The following configuration throws the above error:
```
ethernet eth2 {
duplex auto
hw-id 00:0d:b9:53:07:ee
smp-affinity auto
speed auto
+ vif 7 {
+ pppoe 0 {
+ default-route force
+ mtu 1300
+ name-server auto
+ password 123456789
+ user-id vyos@vyos.io
+ }
+ }
}
```
Reproduce by:
```
set interfaces ethernet eth2 vif 7 pppoe 0 default-route 'force'
set interfaces ethernet eth2 vif 7 pppoe 0 link 'eth2'
set interfaces ethernet eth2 vif 7 pppoe 0 mtu '1300'
set interfaces ethernet eth2 vif 7 pppoe 0 name-server 'auto'
set interfaces ethernet eth2 vif 7 pppoe 0 password '123456789'
set interfaces ethernet eth2 vif 7 pppoe 0 user-id 'vyos@vyos.io'
```