[VMC on AWS] HCX Appliance fails to start some services due to DNS resolution failure

Products

• VMware HCX
• VMware Cloud on AWS

Issue/Introduction

HCX web interface becomes inaccessible, and when the App-Engine service is inspected via the VM console or SSH, the following errors are reported.

[FAILED] Failed to start App-Engine.
[FAILED] Failed to start Appliance Management
[FAILED] Failed to start WebEngine

Cause

When DNS resolving between HCX and the configured DNS server fails, the App-engine service, which is dependent on other services (appliance-management, web-engine), fails to start.
As a result, the HCX Appliance Management Interface cannot run and the services keep starting themselves.

Resolution

To resolve this issue, ensure the following:

• The HCX appliance has proper network connectivity to the configured DNS server.
• DNS requests are not blocked by firewalls, security policies, or network devices.
• The DNS server field in the OVF deployment wizard is populated with the correct IP address.
• The HCX appliance is connected to the appropriate virtual switch port group.
• Verify that the DNS server is reachable from the HCX appliance.

After confirming the above, restart the App-Engine service on the HCX appliance to apply the changes.