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---
lastproofread: '2026-01-26'
---
(virtual-ethernet)=
# Virtual Ethernet
Virtual Ethernet (veth) interfaces are software-based interfaces that operate
in pairs, creating a tunnel between each other. Traffic transmitted into one
interface of the pair (e.g., `veth0`) is delivered directly to its peer
interface (e.g., `veth1`).
Veth interfaces are commonly used to connect network namespaces or VRFs, but
they can also function as standalone virtual network interfaces.
:::{note}
Veth interfaces must be created in pairs, where each interface acts
as the peer of the other.
:::
## Configuration
### Common interface configuration
```{cmdincludemd} /_include/interface-address-with-dhcp.txt
:var0: virtual-ethernet
:var1: veth0
```
```{cmdincludemd} /_include/interface-description.txt
:var0: virtual-ethernet
:var1: veth0
```
### VLAN
#### Regular VLANs (802.1q)
```{cmdincludemd} /_include/interface-vlan-8021q.txt
:var0: virtual-ethernet
:var1: veth0
```
#### 802.1ad (QinQ)
```{cmdincludemd} /_include/interface-vlan-8021ad.txt
:var0: virtual-ethernet
:var1: veth0
```
```{cmdincludemd} /_include/interface-disable.txt
:var0: virtual-ethernet
:var1: veth0
```
```{cmdincludemd} /_include/interface-vrf.txt
:var0: virtual-ethernet
:var1: veth0
```
## Operation
```{opcmd} show interfaces virtual-ethernet
Show brief interface information.
:::{code-block} none
vyos@vyos:~$ 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
:::
```
```{opcmd} show interfaces virtual-ethernet \<interface\>
Show detailed interface information.
:::{code-block} none
vyos@vyos:~$ show interfaces virtual-ethernet veth11
10: veth11@veth10: <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
The following example shows how to connect the global VRF to VRF ‘red ‘ using
the `veth10` and `veth11` veth pair.
```none
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'
vyos@vyos:~$ 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
```
|