1. OҦʤu@Ƶ{
@@1.1 Linux u@Ƶ{G at, crontab
@@1.2 Linux W`Ҧʤu@
2. Ȱ@u@Ƶ{
@@2.1 atd ҰʻP at B@觋G /etc/at.deny
@@2.2 ڹB@@u@Ƶ{G at, atq & atrm, batch
3. `檺Ҧʤu@Ƶ{
@@3.1 ϥΪ̪]wG /etc/cron.deny, crontab
@@3.2 tΪ]wG /etc/crontab
@@3.3 @Ǫ`Nƶ
4. iu@
@@4.1 O anacron
@@4.2 anacron P /etc/anacrontab
5. I^U
6. D
7. w糧媺ĳGhttp://phorum.vbird.org/viewtopic.php?t=23889

CӤHΦhΤֳ@Ǭ|Ϊ̬Ou@Au@OҦʪA ҦpC~@[~BCӤ@u@iBCg@\|BCѻݭndF u@hO{ɵoͪAҦpn`qxӳXAݭnAǳƺtI ΦbͬWAҦpC~RHͤBCѪ_ɮɶB٦oʪqj (ڡIuƱѤѳI) oC

WoǨҦʤu@Aq`AonObƾW~קKѰOILAѩڭ̱``bqetGA pGqtίDʪqڭ̪ܡA򤣴NPhFIKKIoӮɭ Linux Ҧʤu@Ƶ{NiHWFI bҼ{wPڭ̦AsAUAڭ̪ Linux iHAܦhȡAҦpGC@ѦW 8:00 nAsWTAñҰʭ֨ӳA_ɡFӤ 12:00 Ʊ Linux iHo@ʫHAlHcAAiHhY\FF t~AbC~ARHͤ骺e@ѡAoʫHAAHKѰOo򭫭n@ѡC

Linux Ҧʤu@OpiƵ{OHҿתƵ{NONoǤu@wư檺y{NI ̪ Linux Ƶ{NOzL crontab P at oӪFIoӪN঳ԣPHNڭ̨@@I

Linux u@Ƶ{G at, cron

qWAڭ̥iHܲMo{ؤu@Ƶ{觋G

@جOҦʪANOCj@wgnӿ쪺ƶF
@جOoʪANOoHNS@ (qj...)

b Linux UpFoӥ\OHNoϥ at P crontab oӦnFoI

at Gat OӥiHBzȰ@NƵ{OALn at ɡA n atd oA (ĤQK) 䴩~CbYǷs distributions Aatd iw]èSҰʡA at oӫON|ĩOILڭ̪ CentOS w]OҰʪI
crontab Gcrontab oӫOҳ]wu@N|`@iUhI i`ɶBpɡBCgBCΨC~Ccrontab FiHϥΫO~Ais /etc/crontab Ӥ䴩C ܩ crontab iHͮĪAȫhO crond oӪAȳI

Uڭ̥ӽͤ@ Linux tΨ쩳bƱA򦳭Yzhu@Ƶ{biOHMA^ӽͤ@ at P crontab oӦnFI

Linux W`Ҧʤu@

pGAgϥιL Linux @}lFAAj|o{ Linux |Dʪڭ̶i@Ǥu@OI 軡۰ʪiuWs (on-line update)B۰ʪi updatedb (ĤCͨ쪺 locate O) sɦWƮwB۰ʪ@nɤR (ҥH root ``|D logwatch H) CoOѩtέn`B@ܡA YǦbIUu@nwɶi檺tGC򥻤W Linux tα`ҦʥȦG

inɪ (log rotate)G
Linux |DʪNtΩҵoͪUظTOUӡAoNOn (ĤQE)C ѩtη|@OnTAҥHnɱN|VӶVjIڭ̪Djɮפeqٷ|yŪgį઺xZA ]AɪNnɸƮ@AªƻPsƤOsAhiHĪOnTCoNO log rotate ȡIo]OtΥnҦȡF
nɤR logwatch G
pGtεoͤFnDBw~BwDAj~T|QOnɤA ]tκ޲znȤ@NORnɡCAiʳzL vim nh˵nɡA]ƤӽFI ڭ̪ CentOS ѤF@{y logwatch zӥDʤRnTAҥHA|o{AA root ѬO|D logwatch HAO`IA̦n]ݬݸӫH󪺤eI
إ locate ƮwG
bĤCڭ̽ͨ쪺 locate OɡA ڭ̪DӫOOzLwgsbɦWƮwӶitΤWɦWdߡCڭ̪ɦWƮwOm /var/lib/mlocate/ C DOAoӸƮw|۰ʧsڡHKKIoNOtΪҦʤu@ҲͪĪGաItη|Dʪi updatedb I
whatis ƮwإG
P locate ƮwAwhatis ]OӸƮwAo whatis OP man page @Ӭd߫OALnϥ whatis OɡA n֦ whatis ƮwAӳoӸƮw]OzLtΪҦʤu@Ƶ{Ӧ۰ʰ檺I
RPM nnɪإG
RPM (ĤGQT) O@سn޲zCѩtΥi|``ܧnA ]An骺swˡBDg`ʧsA|ynɦWtCFKӰlܡAtΤ]ڭ̱NɦW@ӱƧǪOOI ɭԨtΤ]|zLƵ{ RPM ƮwsظmI
ȦsG
YǳnbB@|ͤ@ǼȦsɡAOoӳnɡAoǼȦsɥiä|DʪQC ǼȦsɫhɶʡApGWL@qɶAoӼȦsɴNSĥΤFAɲoǼȦsɴNO@󭫭nu@I _hϺЮeq|QӥCtγzLҦʤu@Ƶ{W tmpwatch OӧRoǼȦsɩOI
PAȦR欰G
pGAw WWW An (@ӦW apache n)AA Linux tγq`N|DʪRӳn骺nɡC PɬYǾһP{ҪTO_LDAڭ̪ Linux tΤ]|ܿ˩MAi۰ˬdI

