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7: Information on compiling and executing ntpd under Solaris.
8: <BR>
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: <P>
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: <P>
16: <H3>All Solaris versions</H3>
17: <P>
18: We have a report that says starting with Solaris 2.6 we should leave
19: <I>dosynctodr</I> alone.
20: <A HREF="solaris-dosynctodr.html">Here is the report</A>.
21: <P>
22: Proper operation of ntp under Solaris may require setting the kernel
23: variable <I>dosynctodr</I> 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: <P>
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: <P>
39: Instead of the <I>tick</I> 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: <I>nsec_per_tick</I> and <I>usec_per_tick</I>.
44: <P>
45: <I>nsec_per_tick</I> and <I>usec_per_tick</I> 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: <P>
51: On UltraSPARC systems, <I>nsec_per_tick</I> and <I>usec_per_tick</I>
52: are ignored in favor of the <I>cpu_tick_freq</I> variable, which
53: should be automatically be determined by the PROM in an accurate
54: fashion.
55: <P>
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: <P>
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: <P>
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: <P>
73: <H3>Solaris 2.5 and 2.5.1</H3>
74: <P>
75: On UltraSPARC systems, calculation of <I>cpu_tick_freq</I> 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: <P>
83: <HR>
84: <H2>OLD DATA</H2>
85: <STRONG>I can't vouch for the accuracy the information below this
86: rule. It may be significantly dated or incorrect.</STRONG>
87: <P>
88: <P>
89: <H3>Solaris 2.2</H3>
90: <P>
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 <I>tickadj</I>
97: kernel variable.
98: <P>
99: <H3>Solaris 2.1</H3>
100: (This originally written by William L. Jones <jones@chpc.utexas.edu>)
101: <P>
102: Solaris 2.1 contains fairly traditional clock code, with <I>tick</I>
103: and <I>tickadj</I>.
104: <P>
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: <BR>ntpdate -v server1 server2
111: <BR>sleep 20
112: <BR>ntpdate -v server1 server2
113: <BR>sleep 20
114: <BR>tickadj -a 200
115: <BR>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: <P>
122: The first ntpdate will set the time to within two seconds
123: using settimeofday or it will adjust time using adjtime.
124: <P>
125: The first sleep insures the adjtime has completed for the first ntpdate.
126: <P>
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: <P>
130: The second tickadj set the tick adjust system value to 5 microseconds.
131: <P>
132: The second sleeps insure that adjtime will complete before starting
133: the next xntpd.
134: <P>
135: I tried running with a tickadj of 5 microseconds with out much success.
136: 200 microseconds seems to work well.
137: <P>
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>
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