[Libguestfs] virt-p2v migration

[Richard W.M. Jones]

On Sat, Feb 04, 2017 at 02:10:30PM +0100, Tomáš Golembiovský wrote:
> On Sat, 4 Feb 2017 10:15:57 +0000
> "Richard W.M. Jones" <rjones at redhat.com> wrote:
> 
> > On Fri, Feb 03, 2017 at 07:29:07PM +0000, cmc wrote:
> > > Looking on our firewall, it will timeout inactive connections after 15
> > > minutes of inactivity.  
> > 
> > Yes, this will likely break virt-p2v.
> > 
> > > I'm guessing there is no keepalive in the control connections.  
> > 
> > The default for ssh is to use TCP keepalives.  However those are very
> > infrequent (once every 2 hours IIRC), so it won't prevent a firewall
> > with such a short timeout from breaking virt-p2v.
> > 
> > Easiest thing here would be to fix the firewall.  15 minutes is a very
> > short timeout.  Doesn't that cause all kinds of problems for regular
> > SSH usage?
> 
> SSH client has option ServerAliveInterval (in seconds) that instructs
> SSH to send, after period of inactivity, a message through control
> connection and request a response from server. The default is 0, i.e. no
> such messages are sent. The intent is mostly to detect early when
> connection was dropped, but it should also help you with your firewall.
> 
> Hope this helps,

Indeed that does help with most things (except for shell-level
timeouts).  I'll post a patch in a bit.

Thanks,

Rich.

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