Mobility Network Health Check feature

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

Mobility Network Health Check is a standalone script that checks the vMotion network health on an ESXi host with a cluster membership list.

• This feature allows admins to check the mobility network for config and connectivity issues proactively.
• These checks are also run during support bundle collection.

Environment

This script is available by default on ESXi hosts that are 8.0 U3 or higher. 

Cause

vMotion might fail because of network configuration and/or connectivity issues. 

Resolution

The health check script can validate vMotion and provisioning networks for config and connectivity issues.

Script Steps

1. Collect local network config
2. Validate local network config
   
   • Validate that vMotion and provisioning networks are properly defined. i.e. vMotion and/or network stacks are defined or there are vmknics tagged for vMotion and/or provisioning
   • Verify that these vmknics are connected to physical nics that have network connectivity (link up).
   • Verify that MTU is consistent through vmknic -> vSwitch -> physical nic
   • Analyze vmknic stats to check if any packet loss was reported
3. Check network connectivity

• • Checks that TCP connection can be established to specified IP over vMotion or provisioning network to vMotion (8000) or provisioning (902) port.
  • Ping specified IP over vMotion or provisioning network using packet size with vmknic MTU. Checks for RTT and packet loss.  

Script Output

The script output is in json format and contains information for all checks that were invoked with the checks result. 

Example Script Commands

Below are a few examples for script commands.

Print help:

python -m vmware.mobility.mobility_health_checks -h

Print local network config:

python -m vmware.mobility.mobility_health_checks --dump-net-config

Check local vMotion and provisioning networks config (default):

python -m vmware.mobility.mobility_health_checks

To check config for one of the networks:

python -m vmware.mobility.mobility_health_checks --provisioning

python -m vmware.mobility.mobility_health_checks --vmotion

To check connectivity to a specific IP using a specified network:

python -m vmware.mobility.mobility_health_checks --vmotion 10.170.97.5

Optionally, add the following to run the above commands without config check:  --no-config-check argument

Check for Intra-Cluster Connectivity and Mobility Network Memberships

If the host is a member of a cluster, run the below command to check for intra-cluster connectivity (i.e. connectivity to all hosts in the cluster). This check runs by default during support bundle collection.

python -m vmware.mobility.mobility_health_checks --cluster-connectivity-check

To see mobility network membership (i.e. the list of all IP addresses used for intra-cluster connectivity checks)

/bin/configstorecli config current get -c esx -g health -k mobility_network_membership

Note: This list is pushed by vCenter every 12 hours (configurable) to all hosts in the cluster.