Virtual Ethernet
The veth devices are virtual Ethernet devices. They can act as tunnels between network namespaces to create a bridge to a physical network device in another namespace or VRF, but can also be used as standalone network devices.
Note
veth interfaces need to be created in pairs - it’s called the peer name
Configuration
Common interface configuration
Configure interface <interface> with one or more interface addresses.
address can be specified multiple times as IPv4 and/or IPv6 address, e.g. 192.0.2.1/24 and/or 2001:db8::1/64
dhcp interface address is received by DHCP from a DHCP server on this segment.
dhcpv6 interface address is received by DHCPv6 from a DHCPv6 server on this segment.
Note
When using DHCP to retrieve IPv4 address and if local customizations are needed, they should be possible using the enter and exit hooks provided. The hook dirs are:
/config/scripts/dhcp-client/pre-hooks.d//config/scripts/dhcp-client/post-hooks.d/
Example:
set interfaces virtual-ethernet veth0 address 192.0.2.1/24
set interfaces virtual-ethernet veth0 address 2001:db8::1/64
set interfaces virtual-ethernet veth0 address dhcp
set interfaces virtual-ethernet veth0 address dhcpv6
Set a human readable, descriptive alias for this connection. Alias is used by
e.g. the show interfaces command or SNMP based monitoring tools.
Example:
set interfaces virtual-ethernet veth0 description 'This is an awesome interface running on VyOS'
Disable given <interface>. It will be placed in administratively down
(A/D) state.
Example:
set interfaces virtual-ethernet veth0 disable
Place interface in given VRF instance.
See also
There is an entire chapter about how to configure a VRF, please check this for additional information.
Example:
set interfaces virtual-ethernet veth0 vrf red
Operation
Show brief interface information.
[email protected]:~$ show interfaces virtual-ethernet
Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
Interface IP Address S/L Description
--------- ---------- --- -----------
veth10 100.64.0.0/31 u/u
veth11 100.64.0.1/31 u/u
Show detailed information on given <interface>
[email protected]:~$ show interfaces virtual-ethernet veth11
10: [email protected]: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master red state UP group default qlen 1000
link/ether b2:7b:df:47:e9:11 brd ff:ff:ff:ff:ff:ff
inet 100.64.0.1/31 scope global veth11
valid_lft forever preferred_lft forever
inet6 fe80::b07b:dfff:fe47:e911/64 scope link
valid_lft forever preferred_lft forever
RX: bytes packets errors dropped overrun mcast
0 0 0 0 0 0
TX: bytes packets errors dropped carrier collisions
1369707 4267 0 0 0 0
Example
Interconnect the global VRF with vrf “red” using the veth10 <-> veth 11 pair
set interfaces virtual-ethernet veth10 address '100.64.0.0/31'
set interfaces virtual-ethernet veth10 peer-name 'veth11'
set interfaces virtual-ethernet veth11 address '100.64.0.1/31'
set interfaces virtual-ethernet veth11 peer-name 'veth10'
set interfaces virtual-ethernet veth11 vrf 'red'
set vrf name red table '1000'
[email protected]:~$ ping 100.64.0.1
PING 100.64.0.1 (100.64.0.1) 56(84) bytes of data.
64 bytes from 100.64.0.1: icmp_seq=1 ttl=64 time=0.080 ms
64 bytes from 100.64.0.1: icmp_seq=2 ttl=64 time=0.119 ms