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Tue May 29 12:08:38 2012 UTC (12 years, 5 months ago) by misho
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ntp 4.2.6p5

1: <HTML> 2: <HEAD> 3: <TITLE>Solaris hints and kinks</title><link href="scripts/style.css" type="text/css" rel="stylesheet"> 4: 5: </HEAD> 6: <BODY> 7: Information on compiling and executing ntpd under Solaris. 8:   9: Last Updated: Sun Jun 21 01:32:18 EDT 1998, 10: John Hawkinson, 11: <! -- This is deliberately not a mailto -- > <jhawk@MIT.EDU> 12:  13: If you're not running Solaris 2.5.1 or later, it is likely 14: that you will have problems; upgrading would be a really good plan. 15:  16: <H3>All Solaris versions</H3> 17:  18: We have a report that says starting with Solaris 2.6 we should leave 19: dosynctodr alone. 20: <A HREF="solaris-dosynctodr.html">Here is the report</A>. 21:  22: Proper operation of ntp under Solaris may require setting the kernel 23: variable dosynctodr to zero (meaning "do not synchronize the clock 24: to the hardware time-of-day clock"). This can be done with the 25: tickadj utility: 26: <BLOCKQUOTE><TT> 27: tickadj -s 28: </TT></BLOCKQUOTE> 29: If you prefer, it can also be done with the native Solaris kernel debugger: 30: <BLOCKQUOTE><TT> 31: echo dosynctodr/W0 | adb -k -w /dev/ksyms /dev/mem 32: </BLOCKQUOTE></TT> 33:  34: Or, it can also be set by adding a line to /etc/system: 35: <BLOCKQUOTE><TT> 36: set dosynctodr = 0 37: </BLOCKQUOTE></TT> 38:  39: Instead of the tick kernel variable, which many operating 40: systems use to control microseconds added to the system time every 41: clock tick (c.f. <A HREF="../notes.html#frequency_tolerance">Dealing 42: with Frequency Tolerance Violations</A>), Solaris has the variables 43: nsec_per_tick and usec_per_tick. 44:  45: nsec_per_tick and usec_per_tick control the number of 46: nanoseconds and microseconds, respectively, added to the system clock 47: each clock interrupt. Enterprising souls may set these based on 48: information collected by ntpd in the <CODE>/etc/ntp.drift</CODE> file 49: to correct for individual hardware variations. 50:  51: On UltraSPARC systems, nsec_per_tick and usec_per_tick 52: are ignored in favor of the cpu_tick_freq variable, which 53: should be automatically be determined by the PROM in an accurate 54: fashion. 55:  56: In general, the same ntp binaries should not be used across multiple 57: operating system releases. There is enough variation in the core operating 58: system support for timekeeping that a rebuild of ntpd for the idiosyncracies 59: of your specific operating system version is advisable. 60:  61: It is recommended that ntp be started via a script like <A 62: HREF="solaris.xtra.S99ntpd">this one</A>, installed in 63: <CODE>/etc/init.d/ntpd</CODE> with a symbol link from 64: <CODE>/etc/rc2.d/S99ntpd</CODE>. 65: 66: <H3>Solaris 2.6</H3> 67:  68: Solaris 2.6 adds support for kernel PLL timekeeping, but breaks this 69: support in such a fashion that using it worse than not. This is <A 70: HREF="solaris.xtra.4095849"> SUN Bug ID 4095849</A>, and it is not yet 71: fixed as of June 1998. 72:  73: <H3>Solaris 2.5 and 2.5.1</H3> 74:  75: On UltraSPARC systems, calculation of cpu_tick_freq is broken 76: such that values that are off by significant amounts may be used 77: instead. This unfortunately means that ntpd may have severe problems 78: keeping synchronization. This is <A HREF="solaris.xtra.4023118"> SUN Bug ID 79: 4023118</A>. Bryan Cantrill <! -- <bmc@eng.sun.com> --> of Sun 80: posted <A HREF="solaris.xtra.patchfreq">patchfreq</A>, a workaround script, 81: to comp.protocols.time.ntp in March of 1997. 82:  83: <HR> 84: <H2>OLD DATA</H2> 85: I can't vouch for the accuracy the information below this 86: rule. It may be significantly dated or incorrect. 87:  88:  89: <H3>Solaris 2.2</H3> 90:  91: Solaris 2.2 and later contain completely re-written clock code to 92: provide high resolution microsecond timers. A benefit of the 93: re-written clock code is that adjtime does not round off its 94: adjustments, so ntp does not have to compensate for this 95: rounding. Under Solaris 2.2 and later, ntp #define's 96: <CODE>ADJTIME_IS_ACCURATE</CODE>, and does not look for the tickadj 97: kernel variable. 98:  99: <H3>Solaris 2.1</H3> 100: (This originally written by William L. Jones <jones@chpc.utexas.edu>) 101:  102: Solaris 2.1 contains fairly traditional clock code, with tick 103: and tickadj. 104:  105: Since settimeofday under Solaris 2.1 only sets the seconds part of timeval 106: care must be used in starting xntpd. I suggest the following start 107: up script: 108: <BLOCKQUOTE><TT> 109: tickadj -s -a 1000 110:  ntpdate -v server1 server2 111:  sleep 20 112:  ntpdate -v server1 server2 113:  sleep 20 114:  tickadj -a 200 115:  xntpd 116: </TT></BLOCKQUOTE> 117: 118: The first tickadj turns of the time of day clock and sets the tick 119: adjust value to 1 millisecond. This will insure that an adjtime value 120: of at most 2 seconds will complete in 20 seconds. 121:  122: The first ntpdate will set the time to within two seconds 123: using settimeofday or it will adjust time using adjtime. 124:  125: The first sleep insures the adjtime has completed for the first ntpdate. 126:  127: The second ntpdate will use adjtime to set the time of day since the 128: clock should be within 2 seconds of the correct time. 129:  130: The second tickadj set the tick adjust system value to 5 microseconds. 131:  132: The second sleeps insure that adjtime will complete before starting 133: the next xntpd. 134:  135: I tried running with a tickadj of 5 microseconds with out much success. 136: 200 microseconds seems to work well. 137:  138: <HR> 139: Prior versions of this file had major text contributed by: 140: <MENU> 141: <LI>Denny Gentry <denny@eng.sun.com> 142: </MENU> 143: <BODY> 144: </HTML>