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diff --git a/contrib/ntp/html/miscopt.htm b/contrib/ntp/html/miscopt.htm index af5ee3c..348bc3e 100644 --- a/contrib/ntp/html/miscopt.htm +++ b/contrib/ntp/html/miscopt.htm @@ -1,162 +1,279 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.01 [en] (Win95; I) [Netscape]"> - <TITLE>Miscellaneous Options -</TITLE> -</HEAD> -<BODY> - -<H3> -Miscellaneous Options</H3> - -<HR> -<DL> -<DT> -<TT>broadcastdelay <I>seconds</I></TT></DT> - -<DD> -The broadcast and multicast modes require a special calibration to determine -the network delay between the local and remote servers. Ordinarily, this -is done automatically by the initial protocol exchanges between the local -and remote servers. In some cases, the calibration procedure may fail due -to network or server access controls, for example. This command specifies -the default delay to be used under these circumstances. Typically (for -Ethernet), a number between 0.003 and 0.007 seconds is appropriate. The -default when this command is not used is 0.004 seconds.</DD> - -<DD> - </DD> - -<DT> -<TT>trap <I>host_address</I> [port <I>port_number</I>] [interface <I>interface_address</I>]</TT></DT> - -<DD> -This command configures a trap receiver at the given host address and port -number for sending messages with the specified local interface address. -If the port number is unspecified. a value of 18447 is used. If the interface -address is not specified, the message is sent with a source address of -the local interface the message is sent through. Note that on a multihomed -host the interface used may vary from time to time with routing changes.</DD> - -<DD> -The trap receiver will generally log event messages and other information -from the server in a log file. While such monitor programs may also request -their own trap dynamically, configuring a trap receiver will ensure that -no messages are lost when the server is started.</DD> - -<DD> - </DD> - -<DT> -<TT>setvar <I>variable</I> [default]</TT></DT> - -<DD> -This command adds an additional system variable. These variables can be -used to distribute additional information such as the access policy. If -the variable of the form <TT><I>name</I> = <I>value</I></TT> is followed -by the <TT>default</TT> keyword, the variable will be listed as part of -the default system variables (<TT>ntpq rv</TT> command). These additional -variables serve informational purposes only. They are not related to the -protocol other that they can be listed. The known protocol variables will -always override any variables defined via the <TT>setvar</TT> mechanism. -There are three special variables that contain the names of all variable -of the same group. The <TT>sys_var_list</TT> holds the names of all system -variables. The <TT>peer_var_list</TT> holds the names of all peer variables -and the <TT>clock_var_list</TT> holds the names of the reference clock -variables.</DD> - -<DD> - </DD> - -<DT> -<TT>logfile <I>logfile</I></TT></DT> - -<DD> -This command specifies the location of an alternate log file to be used -instead of the default system <TT>syslog</TT> facility.</DD> - -<DD> - </DD> - -<DT> -<TT>logconfig <I>configkeyword</I></TT></DT> - -<DD> -This command controls the amount and type of output written to the system -<TT>syslog</TT> facility or the alternate <TT>logfile</TT> log file. By -default, all output is turned on. All <I><TT>configkeyword</TT></I> keywords -can be prefixed with <TT>=</TT>, <TT>+</TT> and <TT>-</TT>, where <TT>=</TT> -sets the <TT>syslogmask</TT>, <TT>+</TT> adds and <TT>-</TT> removes messages. -<TT>syslog messages</TT> can be controlled in four classes (, <TT>peer</TT>, -<TT>sys</TT> and <TT>sync</TT>). Within these classes four types of messages -can be controlled.</DD> - -<DD> -Informational messages (<TT>info</TT>) control configuration information. -Event messages (<TT>events</TT>) control logging of events (reachability, -synchronization, alarm conditions). Statistical output is controlled with -the <TT>statistics</TT> keyword. The final message group is the status -messages. This describes mainly the synchronizations status. Configuration -keywords are formed by concatenating the message class with the event class. -The <TT>allprefix</TT> can be used instead of a message class. A message -class may also be followed by the <TT>all</TT> keyword to enable/disable -all messages of the respective message class.