Re: [Linuxptp-users] Configuration for boundary clock with on two-port NIC

[Miroslav L. <mli...@re...>]

On Mon, Oct 02, 2023 at 09:44:19AM +0200, Nils Fuerste wrote:
> Unfortunately, the sync on the server receiving the sync from the BC looks
> like this:
> 
> ptp4l[3297.441]: master offset         42 s2 freq   +9338 path delay      
> 319
> ptp4l[3298.441]: master offset        -10 s2 freq   +9298 path delay      
> 319
> ptp4l[3299.441]: master offset         19 s2 freq   +9324 path delay      
> 319

That doesn't look too bad.

> Is there a way to improve the configuration? I found the boundary_clock_jbod
> parameter but setting it to 1 didn't improve the sync.

jbod is only needed when the ports don't share the same clock. It
degrades the sync quality.

> Can someone provide a
> configuration for a simple BC setup with one two-port NIC? What is the sync
> quality I can expect? Any help is appreciated! Thanks in advance!

It depends on the hardware. What NIC do you have?

One thing you can try is to shorten the sync interval and decrease the
PI constants, also on the client's port of the server to minimize the
frequency noise transferred to the client.

-- 
Miroslav Lichvar