Re: dhclient cause up/down cycle after 239356 ?

On Wednesday, August 22, 2012 9:35:34 pm Peter Jeremy wrote:
> On 2012-Aug-22 15:35:01 -0400, John Baldwin <jhb_at_freebsd.org> wrote:
> >Hmm.  Perhaps we could use a debouncer to ignore "short" link flaps?  Kind of
> >gross (and OpenBSD doesn't do this).  For now this change basically ignores
> >link up events if they occur with 5 seconds of the link down event.  The 5 is
> >hardcoded which is kind of yuck.
> 
> I'm also a bit concerned about this for similar reasons to adrian_at_.
> We need to distinguish between short link outages caused by (eg) a
> switch admin reconfiguring the switch (which needs the lease to be
> re-checked) and those caused by broken NICs which report link status
> changes when they are touched.  Maybe an alternative is to just ignore
> link flaps when they occur within a few seconds of a script_go().
> (And/or make the ignore timeout configurable).
> 
> Apart from fxp(4), does anyone know how many NICs are similarly
> broken?
> 
> Does anyone know why this issue doesn't bite OpenBSD?  Does it have
> a work-around to avoid resetting the link, not report link status
> changes or just no-one has noticed the issue?

To be clear, I don't like this hack.  If there is a way to fix this in
the driver (e.g. not report the link state changes during a reset) that
would be far preferable.

-- 
John Baldwin