On 2010-03-19, David Mills <[email protected]> wrote: > Joe, > > That's a typo; event 16 does not exist. Glad you caught that.
Pretty elaborate typo. Did they mean to give it a number other than 16, or were 50 letters somehow mistyped? > > Dave > > Joseph Gwinn wrote: > >>Dave, >> >>In article <[email protected]>, David Mills <[email protected]> wrote: >> >> >> >>>Joe, >>> >>>You and Dave are working way too hard. The bits and pieces are >>>documented on the ntpq page and on the Event Messages and Status Codes page. >>> >>> >> >>This would be <http://www.eecis.udel.edu/~mills/ntp/html/decode.html#peer>, >>which I didn't know about, but is exactly what I seek. And it wasn't a >>secret >>after all. >> >>But I have a question, a homework example, and a suggestion. >> >>First the question: The Code field of the Peer Status Word is 4 bits wide, >>and >>yet codes are defined for values from 1 to 10 hex (decimal 16), which doesn't >>quite map. How does the code value fit into the field? Wraparound, so 10 >>(TAI) >>becomes zero? >> >> >>The homework example: The PSW word that started this exercise is "963a". If >>I >>understand, this word decodes as follows: >> >>Status field - host_reachable plus persistent_association >> >>Select field - system_peer (gets the star) >> >>Count field - 3 >> >>Code field - become system peer (assuming code values are truncated to 4 >>bits, >>so hex 10 becomes 0) >> >>And 9614 decodes to host_reachable plus persistent_association, system_peer >>(gets the star), count=1, and server_reachable. >> >> >>And the suggestion: I was misled by some of the NTPv4 documentation, >>specifically the NTPv4 peerstats file documentation in >><http://www.eecis.udel.edu/~mills/ntp/html/monopt.html>. >> >>The note under the table defining peerstats record fields reads "The status >>field is encoded in hex format as described in Appendix B of the NTP >>specification RFC 1305". This is no longer really true, as you discuss >>below. >>In particular, codes exceeding 5 are not defined in 1305, and some of the >>definitions appear to have changed (or at least have been clarified) so it >>would >>be helpful to add a pointer to >><http://www.eecis.udel.edu/~mills/ntp/html/decode.html#peer> to monopt.html. >> >> >> >> >>>RFC-1305 was written in 1992. It's been 18 years since then, so you >>>should expect changes from time to time. Changes are not done lightly; >>>they reflect updates in the algorithms and interpretation of the >>>statistics and state variables. If the interpretation has not changed, >>>the name and code have not changed. If it has been changed or has become >>>obsolete, the name is not reused. >>> >>> >> >>This is good. There is far too much existing base to do it any other way. >> >>Thanks, >> >>Joe Gwinn >> >> >> >> >>>Dave >>> >>>Joseph Gwinn wrote: >>> >>> >>> >>>>In article >>>><46f5ae0a-93d6-44ea-812f-e4da2ae2c...@a16g2000pre.googlegroups.com>, >>>>Dave Hart <[email protected]> wrote: >>>> >>>> >>>> >>>> >>>> >>>>>There were backward-incompatible changes on May 13, 2008 for ntp-dev >>>>>4.2.5p114: >>>>> >>>>><http://ntp.bkbits.net:8080/ntp-dev/?PAGE=cset&REV=48295cccnu3e5cmGhOzAS7hA- >>>>>pVG3A> >>>>> >>>>>Once again statestr.c is your friend: >>>>> >>>>><http://ntp.bkbits.net:8080/ntp-dev/libntp/statestr.c?PAGE=diffs&REV=4829513 >>>>>7L4-SOuAy6YZauDbZtW6DRg> >>>>> >>>>>If you want to be able to decode these bits for ntpd versions from >>>>>before and after the change correctly, you need to query the version >>>>>string of ntpd, sadly, such as with: >>>>> >>>>>ntpq -c "rv 0 version" >>>>> >>>>> >>>>> >>>>> >>>>So that's how you get the NTP version (rather than the ntpq version)! >>>> >>>>When our sysadmins first installed NTPv4, they used the version command of >>>>ntpq, >>>>which said "4". Check! >>>> >>>>I came by a few days later to look at the purported NTPv4 loopstats and >>>>peerstats files, and (ever suspicious) checked to see what version of NTP >>>>had in >>>>fact generated them. Still NTPv3. The sysadmins had been snookered by >>>>ntpq, >>>>which failed to make unambiguous whose version it was reporting upon. >>>> >>>>This had also happened to me back in the days of NTPv3, but I was saved >>>>because >>>>I knew that "4" could not be the answer. But I never did figure out how to >>>>get >>>>ntpq to tell me the version of the ntp daemon. >>>> >>>> >>>> >>>> >>>> >>>> >>>>>and then parse for 4.2.5p114 or later. The format for the version >>>>>string can include an optional -RC# suffix, and before long, there may >>>>>be releases with a -beta# suffix in the -stable branch, such as >>>>>4.2.6p2-beta1 as a prelude to 4.2.6p2-RC1. >>>>> >>>>> >>>>> >>>>> >>>>Still evolving, rapidly. OK. I will have to find out exactly which >>>>version >>>>I >>>>have. I have no need to decode status from prior versions. I need only to >>>>understand the status codes from what I am running, to understand what is >>>>and is >>>>not working in my system. Fixes have included giving NTP and related >>>>traffic >>>>its own dedicated LAN and LAN ports on the hosts, to reduce buffeting of >>>>NTP >>>>packets and/or the daemon by unrelated but heavy packet traffic. The >>>>buffeting >>>>causes what appear to be large, random, and often asymmetric transport >>>>delays. >>>> >>>>Is there available a written discussion of which changes were made and why? >>>> >>>>This could be worth reading. >>>> >>>>More generally, these backward-incompatible changes will cause great >>>>confusion >>>>and difficulty in transitioning to NTPv4 unless ntpq is kept up to date, >>>>and >>>>the >>>>descriptions of what the various status codes mean are both complete and >>>>correct >>>>- telegraphic summaries are not usually enough for non-developers to >>>>understand. >>>> >>>>Looking at the code you suggested, I also see that the variable names are >>>>the >>>>same as in NTPv3 (and the names imply the original NTPv3 meanings), but the >>>>new >>>>NTPv4 comments on those variables seem to contradict the meanings implied >>>>by >>>>the >>>>names. Not knowing the history makes it difficult to figure out just what >>>>is >>>>now meant. >>>> >>>>Thanks, >>>> >>>>Joe Gwinn >>>> >>>>_______________________________________________ >>>>questions mailing list >>>>[email protected] >>>>http://lists.ntp.org/listinfo/questions >>>> >>>> >>>> >>>> >> >>_______________________________________________ >>questions mailing list >>[email protected] >>http://lists.ntp.org/listinfo/questions >> >> _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
