ufw.enable's soft_fail argument defaults to False

[Stuart Bishop]

The rare case is for charms to absolutely require ipv6 networking, so the default should be True (warn but continue if ipv6 is broken). Having the default aborting if ipv6 is broken means charms will fail needlessly if they don't require ipv6 and are run in a new environment where ipv6 happens to be broken. I can't really see downsides to changing the default - if ipv6 actually is required and ufw.enable doesn't abort, then something else will surely fail later.

[Felipe Reyes (freyes)]

Hi Stuart,

This is a bit tricky, because if we set the default to True we could be leaving services silently exposed over IPv6. Considering this I tried to avoid a big security risk and users (deployers or charm authors) have to opt-in to soft-fail.

If a given charm doesn't mind this, then the author can simple use soft_fail=True. I think this is a fair balance between security and usability of our library.

Best,

[Stuart Bishop (stub)]

@freyes I don't follow your logic. The default now is to abort if IPv6 is broken. I suggest ignoring the problem if IPv6 is broken. The behavior if IPv6 is working is the same, so the risk of leaving services silently exposed over IPv6 is the same (you can't expose a service over a broken protocol).

(But I'm not too worried, as my understanding is that Juju will grow features that I think make this module obsolete)