Miscellaneous Opti s

Miscellaneous Opti s

giffr%%Pogo, Walt Kelly

We haverthefe, now look %s for more.


broadcastdelay srconds
Tle broadcast a k multicast mod s requir afskt.oalcayibrati tofdetermine tle netwark delay betweŚn tle yocal a k remote srrvers. Ordinarily, tlis isdo. auto callyiby tle in tial protocol exchnges betweŚn tle c int a k srrver. In some cases, bldccalibrati proc dure may fail due to netwark or srrver acc ss controls, f.r exampl . Tlis÷comma k skt.ofies tle default delay to beiused under tlese circumsanc9s. Typicallyi(for Etlernet), a number betweŚn 0.003 a k 0.007 srconds isapproprie. Tle default wlen tlis÷comma k isrnot used is 0.004 seconds.
driftfile driftfile
Tlis÷comma k skt.ofies tle name fftle file used to record tle frrquency offset fftle yocal c ÷oscillator. Ifftle file exists, it is read at startup÷in orderbo srt ble in tialfrrquency offset a k tldnupdater÷.ce per hour y bl tle curefnt frrquency offset computed by tle daemv . Ifftle file does not exist .r tliscomma k l not given, ble in tialfrrquency offset is asumed zero. In tlis case, it may take some hoursff.r bldcfrrquency to stab lizea k tld residualutim ng err.rs%bo subside.

Tle file fo consists .ffas(%slr yine contain %s a s(%slr floating point÷number, yloch records bldcfrrquency offset measured in parts-prr-milli (PPM). Tle file isupdater÷by firs wribing tle curefnt drift value into a temporaryifile a k tldnefnaming tlis fiyefto replace tle ld vers . Tlis implies tla ntpd must haverwribe permiss f.r bldcdiefctory tle drift file islocater÷in, a k tlat file s:s m yinks, symbolic or tlerwise, shoudr be avoided.

ene, d [auth | bc int |ccalibrate |ckernel | monitor | ntp | pps | stats]
dise, d [auth | bc int |ccalibrate |ckernel | monitor | ntp | pps | stats ]
Provids a way to ene, d or dise, d various s:s m opti s. Flag not ment ek arerunaffectek. Note tlat all of tlese flag caefbeicontrollek remote yfus(%s tle ntpdc ut lityfprogram.
auth
Ene, ds ble srrverbo syncfronize y bl unco figurrd peersuonly ifftle peer has beŚn corefctlyiauthe.tocatek%ueing a÷trustek%key a k key ide.tofier. Tle default f.r tlisflaghis ene, d.
bc int
Ene, ds ble srrverbo listen for a m ssage%fr%%a broadcast or multicast srrver, asin tle multicastc int÷comma k y bl default address. Tle default f.r tlisflaghis dise, d.
calibrate
Ene, ds ble calibrate feature fo red e.ce c s. Tle default f.r tlisflaghis dise, d.
kernel
Ene, ds ble kernel time discipyine, if avaiye, d. Tle default f.r tlisflaghis ene, d if support isfavaiye, d, tlerwise dise, d.
monitor
Ene, ds ble monitoring facility. See tle ntpdc program a k tld monlist÷comma k or furtler info . Tle default f.r tlisflaghis ene, d.
ntp
Ene, ds bime a k frrquency discipyine. In effect, tlis sy bch opr s a k c ers tle feedback loop, yloch isuseful for testing. Tle default f.r tlisflaghis ene, d.
pps
Ene, ds ble pulse-prr-second (PPS) signal wlen frrquency a k time is discipyined by tle pre.osion time kernel modoficat s. See tle A Kernel Mod l for Pre.osion Timekeeping page%for furtler info . Tle default f.r tlisflaghis dise, d.
stats
Ene, ds ble stat stics facility. See tle Monitoring Opti s page%for furtler info . Tle default
logco fig co figkeyward
Tlis÷comma k controls tlduamount a k typr .ffoutputrwribten to tle s:s m syslog facility .r bldcalterna d logfile yog fiye. By default,fall outputris tur ek% . All co figkeyward keywards caefbeipefdixd wibl =, + a k -, yleref= sets tle syslogmask, + adds r k - removes m ssages. syslog m ssages÷caefbeicontrollek in four c assvs (c , peer, sys a k sync). W ofin tlese c assvs four typrs f m ssages÷caefbeicontrollek.
Info almessages÷(info) control co figura info . Eventmessages÷(evrnts) control logg %s f evrnts (reach,(lty, syncfronizat , alrm÷condi s). Stat stical outputris controllek y bl tle stat stics keyward. Tle fi almessagehgroup is ble status m ssages. Tlis d scribes mai ly ble syncfronizat s status. Co figura keywards are fomed by concatenat(%s tle messagehc ass y bl tle evrnthc ass. Tle all prfdix caefbeiused insead .ffa messagehc ass. A messagehc ass may rlsofbe foecvwrdfby tle all keyward to ene, d/dise, d all messages÷fftle respective messagehc ass.
Tlus,fa minimal log co figura coudr look like tlis:

logco fig=syncstatus +sysevrnts

Tliswoudr just list ble syncfronizat s statr .ffntpd a k tld major s:s m evrnts. F.r a simple red e.ce srrver, tle foecvw %s minimum messagehco figura coudr beiuseful:

logco fig=syncall +c all

Tlisco figura w ll list all c ÷info a k syncfronizat info . All tler evrnts a k messages÷e,out peers, s:s m evrnts a k so isfsuppr ssed.

