Re: [Linuxptp-devel] mcast_bind patch

[Keller, J. E <jac...@in...>]

> -----Original Message-----
> From: Keller, Jacob E
> Sent: Friday, March 15, 2019 11:23 AM
> To: 'Robert Carter' <rob...@oc...>; linuxptp-
> de...@li...
> Subject: RE: [Linuxptp-devel] mcast_bind patch
> 
> > -----Original Message-----
> > From: Robert Carter [mailto:rob...@oc...]
> > Sent: Friday, March 15, 2019 11:18 AM
> > To: Keller, Jacob E <jac...@in...>; linuxptp-
> de...@li...
> > Subject: Re: [Linuxptp-devel] mcast_bind patch
> >
> > > It sounds like the problem isn't "it picked the subnet I didn't want"
> > > but rather "different instances of ptp4l didn't consistently pick the
> > > same subnet, but I don't really care which one they pick as long as
> > > it's stable"?
> > >
> > > If it's the former, I'd rather see some sort of option that lets you
> > > specify the subnet. However, being deterministic is reasonably
> > > useful.
> > >
> > > Is my description of the second option accurate? Can you describe the
> > > symptoms that happen when the wrong subnet is chosen?
> >
> > This issue and patch precede me, and the historical information is
> > incomplete, so I recompiled without our patch and ran some tests.
> >
> > I'd put the problem in the "it picked the subnet I didn't want" bucket.
> > Worse, it (ptp4l) also picked the "wrong" interface.
> >
> > Without the patch, ptpl4 is sending Sync and Announce messages out the
> > incorrect interface and using a source IP address that isn't on the "-i"
> > argument interface.
> >
> > ptp4l is bound to eno1 which has two address:
> >      169.254.52.4/16
> >      169.254.53.4/16
> >
> > But Sync and Announce traffic is being sourced from 10.10.100.188, which
> > is on en02. Oy vey!
> >
> > Note, I'm building off the 2.0.0 tag, but that makes no difference. The
> > multicast binding code hasn't changed.
> >
> 
> That seems weird. We should be obtaining the interface index using
> sk_interface_index.
> 
> I suspect that code is what is wrong.
> 

What version of the Linux kernel are you using?

Thanks,
Jake