Atη|i檺Ҧʤu@PAw˪nh観ApGAw˹LhnAYǪAȥ\઺n鳣|WRuA AtδN|hX@ǨҦʤu@oID٦h[FܦhۤvgRuAHΨLĤTOn骺RnA KKIͪ Linux u@qiOD`jI]ohu@ݭniAҥHڭ̷MonAѨҦʤu@Bz觋oI

Aڭ̥ӽͽͳ@u@Ƶ{B@ANO at oӫOB@I

atd ҰʻP at B@觋

nϥγ@u@Ƶ{ɡAڭ̪ Linux tΤWntdoӱƵ{AȡANO atd oӪNC LëDҦ Linux distributions w]|L}AҥHOAYǮɨڭ̥nʱNLҥΤ~C ҥΪk²ANOoˡG

[root@www ~]# /etc/init.d/atd restart
b atd:                          [  Tw  ]
bҰ atd:                          [  Tw  ]

# A]w@U}ɴNҰʳoӪAȡAKoCs}oAӤ@I
[root@www ~]# chkconfig atd on

IOӡybҰ( starting)zت OK աIܱҰʬO`Ioڭ̦bĤQK|ͤΡC pGzuAiHۦ /etc/init.d/atd o shell script h@@@I ^_^C ܩ󨺭 chkconfig AA]iHϥ man d\@UڡIڭĤQKAаաI

at B@觋

JMOu@Ƶ{Aӷ|ͤu@觋AåBNoǤu@ƶi{oIOKI򲣥ͤu@觋Oi檺H ƹWAڭ̨ϥ at oӫOӲͩҭnB@u@AñNoӤu@Hrɪ觋gJ /var/spool/at/ ؿAӤu@K൥ atd oӪAȪλPFCNo²C

LAäOҦHiHi at u@Ƶ{IH]wzѰڡ ܦhDQҿתyj[zA̱`o{NOL̪tηhFܦhǫȵ{ (cracker program)A oǵ{D`iBΤu@Ƶ{Ӱλ`tθTAéwɪ^ǫȹI ҥHoADOA{ibA_hnL̨ϥ at aIFϥ at CީOH

ڭ̥iHQ /etc/at.allow P /etc/at.deny oɮרӶi at ϥέOI [Woɮ׫A at u@pOo˪G

M /etc/at.allow oɮסAgboɮפϥΪ̤~ϥ at ASboɮפϥΪ̫hϥ at (YϨSgb at.deny )F
pG /etc/at.allow sbANM /etc/at.deny oɮסAYgbo at.deny ϥΪ̫hϥ at AӨSbo at.deny ɮפϥΪ̡ANiHϥ at F
pGɮ׳sbAu root iHϥ at oӫOC

zLoӻAڭ̪D /etc/at.allow O޲zY檺觋A /etc/at.deny hP (]bSbɮפAN at F)Cb@몺 distributions Aѩ󰲳]tΤWҦΤ᳣OiHA ]tγq`|Od@ӪŪ /etc/at.deny ɮסANO\ҦHϥ at ON (ziHۦˬd@Uɮ)C LAU@AƱ榳YǨϥΪ̨ϥ at ܡANӨϥΪ̪bgJ /etc/at.deny YiI @ӱbg@C

ڹB@@u@Ƶ{

@u@Ƶ{iNϥ at oӫOoIoӫOB@D`²IN at [W@ӮɶYiI򥻪ykpUG

[root@www ~]# at [-mldv] TIME
[root@www ~]# at -c u@X
ﶵPѼơG
-m  G at u@AYϨSXTAH email qϥΪ̸Ӥu@wC
-l  Gat -l ۷ atqACXثetΤWҦӨϥΪ̪ at Ƶ{F
-d  Gat -d ۷ atrm AiH@Ӧb at Ƶ{u@F
-v  GiHϥθ㪺ɶ榡CX at Ƶ{u@CF
-c  GiHCX᭱Ӷu@ګOeC

