Thorsten Mühlfelder wrote:
In my understanding my server is a stratum 1 with reference identifier LOCL. Also I chose reference timestamp as last time correction by SNTP. Is this correct?
Strictly speaking it is an invalid SNTP server as SNTP clients are not allowed to be SNTP servers (the standard strongly discourages, which in formal RFC language probably means "SHOULD NOT"). So everything else is rather arbitrary.
I also wonder about the precision an root dispersion settings, as the RTC only has a resolution of 1 second.
I'm not sure that all of these are defined for SNTP, but if they are, precision is 0. I would guess that root dispersion would have to be 35ms/second of uptime, plus the results of the standard computation for an upstream NTP server, maybe using suitable guesses for any parameters that specifically derive from the NTP model. Normally one uses 15ms/s, but that assumes that some attempt has been made to correct the static frequency error.
Reference identifier should be the first 32 bits of the MD5 hash of the IPv6 or NSAP address of the the server used at startup, and reference time should be the startup time. (If you use LOCL as reference identifier, I believe reference time should be now and root dispersion should be zero, but, generally, the local "clock" driver is a deliberate protocol violation.)
Stratum is either one greater than the server used at start-up, if claiming that as the reference, or 1 if you are pretending LOCL is really a reference clock. However I think that best practice for ntpd servers with LOCL should apply and you should actually claim stratum 10, with LOCL.
A low stratum is OK when claiming the real source, as root dispersion will disqualify you before you do too much damage.
Thanks for any help, I'd like to set it up the right way.
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