Configure TWAMP

With the exception of physical interfaces, TWAMP server configuration for Junos OS requires the following minimum configuration at the [edit services rpm twamp] hierarchy level:

server {
    authentication-mode mode;
    client-list list-name {
        address ip-address;
    }
    port 862;
}

Starting in Junos OS Release 21.3R1, you no longer need to configure the authentication-mode statement. The default mode is now none, which means that communications with the server are not authenticated.

• To specify the list of allowed control client hosts that can connect to this server, include the client-list statement at the [edit services rpm twamp server] hierarchy level. Each value you include must be a Classless Interdomain Routing (CIDR) address (IP address plus mask) that represents a network of allowed hosts. You can include multiple client lists, each of which can contain a maximum of 64 entries. You must configure at least one client address to enable TWAMP.

• ACX Series routers do not support authentication and encryption modes. The value for authentication-mode statement at the [edit services rpm twamp server] hierarchy level must be set to none.

• TWAMP control connection traffic always arrives on ACX routers with the listening port set as 862. Because this port number for traffic probes can be modified, probes that arrive with a different port number are not recognized and processed by ACX routers correctly. As a result, TWAMP traffic and host-bound packets are dropped in such a scenario.

Configure TWAMP provides information about support for light control of the server.

For Junos OS, you can configure light control for the server (managed control is the default). The Junos OS TWAMP server configuration for light control requires the following minimum configuration at the [edit services rpm twamp] hierarchy level:

server {
   authentication-mode none;
   light;
   port (862 | 878 | 51000);
}

For Junos OS, for a list of restrictions on source addresses, see source-address (TWAMP).

For Junos OS Evolved, you can configure either managed or light control for the server. TWAMP server configuration for managed or light control requires the following minimum configuration at the [edit services monitoring twamp] hierarchy level, assuming you use the default port for TWAMP (862):

server {
    (managed | light);
}

For Junos OS Evolved, you cannot use the following addresses for the client-list source IP address used for probes:

• 0.0.0.0

• 127.0.0.0/8 (loopback)

• 224.0.0.0/4 (multicast)

• 255.255.255.255 (broadcast)

You can configure more than one client, and you can change the TWAMP listening port as long as the change is coordinated with the TWAMP client.

For microkernel-based timestamping in Junos OS, you don’t need to configure an si- interface. In this case, the TWAMP connection and sessions are established based on the target address and route.

For inline timestamping in Junos OS, you need to configure si- or sp- services interfaces and theTWAMP server configuration requires the following statements at the [edit interfaces service-interface-name] hierarchy level:

user@router# show interfaces si-0/0/0
unit 10 {
    rpm twamp-server;
    family inet {
        address 10.10.10.1/24;
    }
}

user@router# show interfaces sp-0/0/0
unit 10 {
    rpm twamp-server;
    family inet {
        address 10.20.20.1/24;
    }
}

(Junos OS only) To configure a TWAMP server on an inline services (si-) interface, configure the amount of bandwidth reserved on each Packet Forwarding Engine for tunnel traffic using inline services by including the bandwidth (1g | 10g) statement at the [edit chassis fpc slot-number pic number inline-services] hierarchy level. Specify the service PIC (sp-) logical interface that provides the TWAMP service by including the twamp-server statement at the [edit interfaces sp-fpc/pic/port unit logical-unit-number family inet] hierarchy level.

The twamp-server statement is not required for physical interface TWAMP server configuration.

Many other TWAMP server parameters are optional. See the TWAMP server configuration statements for details.

For Junos OS, to configure the TWAMP client service, include the client statement and related parameters at the [edit services rpm twamp] hierarchy level. For Junos OS Evolved, include the client statement and related options at the [edit services monitoring twamp] hierarchy level.

There are many options available for TWAMP client configuration. See the configuration statement topics and examples for details.

For microkernel-based timestamping in Junos OS, you don’t need to configure an si- interface. In this case, the TWAMP connection and sessions are established based on the target address and route.

For inline timestamping in Junos OS, the si- interfaces are virtual physical interfaces that respond as a TWAMP server. However, you can also configure services interfaces to act as the TWAMP client, which performs the TWAMP controller role.

(Junos OS only) To configure a services interface as a TWAMP client, you configure the service parameters and the service interface as a TWAMP client.

To configure the TWAMP client services interface, include the rpm twamp-client statement at the [edit interfaces si-interface-name] hierarchy level:

user@router# show interfaces si-0/0/0
unit 0 {
    family inet;
}
unit 10 {
    rpm twamp-client;
    family inet {
        address 10.30.30.1/24
    }
}