NSX Edge Load Balancer service (nginx) fails to start after upgrade with FATAL error.

Products

• VMware NSX

Issue/Introduction

• Post upgrading NSX, the NSX Edge Load Balancer service (i.e. nginx) fails to start.
  
  
• In the Edge /var/log/syslog, we will see FATAL error similar to the below:
  
  nsx_edge_hostname NSX 13017 LOAD-BALANCER [nsx@6876 comp="nsx-edge" subcomp="lb" s2comp="lb" level="FATAL"] [xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx075e] unexpected """ [version: 22] in /config/vmware/edge/lb/etc/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx075e/nginx.conf:48

Environment

VMware NSX

Cause

The root cause is a parsing limitation in the Load Balancer Control Plane. The Control Plane does not correctly process double quotation marks (") within the Load Balancer monitor configuration.



Although this invalid configuration may have been applied prior to the upgrade, it likely failed silently without affecting the active data plane. The upgrade process triggers a forced full configuration reload, attempting to apply the stored settings. The parser fails on the double quotes, preventing the nginx service from initializing.

Resolution

For the nginx to successfully load the configuration, the character (") needs to be escaped. This change will be introduced in one of the upcoming releases of NSX.

For now, the workaround would be to either remove the header "host" or, replace (") will the allowed characters. Currently, only (") seems to be unsupported.