部署ntp时间服务器

NTP（Network Time Protocol，网络时间协议）是用来使网络中的各个计算机时间同步的一种协议。时间的准确性是非常重要的，很多数据上传下载等都需要记录正确的时间。

1.检查NPT软件

[root@centos ~]# rpm -qa|grep ntpntpdate-4.2.6p5-1.el6.centos.x86_64ntp-4.2.6p5-1.el6.centos.x86_64

2.配置同步时间服务器站点

编辑NTP服务配置文件/etc/ntpd.conf，将默认的全部加上#号，重新加入国内的几个NTP站台地址

[root@centos ~]# cat /etc/ntp.conf# 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.restrict default kod nomodify notrap nopeer noqueryrestrict -6 default kod nomodify notrap nopeer noquery# Permit all access over the loopback interface.  This could# be tightened as well, but to do so would effect some of# the administrative functions.restrict 127.0.0.1restrict -6 ::1# Hosts on local network are less restricted.#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap# Use public servers from the pool.ntp.org project.# Please consider joining the pool (http://www.pool.ntp.org/join.html).#server 0.centos.pool.ntp.org iburst          //将原来的0-3四组用#号注释掉#server 1.centos.pool.ntp.org iburst#server 2.centos.pool.ntp.org iburst#server 3.centos.pool.ntp.org iburstserver ntp.sjtu.edu.cn                        //加上如下几组大学时间服务器站点，该地址可以自己修改配置server s1a.time.eud.cnserver s1b.time.eud.cnserver s1d.time.eud.cnserver s2c.time.eud.cn#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# Enable public key cryptography.#cryptoincludefile /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

3.启动NTP时间服务器

NTP服务器配置完成后，在启动NTP服务后，请等待几分钟，因为NTP时间服务器是长久运行的服务，将其设为系统默认启动

[root@centos ~]# service ntpd startStarting ntpd:                                             [  OK  ][root@centos ~]# chkconfig ntpdon

4.检查NTP服务运作的状态

[root@centos ~]# netstat -lntup|grep ntpdudp        0      0 192.168.8.205:123           0.0.0.0:*                               11458/ntpdudp        0      0 127.0.0.1:123               0.0.0.0:*                               11458/ntpdudp        0      0 0.0.0.0:123                 0.0.0.0:*                               11458/ntpdudp        0      0 fe80::a00:27ff:fe09:ad17:123 :::*                                    11458/ntpdudp        0      0 ::1:123                     :::*                                    11458/ntpdudp        0      0 :::123                      :::*                                    11458/ntpd