NSX Upgrade PreCheck: Distributed Load Balancer Warning/Error in VCF 9.1

Products

• VMware NSX
• VMware Cloud Foundation

Issue/Introduction

• Prechecks for upgrading to VCF 9.1 from NSX 4.2/9.0 when Distributed Load Balancer is configured on NSX
• There are two type of Prechecks messages based on Severity (WARNING or ERROR).  
• NSX precheck WARNING messages includes the below:

Found data inconsistencies: There will be traffic disruptions or connection reset on distributed load balancer during NSX upgrade on ESX hosts. The following features cannot be configured for distributed load balancer in VCF 9.1: error log level, access log enabled, persistence profiles.
Found data inconsistencies: The following features cannot be configured for distributed load balancer in VCF 9.1: error log level, access log enabled, persistence profiles.
Found data inconsistencies: Unsupported features for distributed load balancer in VCF 9.1, e.g. error log level, access log, persistence profiles, are configured and will be reset after upgrade.
Found data inconsistencies: There will be traffic disruptions or connection reset on distributed load balancer during NSX upgrade on ESX hosts. The following features cannot be configured for distributed load balancer in VCF 9.1: error log level, access log enabled, persistence profiles.

• NSX precheck ERROR message includes the below:

Found data inconsistencies: Default distributed load balancer instance is not supported in VCF 9.1 release. Please update the distributed load balancer to attach to a group.

Environment

VMware NSX 9.1
VMware Cloud Foundation 9.1

Cause

This is an expected behavior during the VCF 9.1 upgrade pre-check for Distributed Load Balancer (DLB)

Resolution

1. For prechecks WARNING messages
   • No actions to be taken.
   • Acknowledged the warning and proceed ahead for the upgrade.

     2.  For prechecks ERROR messages

• • Update the distributed load balancer to attach to a group.
  • Re-run the precheck again

Note: During NSX upgrade on ESX hosts, the distributed load balancer will briefly interrupt traffic. Traffic will resume after the client re-initiates the connections
In the VCF 9.1 release, enabling the virtual server access log, changing the error log level, and configuring persistence profiles are not supported for the distributed load balancer.

The following table lists the upgrade precheck warnings and errors for the VCF 9.1 release, categorized by the DLB configurations of NSX 4.2 or VCF 9.0.

DLB exists?	DLB connectivity path (API)	DLB unsupported features configured	Precheck Warning/Error	Upgrade precheck Warning/Error Message	Comments
No	N/A	N/A	N/A	N/A	N/A
Yes	Path of an empty group or Null	No	WARNING	Found data inconsistencies: The following features cannot be configured for distributed load balancer in VCF 9.1: error log level, access log enabled, persistence profiles.	Acknowledge the warning and no extra action is needed. There is no traffic impact.
Yes	Path of an empty group or Null	Yes	WARNING	Found data inconsistencies: Unsupported features for distributed load balancer in VCF 9.1, e.g. error log level, access log, persistence profiles, are configured and will be reset after upgrade.	Acknowledge the warning and no extra action is needed. There is no traffic impact.
Yes	Path of a group with segment ports	No	WARNING	Found data inconsistencies: There will be traffic disruptions or connection reset on distributed load balancer during NSX upgrade on ESX hosts. The following features cannot be configured for distributed load balancer in VCF 9.1: error log level, access log enabled, persistence profiles.	Acknowledge the warning and no extra action is needed.
Yes	Path of a group with segment ports	Yes	WARNING	Found data inconsistencies: There will be traffic disruptions or connection reset on distributed load balancer during NSX upgrade on ESX hosts. Unsupported features for distributed load balancer in VCF 9.1, e.g. error log level, access log, persistence profiles, are configured and will be reset after upgrade.	Acknowledge the warning and no extra action is needed.
Yes	DLB connectivity path is set to "ALL"	N/A	ERROR	Found data inconsistencies: Default distributed load balancer instance is not supported in VCF 9.1 release. Please update the distributed load balancer to attach to a group.	Default distributed load balancer instance refers to a DLB configuration where the connectivity path in the API is set to "ALL". This configuration is no longer supported starting from VCF 9.1.