????????linux???????????Internet??????
???????????????
????# cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
?????????й????????
????# vi /etc/sysconfig/clock
????ZONE="Asia/Shanghai"
????UTC=false
????ARC=false
?????????????μ????
?????????趨??
????# date -s 2008/05/06
????????趨??
????# date -s 18:40:00
????????????BIOS?????
????hwclock [-rw]
????-r:??????BIOS?????????r????
????-w:???????linux?????д??BIOS??
??????????????? Linux ????У?????????? hwclock -w ?????? BIOS ??????????ο?????????????????? BIOS ????????????????? BIOS ?????????????????
????# hwclock
????Tue 06 May 2008 03:49:37 PM CST  -0.039646 seconds
???????BIOS?????????????д??CMOS??
????# clock -w
???????????Internet????????????????????????????
????????1. ????????????????У???
????vi /etc/rc.d/rc.local
????/usr/sbin/ntpdate -u 192.168.0.2 192.168.0.3 192.168.0.4;   /sbin/hwclock -w
????????2. ?趨???????
????crontab??????￡?
????# For details see man 4 crontabs
????# Example of job definition:
????# .---------------- minute (0 - 59)
????# |  .------------- hour (0 - 23)
????# |  |  .---------- day of month (1 - 31)
????# |  |  |  .------- month (1 - 12) OR jan??feb??mar??apr ...
????# |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR sun??mon??tue??wed??thu??fri??sat
????# |  |  |  |  |
????# *  *  *  *  *  command to be executed
?????趨crontab??????????????????
????1??д??/etc/crontab??
????????:
????00 11 * * * root ntpdate 210.72.145.44
???????11?????й??????????????
???????11?????й??????????????
????????????
????apt-get install ntpdate
?????????????
????00 11 * * * root ntpdate us.pool.ntp.org
????2?????????crontab -e
????crontab -e
????10 5 * * * root ntpdate us.pool.ntp.org;hwclock -w
???????????5:10???????????У???????????BIOS?????