rsync轻松搞定Linux下的文件同步(备份)

rsync文件同步配置

server端：主机名s170

client端：主机名s156

目录：/opt/test

用户：root

目标：配置rsync使得client端可以把server的/opt/test目录中的文件同步(备份)过来。 

操作步骤一：确认rsync是否安装

server端和client端： 

[root@s156 ~]# yum list rsync
Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
 * base: CentOS.ustc.edu.cn
 * extras: centos.ustc.edu.cn
 * updates: centos.ustc.edu.cn
Installed Packages
rsync.i386                                                                  3.0.6-4.el5_7.1                                                                   installed
[root@s156 ~]#  

如果没有安装，则使用下面的命令安装

yum install -y rsync 

操作步骤二：启动rsync服务

server端：  

[root@s170 mysql]# chkconfig rsync --list
rsync           关闭
[root@s170 mysql]# chkconfig rsync on
[root@s170 mysql]# chkconfig rsync --list
rsync           启用
[root@s170 mysql]# 

操作步骤三：设置ssh免登录

server端：  

检查server端的.ssh目录

[root@s170 ~]# cd .ssh/
[root@s170 .ssh]# ls -a
.  ..  known_hosts 

此步的目的是为了后面确认~/.ssh目录中文件的变化。 

client端：  

[root@s156 ~]# ssh-keygen -d
Generating public/private dsa key pair.
Enter file in which to save the key (/root/.ssh/id_dsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_dsa.
Your public key has been saved in /root/.ssh/id_dsa.pub.
The key fingerprint is:
0b:9d:3e:64:77:17:6a:d8:60:1e:ab:47:42:d1:8e:51 root@s156
[root@s156 ~]#

其中，/root/.ssh/id_dsa 是私钥，/root/.ssh/id_dsa.pub 是公钥。  

现在，将公钥复制到server端。

[root@s156 .ssh]# ssh-copy-id -i ~/.ssh/id_dsa.pub root@s170
21
ssh: connect to host s170 port 22: Connection refused

由于s170机器的ssh服务端口已修改，使用默认的22端口访问失败。
注意：下面的命令行中指定端口的方法。
[root@s156 .ssh]# ssh-copy-id -i ~/.ssh/id_dsa.pub "-p 21702 root@s170"
21
root@s170's password:
Now try logging into the machine, with "ssh '-p 21702 root@s170'", and check in:

  .ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.

[root@s156 .ssh]#  

server端：  

[root@s170 .ssh]# ls -a
.  ..  authorized_keys   known_hosts
[root@s170 .ssh]# cat authorized_keys
ssh-dss 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 root@s156
[root@s170 .ssh]#

注：非对称加密方式下，公钥是可以公开的，而私钥必须妥善保管！

client端：

测试一下免登录ssh。

[root@s156 .ssh]# ssh -p21702 xxx.170
Last login: Sun May 20 11:14:50 2012 from 180.168.215.167
[root@s170 ~]#
[root@s170 ~]# ls
anaconda-ks.cfg  backup  install.log  install.log.syslog  setup
[root@s170 ~]# exit
logout

Connection to s170 closed.
[root@s156 .ssh]#