Support for different sized networks as IP block for NSX Provider Gateway - VMware Cloud Director

Products

• VMware Cloud Director

Issue/Introduction

This article provides guidance on the supported network sizes and CIDR configurations when using IP blocks for NSX Provider Gateways in VMware Cloud Director.

Environment

• VMware Cloud Director 10.x
• VMware NSX

Cause

Is a /23 network supported as an IP block for an NSX Provider Gateway in VMware Cloud Director to accommodate approximately 500 IP addresses?

Resolution

VMware Cloud Director supports various CIDR sizes for IP blocks depending on the underlying NSX configuration. For a Provider Gateway, a /23 network is supported as an IP block CIDR to provide the required 500+ IP addresses.

Consider the following limits and best practices:

• CIDR Limit: There is a recommended limit of 10 CIDRs or IP ranges per IP block. Exceeding this may cause performance issues or trigger alarms such as "IP Block CIDRS or IP Ranges Limit Exceeded."
• IP Spaces Transition: For VMware Cloud Director 10.6.x and higher, IP Blocks are deprecated in favor of IP Spaces. It is recommended to migrate to IP Spaces for more flexible IP management and route advertisement capabilities.

To configure or review IP blocks:

1. Navigate to Provider portal > Cloud Resources > Provider Gateways.
2. Select the relevant gateway and go to Configuration > Network Specification.

Additional Information

• Migrate a Provider Gateway to Using IP Spaces
• For further assistance, see Contact Support.