Specifying the source IP address for outgoing RADIUS packets

About source IP address for outgoing RADIUS packets

The source IP address of RADIUS packets that a NAS sends must match the IP address of the NAS configured on the RADIUS server. A RADIUS server identifies a NAS by its IP address. Upon receiving a RADIUS packet, a RADIUS server checks whether the source IP address of the packet is the IP address of a managed NAS.

Before sending a RADIUS packet, the NAS selects a source IP address in the following order:

  1. The source IP address specified for the RADIUS scheme.

  2. The source IP address specified in system view for the VPN or public network, depending on where the RADIUS server resides.

  3. The IP address of the outbound interface specified by the route.

Restrictions and guidelines for source IP address configuration

You can specify a source IP address for outgoing RADIUS packets in RADIUS scheme view or in system view.

The source IP address of RADIUS packets that a NAS sends must match the IP address of the NAS that is configured on the RADIUS server.

As a best practice, specify a loopback interface address as the source IP address for outgoing RADIUS packets to avoid RADIUS packet loss caused by physical port errors.

The source address of outgoing RADIUS packets is typically the IP address of an egress interface on the NAS to communicate with the RADIUS server. However, in some situations, you must change the source IP address. For example, when VRRP is configured for stateful failover, configure the virtual IP of the uplink VRRP group as the source address.

Specifying a source IP address for all RADIUS schemes

  1. Enter system view.

    system-view

  2. Specify a source IP address for outgoing RADIUS packets.

    radius nas-ip { ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]

    By default, the primary IP address of the RADIUS packet outbound interface is used as the source IP address.

Specifying a source IP address for a RADIUS scheme

  1. Enter system view.

    system-view

  2. Enter RADIUS scheme view.

    radius scheme radius-scheme-name

  3. Specify a source IP address for outgoing RADIUS packets.

    nas-ip { ipv4-address | ipv6 ipv6-address }

    By default, the source IP address specified by using the radius nas-ip command in system view is used. If the source IP address is not specified, the primary IP address of the outbound interface is used.