[Libguestfs] Thoughts on nbdkit automatic reconnection

[Richard W.M. Jones]

On Thu, Sep 19, 2019 at 07:18:29AM -0500, Eric Blake wrote:
> On 9/19/19 4:50 AM, Richard W.M. Jones wrote:
> > On Wed, Sep 18, 2019 at 01:59:01PM +0100, Richard W.M. Jones wrote:
> >> We have a running problem with the nbdkit VDDK plugin where the VDDK
> >> side apparently disconnects or the network connection is interrupted.
> >> During a virt-v2v conversion this causes the entire operation to fail,
> >> and since v2v conversions take many hours that's not a happy outcome.
> >>
> >> (Aside: I should say that we see many cases where it's claimed that
> >> the connection was dropped, but often when we examine them in detail
> >> the cause is something else.  But it seems like this disconnection
> >> thing does happen sometimes.)
> > 
> > It turns out in the customer case that led us to talk about this, a
> > Checkpoint firewall was forcing the VDDK control connection to be
> > closed after an idle period.
> 
> Would TCP keepalive help here?

Seems as if VDDK already sets this, but perhaps only on the data
connection (as usual the documentation is atrocious).

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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