Interface Loopback

This feature manages Loopback interface configuration for router IDs, management, and other virtual interface purposes. Loopback interfaces are virtual logical interfaces that provide a stable, always-up reference point for network services including routing protocol router IDs, management access, and service endpoints that remain accessible regardless of physical interface states.

Diagram

Classes

iosxr

Name	Type	Constraint	Mandatory	Default Value
devices	List	devices	No
device_groups	List	device_groups	No
global	Class	global	No

devices (iosxr)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

device_groups (iosxr)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

global (iosxr)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

configuration (iosxr.devices)

Name	Type	Constraint	Mandatory	Default Value
interfaces	Class	interfaces	No

interfaces (iosxr.devices.configuration)

Name	Type	Constraint	Mandatory	Default Value
loopbacks	List	loopbacks	No

loopbacks (iosxr.devices.configuration.interfaces)

Name	Type	Constraint	Mandatory	Default Value
id	Any	Integer[min: 0] or String[Regex: ^[0-9][0-9]*$] or String[Regex: ^.*[\$\%]\{.*$]	Yes
interface_groups	List	String	No
bandwidth	Integer	min: 0, max: 9223372036854775807	No
dampening	Boolean	true, false	No
dampening_decay_half_life	Integer	min: 1, max: 45	No
dampening_reuse_threshold	Integer	min: 1, max: 20000	No
dampening_suppress_threshold	Integer	min: 1, max: 20000	No
dampening_max_suppress_time	Integer	min: 1, max: 255	No
description	String		No
ipv4	Class	ipv4	No
ipv6	Class	ipv6	No
load_interval	Integer		No
logging_events_link_status	Boolean	true, false	No
mtu	Integer	min: 64, max: 65535	No
shutdown	Boolean	true, false	No
vrf	String		No

ipv4 (iosxr.devices.configuration.interfaces.loopbacks)

Name	Type	Constraint	Mandatory	Default Value
address	IP		No
mask	IP		No
algorithm	Integer	min: 128, max: 255	No
forwarding_enable	Boolean	true, false	No
helper_addresses	List	helper_addresses	No
mask_reply	Boolean	true, false	No
mtu	Integer	min: 68, max: 65535	No
redirects	Boolean	true, false	No
route_tag	Integer	min: 1, max: 4294967295	No
secondaries	List	secondaries	No
tcp_mss_adjust	Boolean	true, false	No
ttl_propagate_disable	Boolean	true, false	No
unnumbered	String		No
verify_unicast_source_reachable_via_allow_default	Boolean	true, false	No
verify_unicast_source_reachable_via_allow_self_ping	Boolean	true, false	No
verify_unicast_source_reachable_via	Choice	any, rx	No

ipv6 (iosxr.devices.configuration.interfaces.loopbacks)

Name	Type	Constraint	Mandatory	Default Value
addresses	List	addresses	No
autoconfig	Boolean	true, false	No
enable	Boolean	true, false	No
eui64_addresses	List	eui64_addresses	No
link_local_address	IP		No
link_local_route_tag	Integer	min: 1, max: 4294967295	No
link_local_zone	String		No
mtu	Integer	min: 1280, max: 65535	No
nd_cache_limit	Integer	min: 0, max: 128000	No
nd_prefix_default_no_adv	Boolean	true, false	No
nd_prefix_default_no_autoconfig	Boolean	true, false	No
tcp_mss_adjust	Boolean	true, false	No
ttl_propagate_disable	Boolean	true, false	No
verify_unicast_source_reachable_via_allow_default	Boolean	true, false	No
verify_unicast_source_reachable_via_allow_self_ping	Boolean	true, false	No
verify_unicast_source_reachable_via	Choice	any, rx	No

helper_addresses (iosxr.devices.configuration.interfaces.loopbacks.ipv4)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
vrf	String		Yes

secondaries (iosxr.devices.configuration.interfaces.loopbacks.ipv4)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
mask	IP		Yes
algorithm	Integer	min: 128, max: 255	No
route_tag	Integer	min: 1, max: 4294967295	No

addresses (iosxr.devices.configuration.interfaces.loopbacks.ipv6)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
length	Integer	min: 0, max: 128	Yes
algorithm	Integer	min: 128, max: 255	No
route_tag	Integer	min: 1, max: 4294967295	No
zone	String		No

eui64_addresses (iosxr.devices.configuration.interfaces.loopbacks.ipv6)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
length	Integer	min: 0, max: 128	Yes
algorithm	Integer	min: 128, max: 255	No
route_tag	Integer	min: 1, max: 4294967295	No
zone	String		No

Examples

Example 1: Basic Loopback Interface

iosxr:
  devices:
    - name: router-1
      host: 10.10.10.1:57400
      configuration:
        hostname: router-1
        interfaces:
          loopbacks:
            - id: 0
              description: "Router ID"
              ipv4:
                address: 10.0.0.1
                mask: 255.255.255.255

Example 2: Loopback with IPv6

iosxr:
  devices:
    - name: router-1
      host: 10.10.10.1:57400
      configuration:
        hostname: router-1
        interfaces:
          loopbacks:
            - id: 1
              description: "Management Loopback"
              ipv4:
                address: 10.1.1.1
                mask: 255.255.255.255
              ipv6:
                enable: true
                addresses:
                  - address: 2001:db8::1
                    length: 128

Example 3: Multiple Loopbacks with VRF

iosxr:
  devices:
    - name: router-1
      host: 10.10.10.1:57400
      configuration:
        hostname: router-1
        interfaces:
          loopbacks:
            - id: 0
              description: "Global Router ID"
              ipv4:
                address: 10.0.0.1
                mask: 255.255.255.255
            - id: 100
              description: "VRF CUSTOMER_A Loopback"
              vrf: CUSTOMER_A
              ipv4:
                address: 10.100.0.1
                mask: 255.255.255.255
              ipv6:
                enable: true
                addresses:
                  - address: 2001:db8:100::1
                    length: 128
            - id: 200
              description: "VRF CUSTOMER_B Loopback"
              vrf: CUSTOMER_B
              ipv4:
                address: 10.200.0.1
                mask: 255.255.255.255