</DD> - -<DD> -Thus, a minimal log configuration could look like this:</DD> - -<DD> -<TT>logconfig = syncstatus +sysevents</TT></DD> - -<DD> -This would just list the synchronizations state of <TT>ntpd</TT> and the -major system events. For a simple reference server, the following minimum -message configuration could be useful:</DD> - -<DD> -<TT>logconfig = syncall +clockall</TT></DD> - -<DD> -This configuration will list all clock information and synchronization -information. All other events and messages about peers, system events and -so on is suppressed.</DD> -</DL> - -<H4> -Variables</H4> -Most variables used by the NTP protocol can be examined with the <TT>ntpdc</TT> -(mode 7 messages) and the <TT>ntpq</TT> (mode 6 messages). Currently, very -few variables can be modified via mode 6 messages. These variables are -either created with the <TT>setvar</TT> directive or the leap warning bits. -The leap warning bits can be set in the <TT>leapwarning</TT> variable up -to one month ahead. Both the <TT>leapwarning</TT> and <TT>leapindication</TT> -variables have a slightly different encoding than the usual leap bits interpretation: -<DL> -<DT> -<TT>00</TT></DT> - -<DD> -The daemon passes the leap bits of its synchronization source (usual mode -of operation).</DD> - -<DT> -<TT>01/10</TT></DT> - -<DD> -A leap second is added/deleted (operator forced leap second).</DD> - -<DT> -<TT>11</TT></DT> - -<DD> -Leap information from the synchronizations source is ignored (thus <TT>LEAP_NOWARNING</TT> -is passed on).</DD> -</DL> - -<HR> -<ADDRESS> -David L. Mills (mills@udel.edu)</ADDRESS> - -</BODY> -</HTML> +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"> +<html> +<head> +<meta name="generator" content="HTML Tidy, see www.w3.org"> +<title>Miscellaneous Options</title> +</head> +<body> +<h3>Miscellaneous Options</h3> + +<img align="left" src="pic/boom3.gif" alt="gif"><a href= +"http://www.eecis.udel.edu/~mills/pictures.htm">from <i>Pogo</i>, +Walt Kelly</a> + +<p>We have three, now looking for more.<br clear="left"> +</p> + +<hr> +<dl> +<dt><tt>broadcastdelay <i>seconds</i></tt></dt> + +<dd>The broadcast and multicast modes require a special calibration +to determine the network delay between the local and remote +servers. Ordinarily, this is done automatically by the initial +protocol exchanges between the client and server. In some cases, +the calibration procedure may fail due to network or server access +controls, for example. This command specifies the default delay to +be used under these circumstances. Typically (for Ethernet), a +number between 0.003 and 0.007 seconds is appropriate. The default +when this command is not used is 0.004 seconds.</dd> + +<dt><tt>driftfile <i>driftfile</i></tt></dt> + +<dd>This command specifies the name of the file used to record the +frequency offset of the local clock oscillator. If the file exists, +it is read at startup in order to set the initial frequency offset +and then updated once per hour with the current frequency offset +computed by the daemon. If the file does not exist or this command +is not given, the initial frequency offset is assumed zero. In this +case, it may take some hours for the frequency to stabilize and the +residual timing errors to subside. + +<p>The file format consists of a single line containing a single +floating point number, which records the frequency offset measured +in parts-per-million (PPM). The file is updated by first writing +the current drift value into a temporary file and then renaming +this file to replace the old version. This implies that <tt> +ntpd</tt> must have write permission for the directory the drift +file is located in, and that file system links, symbolic or +otherwise, should be avoided.</p> +</dd> + +<dt><tt>enable [auth | bclient | calibrate | kernel | monitor | ntp +| stats]</tt><br> +<tt>disable [auth | bclient | calibrate | kernel | monitor | ntp | +stats</tt></dt> + +<dd>Provides a way to enable or disable various server options. +Flags not mentioned are unaffected. Note that all of these flags +can be controlled remotely using the <a href="ntpdc.htm"><tt> +ntpdc</tt></a> utility program.</dd> + +<dd> +<dl> +<dt><tt>bclient</tt></dt> + +<dd>When enabled, this is identical to the <tt>broadcastclient</tt> +command. The default for this flag is <tt>disable</tt>.