TIMEGɶ榡Ao̥iHwqXyɭԭni at ou@zɶA榡G
  HH:MM				ex> 04:00
	b骺 HH:MM ɨiAYӮɨwWLAhѪ HH:MM i榹u@C
  HH:MM YYYY-MM-DD		ex> 04:00 2009-03-17
	jWwbY~Y몺Y@ѪSɨiӤu@I
  HH:MM[am|pm] [Month] [Date]	ex> 04pm March 17
	]O@ˡAjbY~YY骺YɨiI
  HH:MM[am|pm] + number [minutes|hours|days|weeks]
	ex> now + 5 minutes	ex> 04pm + 3 days
	NOAbYӮɶIyA[XӮɶz~iC

ѹ껡Ao at OUF̭nabyɶzwFIwϥΡy now + ... z 觋өwq{bLh֮ɶAiu@Aɤ]ݭnwqSwɶIӶiIUdҥݬoI

dҤ@GALAN /root/.bashrc H root ۤv
[root@www ~]# at now + 5 minutes  <==Oon[ s I
at> /bin/mail root -s "testing at job" < /root/.bashrc
at> <EOT>   <==o̿J [ctrl] + d N|X{ <EOF> rˡINI
job 4 at 2009-03-14 15:38
# WoTbA 4  at u@Nb 2009/03/14  15:38 iI
# Ӱ at |iJҿת at shell ҡAAUFhOݹB@I

dҤGGNWz 4 u@eCXӬd\
[root@www ~]# at -c 4
#!/bin/sh               <==NOzL bash shell աI
# atrun uid=0 gid=0
# mail     root 0
umask 22
....(ٲ\hܼƶ)....
cd /root || {           <==iHݥXA|UF at ɪu@ؿhO
         echo 'Execution directory inaccessible' >&2
         exit 1
}

/bin/mail root -s "testing at job" < /root/.bashrc
# AiHݨO檺ؿ (/root)A٦hܼƻPڪOeաI

dҤTGѩйwp 2009/03/18 qAڷQnb 2009/03/17 23:00 H
[root@www ~]# at 23:00 2009-03-17
at> /bin/sync
at> /bin/sync
at> /sbin/shutdown -h now
at> <EOT>
job 5 at 2009-03-17 23:00
# z@@I at ٥iHb@Ӥu@JhӫOOIaI

ǪBͷ|ƱyڭnbYYɨAbڪ׺ݾܥX Hello rˡzAMNb at ̭UFo˪Ty echo "Hello" zCɶFAoo{STbùWܡAoOԣ]ڡHoO] at P׺ݾҵLAөҦ standard output/standard error output |ǰe̪ mailbox hաIҥHb׺ݾMݤTCHSYA iHzL׺ݾ˸mӳBzIpAb tty1 nJAhiHϥΡy echo "Hello" > /dev/tty1 zӨNC

n`NOApGb at shell OèS󪺰TXA at w]|o email ̪C pGAQn at Lצp󳣵o@ email iAO_FOAiHϥΡy at -m ɶ榡 zӤUFOI at N|ǰe@ӰT̡AӤ׸ӫO榳LTXFI

at t~@ӫܴΪuIANOyIz\FIOIڡHAѶܡHP bash nohup (ĤQC) աI ڦۤvXӨҤlӵzťťAzNAFI

u~u@G즸Ĳ Unix On]Ů~ҦA O@ؤj{Aoӵ{bɪw驳U]A@Ӯרҭn] 3 ѡIѩ󳾭]niLsu@A]``ϥ Windows 98 ӳsu Unix u@] 3 ѪרҡIGA]ӪDA Windows 98 s}TѦӤvOܧC@_@ ӷɡAҦb Windows Wsu|_I]Ab]ӵ{]_FATYN]{A ѩ`ڤSo] 3 ѡI
t@ӱ`ΪɨhOҦpWdҤTAѩYӬopɭPAniYu@ɡAo at NܦnΰաI

ѩ at u@Ƶ{ϥΤWAtη|NӶ at u@WߥXA bash ҤA 浃tΪ atd {ӱޡA]AAUFF at u@NiHߨuFA ѤUu@N浃 Linux ޲zYiIҥHoApGɶu@ɡAKKI ϥ at iHAK_u᪺xZI ^_^

at u@޲z

U@ڤUFF at A~o{OJ~AӦpOnHNNLڡIQ atq P atrm aI

[root@www ~]# atq
[root@www ~]# atrm (jobnumber)

dҤ@GdߥثeDWh֪ at u@Ƶ{H
[root@www ~]# atq
5       2009-03-17 23:00 a root
# WOGyb 2009/03/17  23:00 @u@AӶu@OUF̬ 
# rootzӥBAӶu@u@X (jobnumber)  5 I

dҤGGNWz 5 Ӥu@I
[root@www ~]# atrm 5
[root@www ~]# atq
# STAܸӤu@QFI

p@ӡAAiHQ atq ӬdߡAQ atrm ӧR~OAQ at ӪUF@u@Ƶ{I²aI LAӰDݭnBz@UCpGAOb@ӫD`LtΤUB@ at A णwAu@btθɭԤ~iOHiHANϥ batch OaI

batchGtΦŮɤ~iI

batch OQ at ӶiOUFաIuO[J@ǱѼƦӤwCo batch _abGL|b CPU u@tp 0.8 ɭԡA~iAҤUFu@աI Ot 0.8 OHoӭtNOG CPU b@ɶIҭtdu@ƶqCO CPU ϥβvI |ҨӻApGڦ@{Lݭn@ϥ CPU B\A򦹮 CPU ϥβviF 100% A O CPU u@thOͪy 1 zA] CPU ȭtd@Ӥu@IpGPɰo˪{OH CPU ϥβv٬O 100% AOu@thܦ 2 FIAѥGH

ҥH]NOA CPU u@tVjAN CPU nbPu@iWcu@C o˪ CPU B@pڭ̦bĹs͹LAѰOܽЦ^h@@I]@u@AҥH|ɭPtΦLڡI tΦpGܦLA٭nB~i at AӦXzIҥH~ batch O͡I

batch pUFOOH²ڡIP at ۦPաIҦpUdҡG

dҤ@GPˬOаqb 2009/3/17 23:00 AYɨtέtӰAhȽw
[root@www ~]# batch 23:00 2009-3-17
at> sync
at> sync
at> shutdown -h now
at> <EOT>
job 6 at 2009-03-17 23:00

[root@www ~]# atq
6       2009-03-17 23:00 b root
[root@www ~]# atrm 6

A|o{ batch ]Oϥ atq/atrm Ӻ޲zIoAѥGH

۹ at OȰ@u@A`檺Ҧʤu@Ƶ{hO cron (crond) oӨtΪAȨӱC͹L Linux tΤW쥻ND`hҦʤu@A]oӨtΪAȬOw]ҰʪCt~A ѩϥΪ̦ۤv]iHiҦʤu@Ƶ{AҥHoA Linux ]ѨϥΪ̱Ҧʤu@Ƶ{O (crontab)C Uڭ̤OӲ@oI

ϥΪ̪]w

ϥΪ̷Qnإߴ`u@Ƶ{ɡAϥΪO crontab oӫOա㤣LAFwʪDA P at P˪Aڭ̥iHϥ crontab ϥΪ̱bIϥΪƦG

/etc/cron.allowG
NiHϥ crontab bgJ𫟺AYboɮפϥΪ̫hiϥ crontabF
/etc/cron.denyG
NiHϥ crontab bgJ𫟺AYOoɮ׷ϥΪ̡ANiHϥ crontab C

P at ܹaIP˪AHuǨӻA /etc/cron.allow /etc/cron.deny nuA ӧP_WAoɮץuܤ@ӨӭӤwA]AĳAunOd@ӧYiA KovTۤvb]wWP_I@ӻAtιw]OOd /etc/cron.deny A AiHNQL crontab ӨϥΪ̼gJ /etc/cron.deny A@ӱb@I

ϥΪ̨ϥ crontab oӫOӫإߤu@Ƶ{AӶu@N|Q /var/spool/cron/ ̭hFAӥBOHbӧ@POI|ҨӻA dmtsai ϥ crontab A Lu@|Q /var/spool/cron/dmtsai YhIЪ`NAnϥ vi sɮסA ]iѩJyk~A|ɭPLk cron It~A cron 檺C@u@|Q /var/log/cron oӵnɤAҥHoApGA Linux D_QӤJ차ɡA]iHjM@U /var/log/cron oӵnɩOI

nFAڭ̴NӲ@ crontab ykaI

[root@www ~]# crontab [-u username] [-l|-e|-r]
ﶵPѼơG
-u  Gu root ~ioӥȡAYLϥΪ̫إ/ crontab u@Ƶ{F
-e  Gs crontab u@e
-l  Gd\ crontab u@e
-r  GҦ crontab u@eAYȭn@AХ -e hsC

dҤ@G dmtsai bCѪ 12:00 oHۤv
[dmtsai@www ~]$ crontab -e
# ɷ|iJ vi sezsu@I`NACu@O@C
0   12  *  *  * mail dmtsai -s "at 12:00" < /home/dmtsai/.bashrc
#    g |<==============O========================>|

w]pUAϥΪ̥unQCJ /etc/cron.deny ALNiHUFy crontab -e zhsۤvҦʩROFIӹL{NpPW쪺A|iJ vi seA MH@Ӥu@@ӽsAs觹Jy :wq zxs} vi NiHFI ӨCu@ (C) 榡O㦳Ao쪺NqG

NNq		p			g	O
Ʀrd	0-59	0-23	1-31	1-12	0-7	rNO

쪺OӡygzIgƦr 0 7 ɡANyPѡzNIt~A ٦@ǻUršAjUoǡG

Sr	NNq
*(P)	Nɨ卖NI\|ҨӻAdҤ@ӤBBgO * A NNۡyצB骺§X 12:00 OzNI
,(r)	NjɬqNC\|ҨӻApGnUFu@O 3:00 P 6:00 ɡAN\|OG 0 3,6 * * * command ɶѼ٬OALĤGO 3,6 AN 3 P 6 AΡI
-()	N@qɶd򤺡A\|ҨӻA 8 I 12 ICpɪ 20 i@u@G 20 8-12 * * * command JӬݨĤGܦ 8-12 IN 8,9,10,11,12 AΪNI
/n(׽u)	n NƦrAYOyCj n 춡jzNAҦpCi@AhG /5 * * * command ²aI * P /5 ӷftA]iHg 0-59/5 AۦPNI

ڭ̴NӷftXӨҤlm߬ݬݧaIUרҽйڥ dmtsai oӨ@ݬݳI򪺰ʧ@~ft_ӡI

DG

YAkBͥͤO 5 2 AAQnb 5 1 骺 23:59 o@ʫHLAoʫHewggb /home/dmtsai/lover.txt FAӦpiH

G

UF crontab -e As覨G

59 23 1 5 * mail kiki < /home/dmtsai/lover.txt

˪ܡAC~ kiki |AoʫHI]MoAHeNnC~ܤ@ܰաI^

DG

pCݭn /home/dmtsai/test.sh @ASӦpH

G

P˨ϥ crontab -e iJsG

*/5 * * * * /home/dmtsai/test.sh

crontab CӤHu@ɮצsbANOb /var/spool/cron ̭ڡI ٦ĳzGyOUFɡA̦nϥε|Aoˤ|䤣ɳIz

DG

pACPPBͦAQnCӬPU 4:30 iDABͬP|nѰOAhG

G

٬Oϥ crontab -e ڡI

30 16 * * 5 mail friend@his.server.name < /home/dmtsai/friend.txt

uO²aIIAӦpdߨϥΪ̥ثe crontab eOHڭ̥iHo˨ӬݬݡG

[dmtsai@www ~]$ crontab -l
59 23 1 5 * mail kiki < /home/dmtsai/lover.txt
*/5 * * * * /home/dmtsai/test.sh
30 16 * * 5 mail friend@his.server.name < /home/dmtsai/friend.txt

# `NAYȷQn@u@ӤwܡAn crontab -e hs
# pGQnu@A~ϥ crontab -r I
[dmtsai@www ~]$ crontab -r
[dmtsai@www ~]$ crontab -l
no crontab for dmtsai

ݨFܡH crontab yӤeFIzҥHЪ`NGypGuOnRY crontab u@ءAШϥ crontab -e ӭssYiIzpGϥ -r ѼơAO|NҦ crontab ƤeRIdU`NFI

tΪ]wɡG /etc/crontab

oӡy crontab -e zOwϥΪ̪ cron ӳ]pApGOytΪҦʥȡzɡA ӫOHO_٬OݭnH crontab -e Ӻ޲zAҦʤu@Ƶ{OHMݭnAAuns /etc/crontab oɮ״NiHաI@IݭnSO`NINO crontab -e o crontab O /usr/bin/crontab oӰɡAO /etc/crontab iO@ӡy¤rɡzIAiH root s@Uoɮ׭I

򥻤WA cron oӪAȪ̧COyzAҥHy cron |ChŪ@ /etc/crontab P /var/spool/cron ̭Ƥe zA]AunAs觹 /etc/crontab oɮסAåBNLxsA cron ]wN۰ʪ|ӰFI

b Linux U crontab |۰ʪڭ̨CsŪ@ /etc/crontab Ҧu@ƶAOYǭ]Ϊ̬OL Unix tΤAѩ crontab OŪOAҥHbAק粒 /etc/crontab Aiä|WA oӮɭԽЭsҰ crond oӪAȧaIy/etc/init.d/crond restartz

oܤֻAڭ̴NӬݤ@Uo /etc/crontab eaI

[root@www ~]# cat /etc/crontab
SHELL=/bin/bash                     <==ϥέ shell 
PATH=/sbin:/bin:/usr/sbin:/usr/bin  <==ɷjM|
MAILTO=root                         <==YB~STDOUTAH emailNưe
HOME=/                              <==w] shell aؿҦb

# run-parts
01  *  *  *  *   root      run-parts /etc/cron.hourly   <==Cp
02  4  *  *  *   root      run-parts /etc/cron.daily    <==C
22  4  *  *  0   root      run-parts /etc/cron.weekly   <==Cg
42  4  1  *  *   root      run-parts /etc/cron.monthly  <==CӤ 1 
    g ̨  O

ݨoɮתeAjNAѤFaIASIoɮ׻PNڭ̤UF crontab -e eXG@Ҥ@ˡIuOXӦa褣ӬۦPG

MAILTO=rootG

oӶجOA /etc/crontab oɮפҦʤu@OoͿ~ɡAΪ̬OӤu@浲G STDOUT/STDERR ɡA|N~TΪ̬OùܪTǵ֡Hw]MOѨtΪHo@ mail root աILA ѩ root õLkbΤݤH POP3 n马HA]Aq`No e-mail 令ۤvbAnHAѨtΪpIҦpG MAILTO=dmtsai@my.host.name
PATH=....G

ٰOoڭ̦bĤQ@ BASH @쪺ɸ|DaI SաIo̴NOJɪjM|Iϥιw]|]wNwgܨFI
01 * * * * root run-parts /etc/cron.hourlyG

o /etc/crontab ̭w]wqX|u@ȡAOOCpɡBCѡBCgΨCӤOi@u@I Ob᭱äOOAӬO@ӷsANOy᭱OzIoPϥΪ̪ crontab -e ۦPCѩϥΪ̦ۤv crontab äݭnwA /etc/crontab ̭MnwաIHWeӻAtιw]Ҧʤu@OH root Ӷi檺C

᭱OOOHAiHϥΡy which run-parts zjMݬݡA꨺O@ bash script աIpGAiJ /usr/bin/run-parts hݬݡA |o{oO|N᭱yؿzҦɮ׮XӰIo]NOy pGAQtΨCpɥDAYӫOANӫOg scriptAñNɮשm /etc/cron.hourly/ ؿUYizNI

{bADtάOpiLw]@Ҧʤu@Ƶ{FܡHpGAUFy ll /etc/cron.daily zNiHݨ@ɮסA ɮ״NOtδѪ script Aӳo scripts N|bCѪ 4:02 }lB@Io]OԣpGAO]߱ڡA N|o{_ǪOALinux tά󦭤W 4:02 }l|ܦLoX@ǵwж]ʪnI]Lni makewhatis, updatedb, rpm rebuild ȹI

ѩ CentOS Ѫ run-parts o script UA] /etc/crontab oɮ׸̭䴩ؤUFO觋A @جOUFOA@ثhOHؿӳWAҦpG

OA
01 * * * * dmtsai mail -s "testing" kiki < /home/dmtsai/test.txt
H dmtsai oӨϥΪ̪AbCpɰ@ mail OC
ؿW
*/5 * * * * root run-parts /root/runcron
إߤ@ /root/runcron ؿANnCj檺yiɡzgӥؿUA NiHtΨC@ӥؿUҦiɡC

nIA{bjAѤFo@өNNaIOKI]A{bn@@ӥؿAtΥiHC 2 hoӥؿUҦiH檺ɮסAAiHgUpUo@b /etc/crontab G

*/2 * * * * root run-parts /etc/cron.min

MoA /etc/cron.min oӥؿOݭnsbIpGڻݭn檺O@ӡy{zӤwA ݭnΨ@ӥؿOHӦpOnHҦpbyqɡAڭ̧ƱCR@A iHo˼gG

*/5 * * * * root /bin/mrtg /etc/mrtg/mrtg.cfg

pIإߨҦʩRO²aIpGAOtκ޲zӥBAu@SOtκ@譱ҦȮɡA ק /etc/crontab oɮקYiISKQASK޲zOI

@Ǫ`Nƶ

귽tD

jqϥ crontab ɭԡA`O|DoͪAYDNOytθ귽tzDA HtάҡAڦDyqTA]AG

yq
ϰ줺L PC yq
CPU ϥβv
RAM ϥβv
uWHƧYɰ

pGCӬy{bP@ӮɶҰʪܡAbYӮɬqɡAڪtη|ܪ۷cA ҥHAoӮɭԴNnO]wաIڥiHo˰G

[root@www ~]# vi /etc/crontab
1,6,11,16,21,26,31,36,41,46,51,56 * * * * root  CMD1
2,7,12,17,22,27,32,37,42,47,52,57 * * * * root  CMD2
3,8,13,18,23,28,33,38,43,48,53,58 * * * * root  CMD3
4,9,14,19,24,29,34,39,44,49,54,59 * * * * root  CMD4

ݨFSHӡy , zjɭԡAЪ`NAnťզrI]s򪺷N^p@ӡA hiHNCu@y{ObPɨӤu@IhiHtΪZI

nX

t~@ӧxZoͦby 榨GΪ̬O檺ؤXƮɡAӸƱN| mail MAILTO ]wb zAnաA@ӱƵ{@X]Ҧp DNS tηAY DNS WhDAAN|@~TI^HIٰOoQ@ͨ쪺ƬyɦVaH HyROɦVzNXGX /dev/null oөUNnFI

w

ܦhɭԳQӤJ차OHҦRO觋ӤJAҥHiHǥˬd /var/log/cron eӵO_yDz]w cron QFHzoӮɭԴNݭnpߤ@IoI

gP뤣iPɨæs

t@ӻݭn`NabGyAiHOHgΪ̬O묰@`AAiϥΡuXXBPXvҦu@zC oӷNOAAiHo˽sg@Ӥu@Ƶ{G

30 12 11 9 5 root echo "just test"   <==oO~gk

ӧAHEQ@BP~|iou@AL`OAtΥi|PwCӬP@@AΨC~ 9 11 OiAp@ӻPA쪺WN@ˤFҥHoAon`NoӦaIWzgkO諸I

pGA Linux DO@ 24 pɥѡB~L𪺦AΡAAun atd P crond oӪAȨӺ޲zAҦʤu@Ƶ{YiCpGAAëD 24 pɵL_}AAӦpiҦʤu@H |ҨӻApGACѱߤWnAդѤ~ҰʧA Linux DɡAѩ CentOS w]u@Ƶ{b 4:02am CѶiAIp@ӤN@tΨҦu@SHbFIiHɴNon anacron oåFI

O anacron

anacron äOΨӨN crontab Aanacron sbتNbڭ̤WY쪺AbBzD 24 pɤ@Ұʪ Linux tΪ crontab IҥH anacron äwɰYȡA ӬOHѬΪ̬Ob}ߨi anacron ʧ@AL|hӶiOèSi檺 crontab ȡAñNӥȰ@MAanacron N|۰ʰFC

ѩ anacron |H@ѡBCѡB@Ӥ묰htΥi檺 crontab ȡA]YǯSϥҫD`UC |ҨӻApGA Linux DObqPϥΪA]gjabҥH]Sn}ҡA ]A Linux Og|ѪCO crontab jhbCѪHζg骺WiUȡA ASFAɨtΫܦh crontab ȴNLkiC anacron niHѨMoӰDI

anacron SO򪾹Dڭ̪tԣOHoNonϥ anacron ŪɶO (timestamps) FI anacron |hR{bɶPɶOɩҰOW anacron ɶA̤Yo{tA NObYǮɨSi crontab oI anacron N|}l楼i檺 crontab ȤFI ҥH anacron ]OzL crontab ӹB@I] anacron B@ɶq`ӡA@ӬOtζ}B@A@ӬOgJ crontab Ƶ{C oˤ~bSwɶRtΥi檺 crontab u@IAѥGI

anacron P /etc/anacrontab

anacron O@{ëD@ӪAȡIo{b CentOS wgiJ crontab Ƶ{I ۫HܡHAiHo˰lܬݬݡG

[root@www ~]# ll /etc/cron*/*ana*
-rwxr-xr-x 1 root root 379 Mar 28  2007 /etc/cron.daily/0anacron
-rwxr-xr-x 1 root root 381 Mar 28  2007 /etc/cron.monthly/0anacron
-rwxr-xr-x 1 root root 380 Mar 28  2007 /etc/cron.weekly/0anacron
# nOCѡBCgBC릳Ƶ{u@ؿId\@UCѪ

[root@www ~]# cat /etc/cron.daily/0anacron
if [ ! -e /var/run/anacron.pid ]; then
    anacron -u cron.daily
fi
# ҥH]ȬO anacron -u OI]ڭ̱oӽͽͳo{I

򥻤WA anacron ykpUG

[root@www ~]# anacron [-sfn] [job]..
[root@www ~]# anacron -u [job]..
ﶵPѼơG
-s  G}l@s򪺰Uu@ (job)A|̾ڮɶOɪƧP_O_iF
-f  GjiAӤhP_ɶOɪɶWOF
-n  Gߨi楼i檺ȡAӤ (delay) ݮɶF
-u  GȧsɶOɪɶWOAiu@C
job G /etc/anacrontab wqUu@W١C

ҥHڭ̵o{ /etc/cron.daily/0anacron ȶiɶWOsAӨSi anacron ʧ@I bڭ̪ CentOS Aanacron iOb}~i檺@u@ȡAA]iHN anacron ƤJ crontab Ƶ{COF anacron ~PɶѼơA] /etc/cron.daily/ ̭ anacron ~|bɦWe[ 0 (0anacron)A anacron ̥iINOFɶWOsIHקK anacron ~P crontab |iu@NC

Uӧڭ̬ݤ@U /etc/anacrontab enFG

[root@www ~]# cat /etc/anacrontab
SHELL=/bin/sh
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root

1       65      cron.daily     run-parts /etc/cron.daily
7       70      cron.weekly    run-parts /etc/cron.weekly
30      75      cron.monthly   run-parts /etc/cron.monthly
Ѽ   ɶ u@W٩wq   ڭni檺O
# ѼƳ쬰ѡFɶ쬰Fu@W٩wqiۭqF
# Ohq`P crontab ]wۦPI

[root@www ~]# more /var/spool/anacron/*
::::::::::::::
/var/spool/anacron/cron.daily
::::::::::::::
20090315
::::::::::::::
/var/spool/anacron/cron.monthly
::::::::::::::
20090301
::::::::::::::
/var/spool/anacron/cron.weekly
::::::::::::::
20090315
# WhOTӤu@W٪ɶOɥHΰOɶWO

