Linux system download and install Network Time Protocol NTP pack

Network Time Protocol (NTP) is a protocol that is used to help the Linux system clock synchronize with the exact time source. Allows all sites on the web to be synchronized. Divided into two categories:

* Class 1th: The atomic clocks used by the NTP site are timed.
* Class 2nd: NTP sites and smaller exact time sources. (NTP sites with slightly pager accurate time sources)

The advantage of this approach is that at least one server becomes a local time server on your network, serving other devices. (This makes the correlation of system http://www.aliyun.com/zixun/aggregation/38907.html ">events on different Bae Much easie this makes it easy to correlate system event dependencies on different systems. It also reduces the amount of Internet bandwidth used due to NTP communications and reduces firewall rules for each NTP client. And not all servers will have Internet access. In this case, you need a central server to handle all access.

Most versions of Redhat and Fedora Linux software products can be in RPM format. Downloading and installing from RPMs is not difficult.

When looking for the file, remember that the NTP RPMs filename is usually in the NTP version number, such as: ntp-4.1.2-5.i386.rpm

/etc/ntp.conf file

The/etc/ntp.conf file is the primary configuration file for Linux NTP, and you can set the IP address of the NTP server. Here are the steps to establish an Internet based NTP server

1 Specify an interested server first:

2 Limit the types of access you allow to these servers, in this case the server is not allowed to modify the runtime configuration or query your Linux NTP server:

The Mask 255.255.255.255 statement is really a subnet mask limiting access to the the remote NTP servers.

3 If this server is also to provide time to other computers, such as PCs, other Linux servers and network devices, you must define the network's request to accept NTP synchronization from this server. You need to modify the Restric statement, remove the Noquery keyword, and let the network query your NTP server. The syntax is:

In this case, mask includes all 255 possible IP addresses within the local network.

4 also make sure that localhost (this commonly used IP address is used to refer to the Linux server itself) has sufficient permissions. Use syntax with no restricted keywords:

5 Save the file and restart NTP for these settings to take effect. Now you can set up other Linux hosts on your network to sync with this new primary NTP server in a similar way.