</dd> + +<dt><tt>calibrate</tt></dt> + +<dd>Enables the calibration facility, which automatically adjusts +the <tt>time1</tt> values for each clock driver to display the same +offset as the currently selected source or kernel discipline +signal. See the <a href="refclock.htm">Reference Clock Drivers</a> +for further information. The default for this flag is <tt> +disable</tt>.</dd> + +<dt><tt>kernel</tt></dt> + +<dd>Enables the precision-time kernel support for the <tt> +ntp_adjtime()</tt> system call, if implemented. Ordinarily, support +for this routine is detected automatically when the NTP daemon is +compiled, so it is not necessary for the user to worry about this +flag. It flag is provided primarily so that this support can be +disabled during kernel development. The default for this flag is +<tt>enable</tt>.</dd> + +<dt><tt>monitor</tt></dt> + +<dd>Enables the monitoring facility. See the <tt>ntpdc</tt> program +and the <tt>monlist</tt> command or further information. The +default for this flag is <tt>enable</tt>.</dd> + +<dt><tt>ntp</tt></dt> + +<dd>Enables the server to adjust its local clock by means of NTP. +If disabled, the local clock free-runs at its intrinsic time and +frequency offset. This flag is useful in case the local clock is +controlled by some other device or protocol and NTP is used only to +provide synchronization to other clients. In this case, the local +clock driver can be used to provide this function and also certain +time variables for error estimates and leap-indicators. See the <a +href="refclock.htm">Reference Clock Drivers</a> page for further +information. The default for this flag is <tt>enable</tt>.</dd> + +<dt><tt>stats</tt></dt> + +<dd>Enables the statistics facility. See the <a href="monopt.htm"> +Monitoring Options</a> page for further information. The default +for this flag is <tt>enable</tt>.</dd> +</dl> +</dd> + +<dt><tt>logconfig <i>configkeyword</i></tt></dt> + +<dd>This command controls the amount and type of output written to +the system <tt>syslog</tt> facility or the alternate <tt> +logfile</tt> log file. By default, all output is turned on. All <i> +<tt>configkeyword</tt></i> keywords can be prefixed with <tt> +=</tt>, <tt>+</tt> and <tt>-</tt>, where <tt>=</tt> sets the <tt> +syslogmask</tt>, <tt>+</tt> adds and <tt>-</tt> removes messages. +<tt>syslog messages</tt> can be controlled in four classes +(<tt>clock</tt>, <tt>peer</tt>, <tt>sys</tt> and <tt>sync</tt>). +Within these classes four types of messages can be controlled.</dd> + +<dd>Informational messages (<tt>info</tt>) control configuration +information. Event messages (<tt>events</tt>) control logging of +events (reachability, synchronization, alarm conditions). +Statistical output is controlled with the <tt>statistics</tt> +keyword. The final message group is the status messages. This +describes mainly the synchronizations status. Configuration +keywords are formed by concatenating the message class with the +event class. The <tt>all</tt> prefix can be used instead of a +message class. A message class may also be followed by the <tt> +all</tt> keyword to enable/disable all messages of the respective +message class.</dd> + +<dd>Thus, a minimal log configuration could look like this: + +<p><tt>logconfig=syncstatus +sysevents</tt></p> + +<p>This would just list the synchronizations state of <tt>ntpd</tt> +and the major system events. For a simple reference server, the +following minimum message configuration could be useful:</p> + +<p><tt>logconfig=syncall +clockall</tt></p> + +<p>This configuration will list all clock information and +synchronization information. All other events and messages about +peers, system events and so on is suppressed.</p> +</dd> + +<dt><tt>logfile <i>logfile</i></tt></dt> + +<dd>This command specifies the location of an alternate log file to +be used instead of the default system <tt>syslog</tt> +facility.</dd> + +<dt><tt>setvar <i>variable</i> [default]</tt></dt> + +<dd>This command adds an additional system variable. These +variables can be used to distribute additional information such as +the access policy. If the variable of the form <tt><i>name</i> = +<i>value</i></tt> is followed by the <tt>default</tt> keyword, the +variable will be listed as part of the default system variables +(<tt>ntpq rv</tt> command). These additional variables serve +informational purposes only. They are not related to the protocol +other that they can be listed. The known protocol variables will +always override any variables defined via the <tt>setvar</tt> +mechanism. There are three special variables that contain the names +of all variable of the same group. The <tt>sys_var_list</tt> holds +the names of all system variables. The <tt>peer_var_list</tt> holds +the names of all peer variables and the <tt>clock_var_list</tt> +holds the names of the reference clock variables.