Design and implementation of real-time file synchronization scheme between two servers under Linux

Original address http://blog.csdn.net/5iasp/article/details/13630927

Design and implementation of real-time file synchronization scheme for two servers under Linux

Assume the following requirements:

Assume two servers:

192.168.0.1 The source server has the directory /opt/test/

192.168.0.2 The target server has the directory /opt/bak/test/

The purpose of implementation is to keep a certain file directory of the two servers synchronized in real time

Implementation method: Implemented through the combination of rsync+inotify-tools

Need to install software:

1. rsync synchronization software

Need to be installed on both the source server and the target server

Source server: It is an rsync client, not Need to configure

Target server: It is the rsync server and needs to configure the contents in /etc/rsyncd.conf

After installation, you need to create a new configuration file: /etc/rsyncd.conf

The configuration file is in: /etc/

The content of the file is as follows:

uid = root
gid = root
use chroot = no
max connections = 10
strict modes = yes
pid file=/var/run/rsyncd.pid
lock file=/var/run/ rsyncd.lock
log file= =/var/run/rsyncd.log

[www]
path= /opt/bak/test
comment= analyze
read only = false
hosts allow = *

2 . inotify-tools tool

This tool is a real-time file monitoring tool that requires Linux operating system kernel support. Kernel support requires at least version 2.6.13

Check whether the operating system supports it. Execute as follows:

uname -r View version

Return:

2.6.32-220.4.1.el6.x86_64

means that version 2.6.32 is greater than 2.6.13, so it is supported.

Execution:

ll /proc/sys/fs/inotify
total 0
-rw-r--r-- 1 root root 0 Oct 18 12:18 max_queued_events
-rw-r--r-- 1 root root 0 Oct 18 12:18 max_user_instances
-rw-r--r-- 1 root root 0 Oct 18 12:18 max_user_watches

There are three outputs, which means inotify is supported by default and the inotify-tools tool can be installed.

If it is not supported, you need to use a new version of the Linux operating system. If the version meets the requirements, it can be installed.

After installing inotify-tools, the following two files will be generated in the relevant installation directory:

ll /usr/local/bin/

-rwxr-xr-x 1 root root 44327 Oct 10 15:32 inotifywait
-rwxr-xr-x 1 root root 41417 Oct 10 15:32 inotifywatch

means the installation is successful.

inotify_bak.sh

#!/bin/bash

/usr/local/bin/inotifywait -mrq --timefmt '%d/%m/%y %H:%M' --format '%T %w%f%e' -e close_write,delete,create,attrib $src | while read file
do

/usr/bin/rsync -arzuq $src 192.168.0.2::www/

echo " ${file} was rsynced" >>/opt/soft/log/rsync.log 2>&1

Note : The www here is the module name configured in the target server/etc/rsyncd.conf: [www]

Give execution permissions: chmod +x inotify_bak.sh

Then execute: inotify_bak.sh & Put it in the background for execution

4. About starting

Target server: Start the rsync background service first: /usr/bin/rsync --daemon

Source server: Execute inotify_bak.sh &

Create a new directory in the source server directory and files, the inotify_bak.sh script will detect it and synchronize it to the relevant directory of the target server

tail -f /opt/soft/log/rsync.log

The above introduces the design and implementation of the real-time synchronization scheme of files between two servers under Linux, including various aspects. I hope it will be helpful to friends who are interested in PHP tutorials.