"Route based on physical NIC load" policy does not work as expected

Products

• VMware vSphere ESXi
• VMware vSphere ESX 8.x

Issue/Introduction

• 'Route based on physical NIC load' loadbalancing policy does not work as expected on the ESXi with multiple uplinks
• Issue is observed in VMware ESXi 8.X version
• The traffic exceeds 75% of vmnic's capacity. However, the load balancing doesn't occur
• If we run net-lbt -v from the ESXi host manually, it reports the vmnic is saturated and the NIC failover works

Environment

VMware vSphere ESX 8.x

Cause

The 'net-lbt' daemon doesn't function when run as a daemon until it is manually invoked by running the net-lbt -v command from the ESXi host. 

Resolution

VMware ESXi engineering team is aware of this issue, and it will be fixed in the future ESXi release. 

Workaround:

To workaround the issue, disable the security policy enforcement for netlbtDom by running the below command.
esxcli system secpolicy domain set -l disabled -n netlbtDom

Confirm the policy enforcement for netlbtDom is disabled by running the below command:

[root@esx-01:~] esxcli system secpolicy domain list | grep netlbtDom
netlbtDom                  enforcing

Note: Apply the workaround on all the ESXi hosts using 'Routing based on PNIC load':

Once the fix is released and the ESXi host is upgraded to that version, run the below command on all the ESXi hosts where the above workaround is applied. 
esxcli system secpolicy domain set -l enforcing -n netlbtDom

Confirm the netlbtDom is set to enforcing by running the below command. 

[root@esx-01:~] esxcli system secpolicy domain list | grep netlbtDom
netlbtDom                  enforcing