Bug #15452
open
Unexpected/Undefined behaviour of disabled interfaces
0%
Description
Interfaces that are assigned but disabled can produce unexpected behaviour.
Setting an interface to disabled when it was previously enabled will set the interface as down or remove it entirely for sub-interface types.
That happens even if other interfaces are using it as a parent creating unexpected failures such as:
https://redmine.pfsense.org/issues/9453
However an interface assigned but disabled will still be brought up or created at boot.
More confusing is that parameters set on the disabled interface will still be set on it at boot.
Some users are using that behaviour to set parameters such as the MTU on a VLAN parent which works but brings down all the sub-interfaces until reboot.
There is no input error checking to prevent it.
My own understanding here is that an interface should be assigned an d enabled in order to apply config to it but the expected behaviour seems to be undefined.
We looked at this before here: https://redmine.pfsense.org/issues/11091
Nothing ended up from that after hitting more problems than it solved.
- Interface config should not be applied to disabled interfaces at any time. Any users using this behaviour will need to enable those interfaces.
- Saving an interface config that is already disabled should not kill the interface. But it would need to apply new parameters.
Related issues
Updated by Steve Wheeler 17 days ago
The first option there seems far more logical to me but I have always assumed that was the behaviour anyway. Anyone relying on that behaviour might disagree!
Updated by
Updated by Marcos M 8 days ago
Some parent interfaces like LAGGs are configured separately from the assigned interfaces page. The undefined behavior is an issue once those parent interfaces are also assigned in the interfaces page since doing so introduces two sources of potentially conflicting configurations.
In the case of an assigned LAGG interface the "Enabled" field can be hidden since the existence of the LAGG configuration means it should be created, enabled, and configured. Otherwise disabling the interface results in it being created from the LAGG page then deleted from the assigned (and disabled) page. On upgrade, disabled LAGG interfaces would need to be enabled automatically.