Interfaces

Interface Addresses

Each interface can be configured with a description and address. Interface addresses might be:

  • Static IPv4 address 172.16.51.129/24

  • Static IPv6 address 2001:db8:1::ffff/64

  • DHCP IPv4 address dhcp

  • DHCP IPv6 address dhcpv6

An interface description is assigned using the following command:

set interfaces ethernet eth0 description 'OUTSIDE'

IPv4

Static Address

This method is supported on all interfaces, apart from OpenVPN that uses different syntax and wireless modems that are always autoconfigured through PPP.

The command is set interfaces $type $name address $address. Examples:

set interfaces ethernet eth0 address 192.0.2.1/24
set interfaces tunnel tun0 address 10.0.0.1/30
set interfaces bridge br0 address 203.0.113.45/26
set interfaces ethernet eth0 vif 30 address 192.0.30.254/24

DHCP

This method is supported on all physical interfaces, and those that are directly connected to a physical interface (ethernet, VLAN, bridge, bond, pseudo-ethernet, wireless).

The command is set interfaces $type $name address dhcp. Examples:

set interfaces ethernet eth0 vif 90 address dhcp
set interfaces bridge br0 address dhcp

IPv6

Static Address

This method is supported on all interfaces, apart from OpenVPN that uses different syntax and wireless modems that are always autoconfigured through PPP. Static IPv6 addresses are supported on all interfaces except Tunnel Interfaces.

The command is set interfaces $type $name address $address. Examples:

set interfaces ethernet eth0 address 2001:db8:100::ffff/64
set interfaces tunnel tun0 address 2001:db8::1/64
set interfaces bridge br0 address  2001:db8:200::1/64
set interfaces ethernet eth0 vif 30 address 2001:db8:3::ffff/64

DHCP

This method is supported on all physical interfaces, and those that are directly connected to a physical interface (ethernet, VLAN, bridge, bond, pseudo-ethernet, wireless).

The command is set interfaces $type $name address dhcpv6. Examples:

set interfaces bonding bond1 address dhcpv6
set interfaces bridge br0 vif 56 address dhcpv6

Autoconfiguration (SLAAC)

SLAAC is specified in RFC4862. This method is supported on all physical interfaces, and those that are directly connected to a physical interface (ethernet, VLAN, bridge, bond, pseudo-ethernet, wireless).

The command is set interfaces $type $name ipv6 address autoconf. Examples:

set interfaces ethernet eth0 vif 90 ipv6 address autoconf
set interfaces bridge br0 ipv6 address autoconf

Note

This method automatically disables IPv6 traffic forwarding on the interface in question.

EUI-64

EUI-64 (64-Bit Extended Unique Identifier) as specified in RFC4291. IPv6 addresses in /64 networks can be automatically generated from the prefix and MAC address, if you specify the prefix.

The command is set interfaces $type $name ipv6 address eui64 $prefix. Examples:

set interfaces bridge br0 ipv6 address eui64 2001:db8:beef::/64
set interfaces pseudo-ethernet peth0 ipv6 address eui64 2001:db8:aa::/64

Router Advertisements

Router advertisements are described in RFC4861 section 4.2. They are part of what is known as SLAAC (Stateless Address Autoconfiguration).

To enable or disable, use:

set interfaces <interface> ipv6 router-advert send-advert <true or false>

To set the options described in “Router Advertisement Message Format”:

vyos@vyos#  set interfaces <interface> ipv6 router-advert
Possible completions:
  cur-hop-limit         Value to be placed in the "Current Hop Limit" field in RAs
  default-lifetime      Value to be placed in "Router Lifetime" field in RAs
  default-preference    Default router preference
  link-mtu              Value of link MTU to place in RAs
  managed-flag          Value for "managed address configuration" flag in RAs
  max-interval          Maximum interval between unsolicited multicast RAs
  min-interval          Minimum interval between unsolicited multicast RAs
+  name-server          IPv6 address of a Recursive DNS Server
  other-config-flag     Value to be placed in the "other configuration" flag in RAs
+> prefix               IPv6 prefix to be advertised in Router Advertisements (RAs)
  reachable-time        Value to be placed in "Reachable Time" field in RAs
  retrans-timer         Value to place in "Retrans Timer" field in RAs.
  send-advert           Enable/disable sending RAs

Prefix Information

Prefix information is described in RFC4861 section 4.6.2

vyos@vyos# set interfaces <interface> ipv6 router-advert prefix <h:h:h:h:h:h:h:h/x>
Possible completions:
  autonomous-flag       Whether prefix can be used for address auto-configuration
  on-link-flag          Flag that prefix can be used for on-link determination
  preferred-lifetime    Time in seconds that the prefix will remain preferred
  valid-lifetime        Time in seconds that the prefix will remain valid

Receiving Router Advertisements

To receive and accept RAs on an interface, you need to enable it with the following configuration command

vyos@vyos# set system sysctl custom net.ipv6.conf.<interface name>.accept_ra value 2