This issue is resolved in NSX-T 2.4.3 and NSX-T 2.5 (upgrade from those version won't be affected by this issue).
Workaround:
To workaround the issue, disable SNMP before the upgrade and re-enable it after the upgrade is completed using the following commands:
#esxcli system snmp set -e false
#esxcli system snmp set -e trueTo verify the SNMP status, the following command can be used:
#/etc/init.d/snmpd statusExpected output when SNMP is running:
snmpd is runningExpected output when SNMP is not running:
snmpd is not runningAlternatively, you can disable SNMP using the vSphere Web client:
Select and ESXi host > click the "Configure" tab > select "Security Profile" > in go to Service and select "Edit..." > find the SNMP service and stop it as shown in the screenshot below: