Install the NTP server on centos 5.6

The installation of the NTP server on centos 5.6 requires time synchronization between some services and multiple machines in the experiment. Therefore, the prerequisites for building NTP are as follows: 1. install the ntp service yum install ntp. I *-y2, modify/etc/ntp. confrestrict default kod nomodify notrap nopeer noquery # restrict-6 default kod nomodify notrap nopeer noquery # for ipv6 # This is the default ntp setting www.2cto.com # Allow all local operations restrict 127.0.0.1 restrict-6 :: 1 # allowed LAN segments restrict 10.0.0.0 mask 255.0.0.0 nomodify motraprestrict 192.168.0.0 mask 255.255.0.0 nomodify Motrap # use the upper-layer internet ntp server restrict authorization mask authorization limit 255 nomodify notrap noqueryserver limit # If the communication fails with the upper-layer ntp server, the local time is used as the standard time. server 127.127.1.0 stratum 10 # Calculation the frequency error between the ntp server and the upper ntpserver: driftfile/var/lib/ntp/drift # Key file containing the keys and key identifiers used when operating # with Your Ric key cryptography. keys/etc/ntp/keys # logs File logfile/var/log/ntp. log # Description: restrict <IP address> <subnet mask> | <network segment> <subnet mask> [ignore | noquery | notrap | nomodiy | notrust | nokod] ignore: disable all ntp services www.2cto.com noquery: No ntp service notrap: No trap remote event logon function nomodiy: indicates that the client cannot change the time parameter of the ntp server, however, you can use the ntp server to correct the time. notrust: reject the unauthenticated client nokod: kod technology can organize a dos attack 2, modify the/etc/ntp/step-tickers file 207.46.232.182127.127.1.0 # When the ntp server is started, it automatically verifies the time with the recorded ip address in this file. 3, modify/etc/sysconfig/ntpdSYNC_HWCLOCK = YES # Allow B Time synchronization between IOS and System 4 and client configuration is omitted.