[Libvir] Network blocking issue

[Daniel Veillard]

On Mon, Sep 17, 2007 at 03:57:03PM +0100, Richard W.M. Jones wrote:
> Daniel P. Berrange wrote:
> >My definition is that TCP should keep retrying until I plug the cable back
> >in, so I don't get unneccessary failures if i'm just switching cables
> >around. Likewise if there's temporary outages anywhere else in the link
> >between the client & server.
> 
> Yes actually I agree with you on that one.  On the other hand there is 
> no way for Shuveb to set TCP socket options on the socket other than 
> making a private copy of the libvirt code and hacking it.  So a patch to 
> add yet another query string flag to the remote URI or to expose the 
> remote socket somehow might be acceptable.

  Expectations will vary according to environments. But 15mn is *way* over
what I would accept in a distributed system environment. On the other hand
when ssh resumes the connection fine if I suspend my laptop for 30mn is
a a feature. That's why I ask for a way to set the timeout, I don't think 
we will be able to find a value which will please everybody.
  I'm not too fond of using an extension to the URI, I think this gets over
what URI were designed for. Either giving an access to the socket descriptor
(beware this may generate a future Windows portability problem), or provide
a specific tuning API (not nice but relatively safe). Since calls are
synchronous the app may change the Connection timeout before issuing some
calls like Create or Migrate.

Daniel

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