NSX V2T migration failed at translation stage with error: TypeError: object of type 'NoneType' has no len()

Products

• VMware NSX Networking

Issue/Introduction

Symptoms:

• You are migrating from NSX for vSphere to an NSX-T version below 3.2.1.
• The migration succeeded except the last stage, translation import configuration, which fails.
• Below error can be seen in the NSX-T manager log: /var/log/migration-coordinator/translation.log

{'category': 'Unexpected error', 'error': "Transport Zone failed with 'object of type 'NoneType' has no len()'"}
Traceback (most recent call last):
 File "main.py", line 158, in <module>
  main(sys.argv)
...
 File "/opt/vmware/migration-coordinator-tomcat/bin/v2t/config-migrator/plugins/tz_plugin.py", line 1873, in _merge_trunk_vlan_ranges
  if len(vlan_ranges) < 2:
TypeError: object of type 'NoneType' has no len()

Environment

VMware NSX-T Data Center
VMware NSX-T Data Center 3.x

Cause

There is an issue with the NSX for vSphere VTEP VLAN, where they are configure with trunk, but the migration coordinator was told to use a VLAN. Due to this, Transport zone plugin script will raise the error while translating the configurations due to the condition check of the TYPE-VLAN.

Resolution

This issue is resolved in NSX-T 3.2.1 available at VMware Customer Connect

Workaround:
As NSX-T 3.2.1 is now Generally available, it is advised to migrate to this or later version.
Please make sure and input correct data regarding VLANs on NSX for vSphere during the migration.

Additional Information

Impact/Risks:
Migration from NSX for vSphere to NSX-T fails at the translation stage.