Dear Miroslav,

thanks for your fast reply. It is working now.

It took me a day to find out that on my CentOS 8 I had to change the 
NetworkManager firewall zone for the bond IF to e.g. 'trusted'. Otherwise I 
would just see the PTP packets with tcpdump in promiscuous mode, but ptp4l did 
not get them ... I think that for 'normal' interfaces this is not the case.

cheers,
Christian

-----Ursprüngliche Nachricht-----
Von: Miroslav Lichvar <mlich...@redhat.com> 
Gesendet: Donnerstag, 12. Dezember 2019 09:34
An: Christian Soenke <csoe...@eso.org>
Cc: linuxptp-users@lists.sourceforge.net
Betreff: Re: [Linuxptp-users] Channel bonding config?

On Thu, Dec 12, 2019 at 07:28:09AM +0000, Christian Soenke wrote:
> Hi,
> 
> I'm trying to set up channel bonding with ptp4l. Few things are not clear to 
> me:
> 
> 
>   1.  I guess the only supported mode is active-backup !?

Yes, for both bonding and teaming, as I understand it.

>   2.  Which interface(s) do I specify to ptp4l? The bond or the slaves? If it 
> is the slaves, do I run one or two instances of ptp4l?

Just one ptp4l instance running on the bond interface and one phc2sys instance 
running in the automatic mode (-a) that will follow ptp4l when switching 
between the slave interfaces.

>   3.  Any other restrictions, e.g. ports must share the same PHC?

They don't have to share the PHC.

> And more in general: are there other recommended ways to achieve redundancy 
> (using default profile, E2E, HW timestamping and UDP multicast). I used 
> timemaster with 2x ptp4l --> phc2sys --> SHM --> chrony - this worked for me, 
> but I didn't get to test performance yet. Could something similar be achieved 
> just with phc2sys somehow switching between two ptp4l instances/ports?

I think two or more independent interfaces (no bonding) in different networks 
or PTP domains should generally work better as they would be all active at the 
same time and the clock would be continuously updated when a link goes down. 
Also, their messurements can be combined, possibly improving accuracy and 
stability. If there are three or more independent time sources, it should work 
even when one of them starts providing wrong time (due to a leap second, 
buggy/old GPS firmware, etc.).

--
Miroslav Lichvar



_______________________________________________
Linuxptp-users mailing list
Linuxptp-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linuxptp-users

Reply via email to