ѩ /etc/cron.daily ȤhA]ڭ̨ϥΨCѶi檺ȨӸ@U anacron B@pnFC anacron YUFy anacron -s cron.daily zɡAL|o˹B@G

/etc/anacrontab R cron.daily ou@W٪ѼƬ 1 ѡF
/var/spool/anacron/cron.daily X̪@ anacron ɶWOF
ѤWӨBJPثeɶAYtѼƬ 1 ѥHW (t 1 )ANǳƶiOF
YǳƶiOAھ /etc/anacrontab ]wAN 65
ɶLA}lOAYy run-parts /etc/cron.daily zoOF
槹A anacron {C

ҥHAɶWOOD`nIanacron OzLӰOPثeɶtAAѨO_ӭniYȪu@I |ҨӻApGڪDb 2009/03/15(P) 18:00 AMb 2009/03/16(P@) 8:00 }Aѩڪ crontab ObW 04:00 kiUȡAѩӮɨtάOA]ɶWO¬ 20090315 (ªɶ)A OثeɶwgO 20090316 (sɶ)A] run-parts /etc/cron.daily N|b}L 65 }lB@FC

ҥHoA anacron äݭnB~]wAϥιw]ȧYiIuOڭ̪ CentOS ub}ɤ~| anacron NOFCpGnTw anacron O_}ɷ|DʪAAiHUFUCOG

[root@www ~]# chkconfig --list anacron
anacron      0:off   1:off   2:on    3:on    4:on    5:on    6:off
# ԲӪ chkconfig ڭ̷|b򳹸`A`N 3, 5
# ءAO on INOҰʰաI}ɤ~|檺NI

{bADjF@}l~N CentOS }A}L 1 pɥktη|@pqɶLIӥBwз|]ӤINO] anacron bLh crontab i檺Uu@Ƶ{աIo˹ anacron SFOH ^_^

tΥiHzL at oӫOӱƵ{@u@ȡIyat TIMEzOUFkA at iJƵ{A tΰӱƵ{u@ɡA|UFɪؿiȡF
at 楲n atd AȪ䴩AB /etc/at.deny O_檺ϥΪ̱bF
zL atq, atrm iHd߻PR at u@Ƶ{F
batch P at ۦPAL batch ib CPU u@tp 0.8 ɤ~i򪺤u@Ƶ{F
tΪ`Ҧʤu@Ƶ{ϥ cron oӪAȡAPɧQ crontab -e /etc/crontab iƵ{wơF
crontab -e ]wؤAyBɡBBBPBOz]w̾ڡF
/etc/crontab ]wCAyBɡBBBPB̡BOz]w̾ڡF
anacron tX /etc/anacrontab ]wAiHtΥi檺 crontab ȡI

²DG

Ѱ]ڦ@ӫO{AW٬G ping.sh oɦWIڷQntΨCToɮפ@A Ooɮ׷|ܦhTܥXӡAҥHڪ root bCѳ|th|ʦhʪHAOHNth֭nƱFI аӫ]wnOH
oӯAθƬyɦVDAڭ̥iHNLɤJɮשΪ̪IpGӰTnܡA NHApGTܭnܡA~NLOdUӡI]ѳoөROnA ҥHNL󱼡I]AiHo˼gG
*/3 * * * * root /usr/local/ping.sh > /dev/null 2>&1
zwpnb 2010 ~ 2 14 HX@ʵ kiki AuӦ~~HXIӦpUFOH
at 1am 2010-02-14
UF crontab -e ApGJo@ANNH
* 15 * * 1-5 /usr/local/bin/tea_time.sh
bCP 1~5 AU 3 ICA@i 60 /usr/local/bin/tea_time.sh oɮסC nSO`NOACӬP 1~5 3 I|i 60 Iܳ·ЧaO~gkա ӬOngG
30 15 * * 1-5 /usr/local/bin/tea_time.sh
ڥ vi s /etc/crontab oɮסAڽs𫍧@Oo˪G
25 00 * * 0 /usr/local/bin/backup.sh
o@NNqOH
o@N......SNqI]yk~IznAѡAb /etc/crontab C@泣nϥΪ̤~IҥHAӭnN쥻令G
25 00 * * 0 root /usr/local/bin/backup.sh
аݡAztΨCѡBCgBCӤUi椰u@H
] CentOS tιw]ҦʩROmb /etc/cron.* ̭AҥHAAiHۦhG /etc/cron.daily/, /etc/cron.week/, /etc/cron.monthly/ oTӥؿݤ@ݡA NDաI ^_^
CӬPTIhtηjM@U SUID/SGID ɮסIñNGX /tmp/uidgid.files
vi /etc/crontab
0 3 * * 6 root find / -perm +6000 > /tmp/uidgid.files