</dd> + +<dt><tt>tinker [ step <i>step</i> | panic <i>panic</i> | dispersion +<i>dispersion</i> | stepout <i>stepout</i> | minpoll <i>minpoll</i> +]</tt></dt> + +<dd>This command can be used to alter several system variables in +very exceptional circumstances. It should occur in the +configuration file before any other configuration options. The +default values of these variables have been carefully optimized for +a wide range of network speeds and reliability expectations. In +general, they interact in intricate ways that are hard to predict +and some combinations can result in some very nasty behavior. Very +rarely is it necessary to change the default values; but, some +folks can't resist twisting the knobs anyway and this command is +for them. Emphasis added: twisters are on their own and can expect +no help from the support group. + +<p>All arguments are in floating point seconds or seconds per +second. The <tt>minpoll</tt> argument is an integer in seconds to +the power of two. The variables operate as follows:</p> +</dd> + +<dd> +<dl> +<dt><tt>step <i>step</i></tt></dt> + +<dd>The argument becomes the new value for the step threshold, +normally 0.128 s. If set to zero, step adjustments will never +occur. In general, if the intent is only to avoid step adjustments, +the step threshold should be left alone and the <tt>-x</tt> command +line option be used instead.</dd> + +<dt><tt>panic <i>panic</i></tt></dt> + +<dd>The argument becomes the new value for the panic threshold, +normally 1000 s. If set to zero, the panic sanity check is disabled +and a clock offset of any value will be accepted.</dd> + +<dt><tt>dispersion <i>dispersion</i></tt></dt> + +<dd>The argument becomes the new value for the dispersion increase +rate, normally .000015.</dd> + +<dt><tt>stepout <i>stepout</i></tt></dt> + +<dd>The argument becomes the new value for the watchdog timeout, +normally 900 s.</dd> + +<dt><tt>minpoll <i>minpoll</i></tt></dt> + +<dd>The argument becomes the new value for the minimum poll +interval used when configuring multicast client, manycast client +and , symmetric passive mode association. The value defaults to 6 +(64 s) and has a lower limit of 4 (16 s).</dd> + +<dt><tt>allan <i>allan</i></tt></dt> + +<dd>The argument becomes the new value for the minimum Allan +intercept, which is a parameter of the PLL/FLL clock discipline +algorithm. The value defaults to 1024 s, which is also the lower +limit.</dd> + +<dt><tt>huffpuff <i>huffpuff</i></tt></dt> + +<dd>The argument becomes the new value for the experimental +huff-n'-puff filter span, which determines the most recent interval +the algorithm will search for a minimum delay. The lower limit is +900 s (15 m), but a more reasonable value is 7200 (2 hours). There +is no default, since the filter is not enabled unless this command +is given.</dd> +</dl> +</dd> + +<dt><tt>trap <i>host_address</i> [port <i>port_number</i>] +[interface <i>interface_address</i>]</tt></dt> + +<dd>This command configures a trap receiver at the given host +address and port number for sending messages with the specified +local interface address. If the port number is unspecified, a value +of 18447 is used. If the interface address is not specified, the +message is sent with a source address of the local interface the +message is sent through. Note that on a multihomed host the +interface used may vary from time to time with routing changes. + +<p>The trap receiver will generally log event messages and other +information from the server in a log file. While such monitor +programs may also request their own trap dynamically, configuring a +trap receiver will ensure that no messages are lost when the server +is started.</p> +</dd> +</dl> + +<h4>Files</h4> + +<tt>ntp.drift</tt> frequency compensation (PPM) + +<hr> +<a href="index.htm"><img align="left" src="pic/home.gif" alt= +"gif"></a> + +<address><a href="mailto:mills@udel.edu">David L. Mills +<mills@udel.edu></a></address> +</body> +</html> + |
