[libvirt] [PATCHv2 1/7] interface: new public API for networkconfig change transactions

[Daniel Veillard]

On Thu, May 19, 2011 at 05:15:20PM -0500, Christian Benvenuti (benve) wrote:
> > As a failsafe measure, if neither ncf_change_commit() or
> > ncf_change_rollback() is called by the next time the system reboots,
> > the netcf-transaction initscript will be automatically called to
> > rollback the changes.
> 
> Why do you think the default rollback (post reboot, for non-committed
> transactions) is a good default?

  I think that's the expected one, basically if the interface commands
lead to an unreachable host, at least thing are preserved on reboot,
that's in-fine the goal of the whole transaction mechanism.

> When/where is that automatic rollback enforced? (I could not find it in
> the patches). Does it trigger a log message too?
> 
> Do you think it may make sense to have that default behavior controlled
> by
> a (global, ie, not per-interface) parameter?

  global parameters to the library would be a really bad idea. a
parameter in a shared config file for netcf would be less troublesome.
But I would prefer bhaviour controlled from the API, and in that case
we can still do this using the flags parameters later on.

> I am not suggesting the introduction of such parameter (but I would not
> be against it), but I would suggest a 4th virsh command to list at
> least the interfaces with a pending (ie, not committed yet) transaction.

  yes that would be an useful extension but it should not prevent
pushing the current code.

  The current API set looks fine to me, so ACK on this patch

Daniel

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