Troubleshooting

Troubleshooting can often be frustrating and challenging, and knowing where to look and what to do is the key to quickly finding and resolving problems. You shouldn’t just look through log files when you are experiencing known problems, however. Often, many problems might not be that obvious, and the log files are a good place to look for signs of them happening. You should keep a list of all the log files handy so that you can quickly access them if needed and so not have to waste time when a problem is happening trying to remember their path and filenames. You might not know how to resolve or troubleshoot every problem you encounter, so be sure to rely on the resources available to you, including documentation, support forums, knowledge base, and VMware’s technical support. Being properly prepared to handle problems when they occur is one of the best troubleshooting skills that you can have.

What you can do

• Check Monitoring Systems if you have them. SCOM, Nagios etc. Some companies have real-time screens showing monitoring
• Check with your Network Team as they will more than likely be alerted to physical problems faster than you
• Can you isolate the problem to a VM, Host, Switch or router or is the issue affecting the whole network
• Ensure that the Port Group name(s) associated with the virtual machine’s network adapter(s) exists in your vSwitch or Virtual Distributed Switch and is/are spelt correctly.
• Check any warning Triangles or exclamation marks on the standard or distributed switches
• Verify the virtual network adapter is present and connected for all VMkernel ports
• Verify that the networking within the virtual machine’s guest operating system is correct
• Verify that the vSwitch has enough ports for the virtual machine
• Ensure the physical switch ports are configured as port-channel
• Shut down all but one of the physical ports the NICs are connected to, and toggle this between all the ports by keeping only one port connected at a time. Take note of the port/NIC combination where the virtual machines lose network connectivity.
• Check Logs