Static Addressing

Learn how to configure static addresses and routes on the link.

Static addressing allows you to assign fixed IP addresses to network interfaces in Talos Linux. Static configuration is available for physical and logical links (bridges, bonds, VLANs). For physical links, configuration is attached to the LinkConfig document, while for logical links, configuration is attached directly to the logical link document.

Configuration

Addresses can be specified in the addresses field as a list of CIDR (Classless Inter-Domain Routing) notation strings:

addresses:
    - address: 192.168.1.100/24
    - address: 2001:db8::1/64
      routePriority: 100

The routePriority field is optional and can be used to set the priority of the implicit route associated with the address.

Routes can be specified in the routes field as a list of route objects:

routes:
    - destination: 10.3.5.0/24
      gateway: 10.3.5.1
    - gateway: fe80::1

Each route object can include the following fields:

• destination: The destination network in CIDR notation. If omitted, a default route is created.
• gateway: The gateway IP address for the route. If omitted, the route is considered directly connected.
• additional advanced fields like metric, mtu can be specified as needed.

There are some typical configuration scenarios to consider:

• address with a subnet and a default route via the gateway from the same subnet:

  addresses:
      - address: 192.168.1.100/24
  routes:
      - gateway: 192.168.1.1
  

  With this configuration, all addresses 192.168.1.1-192.168.1.254 are reachable directly, while all other addresses are reachable via the gateway 192.168.1.1.

• a machine is given an address from a subnet, but the default gateway is outside of that subnet:

  addresses:
      - address: 192.168.1.100/32
  routes:
      - destination: 192.168.1.1
      - gateway: 192.168.1.1
  

  In this example, the machine has a /32 address, so no other addresses are reachable directly. A specific route to the gateway 192.168.1.1 is required to reach other networks.

• a private network which doesn’t have a default gateway, but needs specific routes to other networks:

  addresses:
      - address: 10.0.0.3/24
  routes:
      - destination: 10.1.0.0/24
        gateway: 10.0.0.1
  

A complete example of static addressing configuration for a physical link:

apiVersion: v1alpha1
kind: LinkConfig
name: enp0s3
addresses:
    - address: 192.168.1.100/24
routes:
    - gateway: 192.168.1.1

Observing status

You can observe the status of addresses and routes using talosctl:

$ talosctl get addresses
NODE         NAMESPACE   TYPE            ID                                    VERSION   ADDRESS                        LINK
172.20.0.2   network     AddressStatus   enp0s2/172.20.0.2/24                  1         172.20.0.2/24                  enp0s2
172.20.0.2   network     AddressStatus   enp0s2/fe80::ac48:3dff:feca:3828/64   2         fe80::ac48:3dff:feca:3828/64   enp0s2
172.20.0.2   network     AddressStatus   lo/127.0.0.1/8                        1         127.0.0.1/8                    lo
172.20.0.2   network     AddressStatus   lo/169.254.116.108/32                 1         169.254.116.108/32             lo
172.20.0.2   network     AddressStatus   lo/::1/128                            1         ::1/128                        lo

And same for routes:

NODE         NAMESPACE   TYPE          ID                                                    VERSION   DESTINATION                     GATEWAY      LINK     METRIC
172.20.0.2   network     RouteStatus   enp0s2/inet6//fe80::/64/256                           1         fe80::/64                                    enp0s2   256
172.20.0.2   network     RouteStatus   inet4//172.20.0.0/24/1024                             1         172.20.0.0/24                                enp0s2   1024
172.20.0.2   network     RouteStatus   inet4/172.20.0.1//1024                                1                                         172.20.0.1   enp0s2   1024
172.20.0.2   network     RouteStatus   local/enp0s2/inet6//fe80::/128/0                      1         fe80::/128                                   enp0s2   0
172.20.0.2   network     RouteStatus   local/enp0s2/inet6//fe80::ac48:3dff:feca:3828/128/0   1         fe80::ac48:3dff:feca:3828/128                enp0s2   0
172.20.0.2   network     RouteStatus   local/enp0s2/inet6//ff00::/8/256                      1         ff00::/8                                     enp0s2   256
172.20.0.2   network     RouteStatus   local/inet4//127.0.0.0/8/0                            1         127.0.0.0/8                                  lo       0
172.20.0.2   network     RouteStatus   local/inet4//127.0.0.1/32/0                           1         127.0.0.1/32                                 lo       0
172.20.0.2   network     RouteStatus   local/inet4//127.255.255.255/32/0                     1         127.255.255.255/32                           lo       0
172.20.0.2   network     RouteStatus   local/inet4//169.254.116.108/32/0                     1         169.254.116.108/32                           lo       0
172.20.0.2   network     RouteStatus   local/inet4//172.20.0.2/32/0                          1         172.20.0.2/32                                enp0s2   0
172.20.0.2   network     RouteStatus   local/inet4//172.20.0.255/32/0                        1         172.20.0.255/32                              enp0s2   0
172.20.0.2   network     RouteStatus   local/lo/inet6//::1/128/0                             1         ::1/128                                      lo       0

This shows all configured addresses and routes, including those automatically created for link-local addresses, managed by CNI plugins, or other system components.

To see the list of addresses and routes managed by Talos, use the following:

$ talosctl get addressspecs
NODE         NAMESPACE   TYPE          ID                      VERSION
172.20.0.2   network     AddressSpec   enp0s2/172.20.0.2/24    2
172.20.0.2   network     AddressSpec   lo/127.0.0.1/8          2
172.20.0.2   network     AddressSpec   lo/169.254.116.108/32   2
$ talosctl get routespecs
NODE         NAMESPACE   TYPE        ID                       VERSION
172.20.0.2   network     RouteSpec   inet4/172.20.0.1//1024   2

In order to see managed configuration with information about various sources (static config, DHCP, CNI, etc.) add --namespace=networkconfig flag:

$ talosctl get addressspecs --namespace network-config
NODE         NAMESPACE        TYPE          ID                                  VERSION
172.20.0.2   network-config   AddressSpec   default/lo/127.0.0.1/8              1
172.20.0.2   network-config   AddressSpec   dhcp4/enp0s2/enp0s2/172.20.0.2/24   1
172.20.0.2   network-config   AddressSpec   operator/lo/169.254.116.108/32      1
$ talosctl get routespecs --namespace network-config
NODE         NAMESPACE        TYPE        ID                                    VERSION
172.20.0.2   network-config   RouteSpec   dhcp4/enp0s2/inet4/172.20.0.1//1024   1