Re: [Linuxptp-users] PTP4L syncing on (gPTP aware) switch A, but not B

[Axel H. <aho...@gm...>]

On Thu, Feb 19, 2015 at 04:05PM +0100, Richard Cochran wrote:
> On Thu, Feb 19, 2015 at 02:00:16PM +0100, Axel Holzinger wrote:
> > Hi all,
> >
> > I have two gPTP aware switches here and a PC with i210 and with switch A
> > ptp4l is syncing fine, while with switch B not. Could anybody point me
in a
> > direction how I can find out what ptp4l doesn't like regarding switch B.
It
> > always selects itself as best master continously (i210 MAC is
> > a0-36-9f-47-60-48). Prios are the same for switch A and B.
> 
> Increase the message level to take a look at the asCapable port
> variable.  There are quite a number of conditions.
> 
> Some other ideas:
> 
> Use wireshark to find out what, if any, messages are being exchanged.
> 
> In port.c, there are quite a few places where silently we drop invalid
> messages.  You can hack in a few debugging statements to find out what
> is going on, especially WRT asCapable.

Well, it was a combination of all three tips. Finally I found out that
gPTP.cfg sets path_trace_enabled to 1 while switch B doesn't send a path
trace TLV. That was the reason for ptp4l to drop the announce message.

Thanks a lot!
Axel