Script for automatic validation of networking communication between vCenter and ESXi hosts.

Products

• VMware vCenter Server 8.0

Issue/Introduction

The script attached to this KB will help you on validating the communication on the main ports required for the functionalities of vCenter on accessing the ESXi hosts.

This is helpful on identifying root cause for the issue of ESXi in "Not responding" state.

The script will assist on automatically search for possible points of attention on the network communication, it is recommended a deeper validation to be performed depending on the script findings and behavior of the issue.

 

Environment

vCenter Server Appliance 8.0.x

Cause

ESXi hosts can be on "Not responding" state when there are networking issues or firewall blocks (KB 344682 (Troubleshooting an ESXi host in a "not responding"/"disconnected" state)

vCenter vpxd service can crash or be unresponsive when hosts cannot be reached due to networking failures.

Resolution

To run the script

1. Download the checkNetwork.py file attached.
   
   
2. Upload the script to vCenter Server Appliance as per KB 403632 (How to upload or download files to or from vCenter and ESXi hosts) 
   
   
3. Run the script using the command accordingly:
   
   
   • For all hosts managed by vCenter:
     python checkNetwork.py
     
     
   • For a single host to be tested:
     python checkNetwork.py -i IP_ADDRESS_OF_THE_ESXi

Output samples

When everything is fine:

 

If a host totally unresponsive (i.e.: if ESXi is powered off, crashed (PSOD) or the required ports are blocked firewall):

Testing only the affected host:

 

If hostd service stopped or unresponsive on the ESXi or if port 902 UDP traffic is blocked by firewall:

 

 

Additional Information

The checkNetwork.py script doesn't perform changes to the environment.