[Drbd-dev] drbdsetup events patch to announce Split-brain

[Montrose, Ernest]

Phil,
I think this will work for us actually. So feel free to check it in.

Thanks,

EM--
-----Original Message-----
From: Philipp Reisner [mailto:philipp.reisner at linbit.com] 
Sent: Monday, October 29, 2007 6:20 AM
To: Montrose, Ernest
Cc: drbd-dev at linbit.com
Subject: Re: [Drbd-dev] drbdsetup events patch to announce Split-brain

On Thursday 25 October 2007 14:24:55 Montrose, Ernest wrote:
> Phil,
> Currently we do not use the payload for anything.  I was just being
> paranoid thinking that we might need it in the future.  But you can
drop
> it if you wish.  If we have a pressing need for it in the future,
we'll
> deal with it then.
>

Ernest,

Over the weekend I realized that the split brain event is quite
similar to a number of events we already signal back to userspace.

The invocation of handlers is also visible through the "drbdsetup
events"
interface.

The attached patch creates an handler called "split-brain". If you
can live with that interface as well, I will commit that...

In the future I want to go this way:

  * Allow one to set the usermode_helper to the empty string. Then it 
    is still possible to get all events through the "drbdsetup events"
    interface.
  * The "outdate-peer" usermode_helper sends an exit code back
    to kernel space. This is not yet possible when one only uses
    the "drbdsetup events" interface. This should get fixed.

-Phil
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