Re: [Linuxptp-users] Status file of achieved time synchronization

[Koehrer M. (ETAS/ESW5) <mat...@et...>]

> Sent: Wednesday, February 12, 2014 7:32 PM
> > We don't have a file, but instead you can use the management
> > interface. The 'pmc' management client can be used in a script,
> > like in the example below.
> >
> > Probably you are interested in the CURRENT_DATA_SET, but for gPTP
> > applications there is also TIME_STATUS_NP.
Thanks for the information.
That helps.

What I do not see fully clear is the role of phc2sys.
It is used to synchronize the PTP clock from my Ethernet device to the Linux system clock.
There is likely a drift/offset between this PTP clock and the Linux system clock.
This drift/offset has to be corrected by the phc2sys tool.
What kind of information do I get when I call the  'pmc" management client?
Is it the drift/offset of the PTP clock (Ethernet) or is it the drift/offset of my Linux system clock?

One more question related to phc2sys.
When I use a PC as PTP master, I have to call phc2sys like
# phc2sys -c /dev/ptp -s CLOCK_REALTIME -w
When I use a PC as PTP slave, I have to call it like
# phc2sys -s /dev/ptp -w
If I do not explicitly specify which of the PCs should run as master or slave, there is a negotiation between the available PCs.
One of the PCs will be made the master.
Is there a way to call phc2sys to distinguish automatically between master and slave operation mode?
Or how do I have to call "phc2sys" in the situation when I do not know if the PC will be master or not?

Thanks for any help on this!

Regards

Mathias