在配置 RAC 过程用到。OS：Linux 2.6.9-42.ELsmp #1 SMP Sat Aug 12 09:39:11 CDT 2006 i686 i686 i386 GNU/Linux 　

节点1上的配置：
more /etc/ntp.conf
restrict default ignore
restrict 192.168.0.0 mask 255.255.255.0 notrap nomodify
server 162.105.129.27 # 互联网上的时间服务器
server 127.127.1.0 # local clock
fudge 127.127.1.0 stratum 10
driftfile /var/lib/ntp/drift
broadcastdelay 0.008
keys /etc/ntp/keys


节点2上的配置：
more /etc/ntp.conf

restrict default ignore
restrict 127.0.0.1
restrict 192.168.0.0 mask 255.255.255.0 nomodify
server 192.168.0.125 # 以节点1作为上级时间服务器
restrict 192.168.0.125
driftfile /var/lib/ntp/drift
broadcastdelay 0.008
keys /etc/ntp/keys


在两个节点上分别运行：
service ntpd start
chkconfig --level 35 ntpd on


参考：
http://publish.it168.com/2007/0417/20070417003602.shtml
http://bbs.chinaunix.net/viewthread.php?tid=931263