VMware HCX [VMC on AWS] - Error "Failed to add HCX DX route for CIDR"

Products

• VMware HCX

Issue/Introduction

In a VMware Cloud (VMC) on AWS environment, the error "Failed to add HCX DX route for CIDR" may be seen in the HCX Cloud Manager UI under:

Interconnect - Network Profiles - directConnectNetwork1

Resolution

Ensure the IP address range (CIDR) configured for Network Profile directConnectNetwork1 does not overlap with the VMware Cloud (VMC) on AWS management subnet CIDR block or any other IP address range already in use for services in the VMC. Overlap can cause routing and network reachability issues for those other components. The CIDR used should be large enough so that each HCX Interconnect or Network Extension (IX/NE) appliance deployed at the VMC cloud site can be assigned an IP address. Also ensure the same CIDR is not used in the on-premise environment.

Existing Segment IP ranges used in the VMC can be checked from the VMware Cloud Console GUI by selecting:

Network & Security - Segments - Segment List

The CIDR used should only be configured in the directConnectNetwork1 Network Profile. It must not be configured as a network segment within the VMC SDDC. After creation in the directConnectNetwork1 Network Profile this new network will be advertised via BGP over the Direct Connect (DX) to the on-premise site. This can be checked from the VMware Cloud Console GUI by selecting:

Network & Security - Direct Connect