ptp multicast address channels and ptp-v1

[saspace]

Hello all,
I have a convoluted situation in one of my setups. here are the details:
1) It is running PTPv1 using the following options:
(for pseudo master running NTP + PTP master)
/usr/sbin/ptpd -n DOMAIN_X -D -b bond0 -s 1 -i NTP -t -f /var/log/ptpd.log
For clients:
/usr/sbin/ptpd -n DOMAIN_X -D -b bond0 -f /var/log/ptpd.log
When I run /usr/sbin/ptpd --long-help , I get following help ==>
Usage: ptpd [OPTION]

-? show this page

-c run in command line (non-daemon) mode
-f FILE send output to FILE
-d display stats
-D display stats in .csv format

-x do not reset the clock if off by more than one second
-t do not adjust the system clock
-a NUMBER,NUMBER specify clock servo P and I attenuations
-w NUMBER specify one way delay filter stiffness

-b NAME bind PTP to network interface NAME
-u ADDRESS also send uni-cast to ADDRESS
-l NUMBER,NUMBER specify inbound, outbound latency in nsec

-o NUMBER specify current UTC offset
-e NUMBER specify epoch NUMBER
-h specify half epoch

-y NUMBER specify sync interval in 2^NUMBER sec
-m NUMBER specify max number of foreign master records

-g run as slave only
-p make this a preferred clock
-s NUMBER specify system clock stratum
-i NAME specify system clock identifier
-v NUMBER specify system clock allen variance

-n NAME specify PTP subdomain name (not related to IP or DNS)

-k NUMBER,NUMBER send a management message of key, record, then exit

The Qns is:
I took a tcpdump at one of the Slaves and found that the master is sending data in multicast channel 224.0.1.130. I know that the default channel is 224.0.1.129 but cound not find where this channel .130 is configured. Is it compiled in the code?

My apology for asking the ptp-v1 qns.
Thanks

[saspace]

Please help me, Any clue to the channel address 224.0.1.130 will be very helpful.

[saspace]

Further note that I did this:
strings ptpd | grep 224.0.1.130
224.0.1.130
strings ptpd | grep 224.0.1.129
224.0.1.129

So it means both the channel defined . So how is my ptpd picking up non-default channel 224.0.1.130 ?

[Jan Breuer]

Hi,
IEEE1588-2002 (PTP v1) is deprecated and no longer supported.

Everything is because you are defining nondefault and nonstandard domain name.

PTPv1 uses different multicast addresses for different domains. Default multicast address is 224.0.1.129, but it is possible to use 130, 131, 132.

Possible domain names and corresponding addresses are
_DFLT 224.0.1.129
_ALT1 224.0.1.130
_ALT2 224.0.1.131
_ALT3 224.0.1.132

If you use other domain name, it will fall back to 224.0.1.130.

If you don't define domain name at command line, it will use _DFLT 224.0.1.129 for all communication.

[saspace]

I know it is depricated and if I can get these answers then I will be happy.

Did you mean that since I use -n DOMAIN_X, it is using the address 224.0.1.130 ?
Note that in the help it shows, -n NAME specify PTP subdomain name (not related to IP or DNS)

If that is the case then if I remove -n DOMAIN_X it will use 224.0.1.129 ?
Then how do I use .131, .132?

[Jan Breuer]

-n NAME specify PTP subdomain name (not related to IP or DNS)

doesn't mean, that you MUST but that you CAN spacify the domain. So don't use -n at all and you will use default domain with address 224.0.1.129.

As I wrote in previous message,
-n _DFLT will use 224.0.1.129
-n _ALT1 will use 224.0.1.130
-n _ALT2 will use 224.0.1.131
-n _ALT3 will use 224.0.1.132
-n ANYTHING_OTHER will use 224.0.1.130
-n DOMAIN_X will use 224.0.1.130
-n DOMAIN_Y will use 224.0.1.130
etc

[saspace]

Thanks you very much.