Don't know whether this is specific to openvpn or not
```
vyos@vyos# delete interfaces openvpn vtun0 openvpn-option
[edit]
vyos@vyos# set interfaces openvpn vtun0 openvpn-option "tls-auth /config/auth/tls-auth.key 0"
[edit]
vyos@vyos# compare
No changes between working and active configurations
[edit]
vyos@vyos# exit
Cannot exit: configuration modified.
Use 'exit discard' to discard the changes and exit.
[edit]
vyos@vyos# save
Warning: you have uncommitted changes that will not be saved.
Saving configuration to '/config/config.boot'...
Done
[edit]
vyos@vyos# compare
No changes between working and active configurations
[edit]
vyos@vyos# commit
[edit]
vyos@vyos# save
Saving configuration to '/config/config.boot'...
Done
[edit]
```