How to allow more than 63 remote clients in OpenVPN in NG Firewall

Overview

OpenVPN creates a /30 subnet for each remote client, "reserving" 4 individual IP addresses for each remote connection. The default Address Pool setting for OpenVPN is a /24 subnet, meaning 252 available IP addresses. This means that by default, OpenVPN cannot accept more than 63 simultaneous remote client connections.

Increasing the OpenVPN address pool

In order to provide more available IP addresses, we must increase the size of the pool allotted to OpenVPN.

Go to Apps > OpenVPN > Server and locate the Address Pool attribute at the left-hand side.

Each 1-value decrease in the CIDR notator (the number after the slash) doubles the size of the pool, so thus:

• /23 is 510 usable addresses, or 127 remote clients
• /22 is 1,022 addresses, or 255 clients
• /21 is 2,046 addresses, or 511 clients

…and so forth.

You do not need to redeploy your client config files for this change to take effect.