i'm a newb and trying to use Ptpd over 2 ubuntu machines. I connected these 2 machines just with a cable (ethernet cable without switch). they're connected directly with a cable.
I successfully managed to work them, but on the slave side i keep seeing numbers like 0.000011542 , what does this mean? how should i read this?
For example , does 0.000011542 mean 11,542 micro-sec ?
if so , isn't is too high?
It's written that PTP can be as precise as 10 nano-secs , but i keep seeing micro-secs?
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I'm trying to use Ptpd over 2 RetHat6.1 machines and I've got you're configuration as well (they're connected directly with a cable).
Looking at the ptpd2.stats.log, created in the /var/run directory I've got for the Offset from Master, values much more greater than yours, such as 0.000834973 seconds (835 microseconds)
Would you kindly give me the configuration files you use to run the ptpd on your machines?
In attachment you can find the configuration file that I use in salve mode. I make one machine working in slaveonly mode and the other in masteronly mode.
Many thanks for your quick answer.
The source code I'm using is ptpd-2.3.0. This is the current version, isn't it?
I found my configuration file in the directory named "test" of the ptpd-2.3.0 project.
Thanks,
Caterina
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Hi,
i'm a newb and trying to use Ptpd over 2 ubuntu machines. I connected these 2 machines just with a cable (ethernet cable without switch). they're connected directly with a cable.
I successfully managed to work them, but on the slave side i keep seeing numbers like 0.000011542 , what does this mean? how should i read this?
For example , does 0.000011542 mean 11,542 micro-sec ?
if so , isn't is too high?
It's written that PTP can be as precise as 10 nano-secs , but i keep seeing micro-secs?
Hi Levant,
I'm trying to use Ptpd over 2 RetHat6.1 machines and I've got you're configuration as well (they're connected directly with a cable).
Looking at the ptpd2.stats.log, created in the /var/run directory I've got for the Offset from Master, values much more greater than yours, such as 0.000834973 seconds (835 microseconds)
Would you kindly give me the configuration files you use to run the ptpd on your machines?
In attachment you can find the configuration file that I use in salve mode. I make one machine working in slaveonly mode and the other in masteronly mode.
Many thanks,
Caterina
Last edit: Caterina 2014-05-05
Hi,
I don't know what exact version of PTPd are you using but for the first time, you should use minimal config (like https://sourceforge.net/p/ptpd/code/HEAD/tree/trunk/src/ptpd2.conf.minimal)
There could be a problem in your configuration file with servo:ki and servo:kp. Default values in current version are
servo:kp = 0.1
servo:ki = 0.001
Jan
Dear Jan,
Many thanks for your quick answer.
The source code I'm using is ptpd-2.3.0. This is the current version, isn't it?
I found my configuration file in the directory named "test" of the ptpd-2.3.0 project.
Thanks,
Caterina
Hi,
if it is "OffsetFromMaster" field, you are right. It is 11.452 us.
With special hardware (special network card), you can reach offset < 100 ns but not with ordinary PC.
±15 us is usual for PC.
It becomes worse with network load and CPU utilisation.
Jan
Last edit: Jan Breuer 2013-06-25