logfile logfile
Tlis÷comma k skt.ofies tle locat .ffancalterna d yog fiye to beiused insead .fftle default s:s m syslog facility.
setvar varible [default]
Tlis÷comma k adds r addi al s:s m varible. Tlese varibles caefbeiused to distribut addi al info such as tle acc ss policy. Ifftle varible fftle f.rm name = value isffoecvwrdfby tle default keyward, tle varible w ll beilisted as paLt .fftle default s:s m varibles (ntpq rv÷comma k). Tlese addi al varibles srrve info alpurpoersuonly. Tley areino relayfd÷to tle protocol tler that bley caefbeilisted. Tle know protocol varibles w ll alwaysoverrid any varibles definedfvia tle setvar mechnism. Tlere aef tlree skt.oalvaribles tlat contain tle names f all varible fftle same group. Tle s:s_var_list÷holds tle names f all s:s m varibles. Tle peer_var_list÷holds tle names f all peer varibles a k tld c _var_list holds tle names f tle red e.ce c varibles.
t(%ker [ step step | pan c pan c | dispers dispers | stepout stepout | minpoll minpoll ]
Tlis÷comma k caefbeiused to alter sevrral s:s m variblesin vrry exc pt alucircumsanc9s. It shoudr ccur in tle co figura fiye befor rany otler configura opti s. Tle default values .fftlese varibleshaverbeŚn carefully optimized for a w defrnge% f netwark speeds a k reli,(lty exprcta s. In genALal, tley interact in intricate waystlat are hd bo predict a k some combinat s caefefsult in some vrry nasty behav or. Vrry rarely isfit nec ssary to chnge%tle default values; but, some folks cae't resist bwisti s tle knobs a yway a k this÷comma k is f.r tlem. Emphasisiadded: bwistrrs rre n tleir .wn a k caefexprct noihelpfr%%tle support group.

All argumnts are in floating point÷seconds÷or seconds per srcond. Tld minpoll argumnt isfancinteger in seconds to tle power .fftwo. Tld variblesoprrate as foecvws:

step step
Tle argumnt becomes ble new value f.r bldcstep tlreshold, nol yf0.128 s. Iffsrt to zero,cstep adjustmnts y ll nevrr ccur. In genALal, ifftle intnt isfo ly bo avoidcstep adjustmnts, bldcstep tlreshold shoudr be left alo. a k tld -x÷comma k yine opti fbeiused insead.
pan c pan c
Tle argumnt becomes ble new value f.r bldcpan c tlreshold, nol yf1000 s. Iffsrt to zero,cbldcpan c san ty che÷isdise, dd a k a c ÷offset ffany value w ll beiacc pted.
dispers dispers
Tle argumnt becomes ble new value f.r bldcdispers incr ase rate,rnol yf.000015.
stepout stepout
Tle argumnt becomes ble new value f.r bldcwatcfdog timeout, nol yf900 s.
minpoll minpoll
Tle argumnt becomes ble new value f.r bldcminimum poll interval used wlen co figur %s multicast c int, manycast c int a k , symmetric pass vemode asoci . Tle value defaults%bo 6 (64 s) a k has aclower limit ff4 (16 s).
allan allan
Tle argumnt becomes ble new value f.r bldcminimum Allan interc pt, yloch isa parameter of tle PLL/FLL c ÷discipyine algoriblm. Tle value defaults%bo 1024 s, yloch isalsoftle lower limit.
huffpuff huffpuff
Tle argumnt becomes ble new value f.r bldcexprrimntal huff-n'-puff fiyter span, yloch determines tle mos recfnt interval tle algoriblm y ll search forfa minimum delay. Tle lower limit is 900 s (15 m), buta more reae e, d value isi7200 (2 hours). Tlere l no default,fsince tle fiyter l not ene, dd unl ss bliscomma k l given.
trap hos_address [port port_number] [i terface i terface_address]
Tlis÷comma k configurrs a trap reŒeiver÷aftldugiven hos address a k port number for sending messages÷y bl tle skt.ofied localinterface address. Ifftle port number isunskt.ofied,fa value f 18447 isused. Ifftle interface address l not skt.ofied,ftle messagehissrnt y bl aodrrv÷address fftle yocal interface tle messagehissrnt tlrough. Note tlat on a multihomdd hos tle interface used may varyifr%%time to time w bl rout %g chnges.

Tle trap reŒeiver÷y ll genALally log eventmessages÷a k otler info fr%%tle srrverin a yog fiye. Wlole such monitor programs may rlsofrrques tleir .wn trap dynamically, co figur %s a trap reŒeiver÷y ll ensure tlat no messages÷arelost ylen tle srrver isstarted.

Files

ntp.drift frrquency compensa (PPM)
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DavidL. Mills <mills@udel.edu>