VMware Cloud Director UI fails to load or shows "Unable to perform query" with an NSX-T Load Balancer

Products

• VMware Cloud Director

Issue/Introduction

• You may see "Unable to perform query" after logging in to the VCD UI.
• Browser developer tools show a 502 Gateway error on cloudapi requests.
• Bypassing the Load Balancer by adding the IP and FQDN to your local machines host file does not work.

Environment

VMware Cloud Director
NSX-T

Cause

• NSX-T Load Balancer profile settings are using default or insufficient values for Request/Response Header size and timeouts.
• This prevents larger payloads from passing through the Load Balancer.

Resolution

Update the HTTP/HTTPS Load Balancer profile under: Networking > Load Balancing > Profiles > HTTP & HTTP

Use the following configuration:

• Type: HTTPS
• HTTP Request Header: X-Forward-For
• Idle Timeout: 15 Seconds
• Response Timeout: 60 Seconds
• Request Header Size: 65535
• Response Header Size: 50000

These details are outlined in the VMware Cloud Director Cell Load Balancing Configuration guide.

Additional Information

• To verify, inspect the network tab in browser developer tools. Refresh the VCD page and look for a failed request to cloudapi.
• If the load balancer is misconfigured, the request will fail with a 502 Gateway error.