Host Interfaces

Host interfaces are interfaces which have not been allocated to the dataplane. As such, these exist separate from other types of TNSR interfaces. As the name implies, they are available for use by the host operating system. These interfaces are primarily used for host OS management.

Host interfaces may be managed from TNSR as described in this section, or using another mechanism in the host OS, such as Netplan.


TNSR automatically imports host OS interface configuration settings from the installer or cloud deployment mechanisms. This allows TNSR to manage these pre-defined host interfaces.

Administrators can still manage host OS interfaces manually. To prevent TNSR from importing or altering manual host OS network settings, the settings must not be placed in common filenames used by the installer or cloud provider deployment mechanisms.


To be used as a host interface, an interface must not be used by the dataplane. To return an interface from dataplane to host control, see Remove TNSR NIC for Host Use.

Host Interface Configuration

To configure a host interface, from config mode, use the host interface <name> command to enter config-host-if mode. The <name> parameter is the name of the interface in the host operating system. To see a list of available interfaces, use show host interface.

config-host-if mode contains the following commands:

description <text>

A brief text description of this interface, such as Management.


Enables or disables the interface.

ip address <ipv4-prefix>

Sets a static IPv4 address and CIDR mask to use on the interface.

ip dhcp-client (enable|disable)

Enable or disable the IPv4 DHCP client for this interface to obtain an IPv4 address automatically.

This will also obtain and use a default route for the host namespace if one is supplied by the DHCP server.

ip dhcp-client hostname <name>

Set the hostname used by the DHCP client when requesting a lease from a DHCP server.

ipv6 address <ipv6-prefix>

Sets a static IPv6 address and prefix to use on the interface.

ipv6 dhcp-client (enable|disable)

Enable or disable the IPv6 DHCP client for this interface to obtain an IPv6 address automatically.


The host OS will not start a DHCPv6 client unless the OS observes a router advertisement on that interface with a “managed” or “other configuration” flag set. For this feature to work properly, ensure there is a working IPv6 router on the network segment attached to the host OS interface.

mtu <mtu-value>

Sets the maximum transmission unit size for the interface.

Host Interface Example

This example configures the host OS interface enp8s0f1 with an IP address of and an MTU of 1500:

tnsr# configure
tnsr(config)# host int enp8s0f1
tnsr(config-host-if)# ip address
tnsr(config-host-if)# mtu 1500
tnsr(config-host-if)# enable
tnsr(config-host-if)# exit
tnsr(config)# exit

To confirm that the settings were applied to the interface, use show host interface:

tnsr# show host interface enp8s0f1
Interface: enp8s0f1
    Link up
    Link MTU: 1500 bytes
    MAC address: 00:90:0b:7a:8a:6a
    IPv4 addresses:

As additional confirmation, check how the interface looks in the host operating system using a shell command:

tnsr# host shell ip addr show enp8s0f1
7: enp8s0f1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 00:90:0b:7a:8a:6a brd ff:ff:ff:ff:ff:ff
    inet scope global enp8s0f1
       valid_lft forever preferred_lft forever

Host Interface Status

The show host interface (<name>|ipv4|ipv6|link) command shows the current status of host interfaces. When run without parameters, show host interface will print the status of all host interfaces.

The command also supports the following parameters:


The name of an interface. Restricts the output to only the single given interface.


Restricts the output to include only interface IPv4 addresses.


Restricts the output to include only interface IPv6 addresses.


Restricts the output to include only interface link status information, including the MTU and MAC address.

Any subset of these parameters may be given in the same command to include the desired information.