 but that’s another story…

The customer wanted to update his vSphere environment at the lowest cost possible. Mainly because they will be upgrading their environment with new hardware and vSphere 5 after their high season, April/May next year.

To upgrade vSphere 4.0 to vSphere 4.1 the first thing needed is to be upgraded VMware the vCenter server. This meant we first needed to install Windows Server 2008 R2, because vSphere vCenter Server 4.1 can only be installed on a 64-bit Operating System.

The following blogs will help you upgrade your vCenter Server:

VMware Blog &

After this was done It was time to upgrade the ESX server in the environment. Here are some links for the ESX upgrade method I used:

VMware KB /

But after both vCenter and the ESX hosts were upgraded, in vCenter all hosts were showing the yellow warning signs:


The Summary tab, revealed the problem that caused those yellow signs:

Config Issues

A couple of years back the dissision was made to put the service console on a single NIC. And with upgrading to this version of vSphere this warning showed up. To remove this warning, there are a couple of options:

  • Adding an extra NIC to the vSwitch for redundancy
  • Add another Service Console port to one of the other vSwitches (requires an extra IP address)
  • Use the das.ignoreRedundantNetWarning to get rid of the warning

In the rest of this post I’ll focus on the last option. Setting the das.ignoreRedundantNetWarning is a very easy thing to do, but remember it’s not set false for fun. VMware has a good reason to set this value to False, but sometimes you don’t have antoher choice than to set this value to True.

Let’s add this value to get rid of the warning:

  1. Select your HA cluster right click (Step 1) and click on Edit Settings (Step 2)
  2. Right click
  3. Select vSphere HA (Step 1) and click on Advanced Options… (Step 2)
  4. HA settings
  5. In the Advanced Options screen double click on a blank line under the Option tab and add the das.ignoreRedundantNetWarning (Step 1) and under Value True (Step 2)
  6. Advanced settings
  7. Click OK in the Advanced Options window and OK again in the Cluster settings
  8. Select the ESX host and right click (Step 1) and click on Reconfigure for VMware HA (Step 2)
  9. reconfigure
  10. The host will be reconfigured and the warning will disappear
  11. 2011-11-23 10h05 56 Done!

For more information make sure to visit the following sites: