环境
软件：fedora14，装在virtualbox虚拟机上
硬件：x86具体步骤
检查是否安装了ntp
运行如下命令：
rpm -qa | grep ntp
如果有如下输出，表示有安装ntp 服务器
ntp-4********
如果有如下输出，表示有安装ntp客户端
ntpdate-******
如果没有安装，执行 yum -y install ntp
修改ntp的配置文件
用文件ntp.conf替换掉/etc/ntp.conf文件，ntp.conf内容如下
# For more information about this file, see the man pages # ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_misc(5), ntp_mon(5). driftfile /var/lib/ntp/drift # Permit time synchronization with our time source, but do not # permit the source to query or modify the service on this system. # rongp comment #restrict default kod nomodify notrap nopeer noquery #restrict -6 default kod nomodify notrap nopeer noquery restrict 192.168.1.94 restrict 192.168.1.0 mask 255.255.255.0 nomodify # Permit all access over the loopback interface. This could # be tightened as well, but to do so would effect some of # the administrative functions. # rongp comment # restrict 127.0.0.1 # restrict -6 ::1 # Hosts on local network are less restricted. #restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap server ntp.amnic.net prefer server time.windows.com prefer server time-nw.nist.gov prefer server time.nist.gov prefer restrict ntp.amnic.net restrict time.windows.com restrict time-nw.nist.gov restrict time.nist.gov prefer # Use public servers from the pool.ntp.org project. # Please consider joining the pool (http://www.pool.ntp.org/join.html). # rongp comment # server 0.fedora.pool.ntp.org iburst # server 1.fedora.pool.ntp.org iburst # server 2.fedora.pool.ntp.org iburst # server 3.fedora.pool.ntp.org iburst #broadcast 192.168.1.255 autokey # broadcast server #broadcastclient # broadcast client #broadcast 224.0.1.1 autokey # multicast server #multicastclient 224.0.1.1 # multicast client #manycastserver 239.255.254.254 # manycast server #manycastclient 239.255.254.254 autokey # manycast client # Undisciplined Local Clock. This is a fake driver intended for backup # and when no outside source of synchronized time is available. server 127.127.1.0 # local clock fudge 127.127.1.0 stratum 10 # Enable public key cryptography. #crypto includefile /etc/ntp/crypto/pw # Key file containing the keys and key identifiers used when operating # with symmetric key cryptography. keys /etc/ntp/keys # Specify the key identifiers which are trusted. #trustedkey 4 8 42 # Specify the key identifier to use with the ntpdc utility. #requestkey 8 # Specify the key identifier to use with the ntpq utility. #controlkey 8 # Enable writing of statistics records. #statistics clockstats cryptostats loopstats peerstats
重启ntp服务器
执行命令： service ntpd restart
检查是否正常开启ntp服务器
执行命令： ps -ef | grep ntpd | grep -v grep
如果有输出表示已开启，然后用客户端进一步测试能否正常同步到该ntp服务器，用另外一台电脑（需要安装ntpdate)，执行ntpdate ntp服务器地址 eg: ntpdate 192.168.1.94
如果有如下类似输出：
28 May 17:33:39 ntpdate[29134]: step time server 192.168.1.94 offset 3.174187 sec
表示同步成功。
注意：刚开启的ntp服务器需要过几分钟后客户端才能够去同步，因为ntp服务器本身要和远程ntp服务器同步需要时间，因此可能会遇到如下出错信息：
28 May 17:32:00 ntpdate[29104]: no server suitable for synchronization found
这种情况，过几分钟后再试试，这个情况还可能是其他原因导致，这里不再描述。
附录
配置文件说明：
restrict开头的行，表示设置客户端连接到本ntp服务器的权限
server开头的行，表示设置本ntp服务器连接到远程ntp服务器的地址 server 127.127.1.0 # local clock fudge 127.127.1.0 stratum 10上面两行的意思是如果server指定的服务器连接失败，采用本地的时间来同步时间
完！
2012年6月