Networking Troubleshooting

Question 1

What command can be used to list physical network adapters’ properties and statuses?

Answer 1

esxcli network nic list

Question 2

What commands can be used to list the vSwitch and dvSwitch information for an ESXi host?

Answer 2

esxcli network vswitch standard list

esxcli network vswitch dvs vmware list

Question 3

List the steps involved in troubleshooting virtual switch and port group configuration issues

Answer 3

• Verify that the virtual switch has not lost connectivity to the physical network.
  ■ Verify that the virtual switch has enough ports available.
  ■ Verify that VMkernel networking is configured correctly and that the IP address and
  subnet mask information are both correct.
  ■ Verify that the port group is configured to use the correct VLAN(s), if applicable.
  ■ Verify that the correct use case is selected: vMotion, FT, management traffic, or no
  selection for network storage.
  ■ If jumbo frames are used, verify that they are configured properly on the vSwitch and
  are enabled from end to end.
  ■ Verify that the remote addresses can be reached with the vmkping command in the
  ESXi Shell.
  ■ Verify that traffic shaping is configured properly, if applicable.
  ■ Verify that NIC teaming is configured as required for the environment.
  ■ Ensure that the ESXi firewall is configured correctly.

Question 4

List steps to verify virtual machine networking

Answer 4

Verify that the virtual machine has a network adapter, that it is connected, and that the
virtual machine is using the correct network label in the virtual machine properties.
■ Verify the virtual machine’s network adapter type and check to see whether the guest
OS has the required drivers installed.
Verify that other virtual machines using the same virtual machine connection type are
working properly.
■ Verify the networking configuration inside the guest OS is correct, including testing
the TCP/IP stack.
■ Verify that the virtual switch has not lost connectivity to the physical network.
■ Verify that the virtual switch has enough ports available.
■ Verify that the virtual switch is configured to use the required VLAN(s).

Question 5

List the 4 ways esxi host logs can be viewed

Answer 5

vSphere Client Administration, vSphere Web Client, DCUI and var/run/log via ESXi Shell

Question 6

List the troubleshooting flow for an ESXi host as defined by VMware

Answer 6

1. Check the VMware Tools status in the virtual machine.
2. Check the ESXi host CPU usage.
3. Check the virtual machine CPU usage.
4. Check for ESXi host swapping.
5. Check storage usage.
   6 Check ESXi for dropped receive packets.
6. Check ESXi for dropped transmit packets.

Question 7

What are the ways to export a log bundle?

Answer 7

vCenter Web Client
vCenter via vSphere client
Run vc-support.wsf from program files
Run /usr/sbin/vm-support from host’s ESXi CLI