VMWare

We experienced an unusual fault today, it started out with remote users complaining about voice quality from their Cisco IP phone and remote desktop was dropping out. At first I thought it was a network problem as the users connect via a Cisco router IPsec VPN.

While I was checking the main router, local users started complaining about voice quality,  which changed my focus to the pbx (Asterisk running on Linux). I connected an IP phone directly to the pbx and voice quality as good so I moved onto the switches. I noticed port 20 was intermittently changing between amber and green so I removed the cable and all the problems disappeared. I could replicate the problem on any port so it was not the switch.

I traced the network cable back to our VMWare hosts first network adapter which is assigned to the Management Network.  Now I needed remove the faulty one and assign another adapter to the management network.

Here is how I did it, I hope this helps someone else.

1. I logged in to the VMWare host console via the IBM Integrated Management Module KVM (you may have some other connection method)

2. Select Configure Management Network and pres enter

3. Select Network adapters and press enter

4. Un-check the faulty one by highlighting it and pressing the spacebar

5. Select the one you want to use and press the space bar

6. I received this warning message, this did not concern me as I knew the adapter was not assigned to any guest so I pressed enter.

7.  This part of the following message did concern me “In case IPv6 has been enabled or disabled this will restart you host”. I did not find this very clear, I am not using IPv6, will it restart my host? To be safe shutdown your virtual machines first. My VMWare host did not restart and all was ok.

Now I can call IBM and get them to replace the Network adapter

I received this error when changing a TCP/IP settings on a VMware virtual machine that was converted from a physical to a virtual machine.

The IP address you entered for this network adapter is already assigned to another adapter.

You may also get this message; Cannot rename this connection. A connection with the name you specified already exists. Specify a different name.

The problem is a hidden network adapter with the same connection name or TCP/IP setting.

This is how I fixed it;

1. Click Start, click Run, type cmd.exe, and then press ENTER.
2. Type set devmgr_show_nonpresent_devices=1, and then press ENTER.
3. Type Start DEVMGMT.MSC, and then press ENTER.

4. Click View, and then click Show Hidden Devices.
5. Expand the Network Adapters tree.
6. Right-click the dimmed network adapter, and then click Uninstall.