10.28 rsync工具介绍
rsync是一个实用的同步工具
需求：A目录的数据实时更新，将A的数据拷贝到B目录，每隔一小时拷贝一次
使用cp命令：
1 在A目录中找出最近1小时新增的内容拷贝到B（比较麻烦）
2 直接拷贝A目录的所有内容将B目录覆盖（浪费时间和磁盘IO）
cp命令不适用
rsync可以实现增量更新（rsync只会同步新增和有内容变更的文件）；
支持远程同步（将数据同步到不同ip的另一台机器上）；
安装rsync
[root@hyc-01-01 ~]# yum install -y rsync
将passwd同步到tmp目录下并改名为1.txt
[root@hyc-01-01 ~]# rsync -av /etc/passwd /tmp/1.txt
sending incremental file list
passwd
sent 938 bytes received 35 bytes 1,946.00 bytes/sec
total size is 846 speedup is 0.87
-a 包含多个选项
-v 可视化，可以看到拷贝的过程
将文件同步到远程机器的特定目录
[root@hyc-01-01 ~]# rsync -av /etc/passwd root@192.168.31.128:/tmp/1234.txt
The authenticity of host '192.168.31.128 (192.168.31.128)' can't be established.
ECDSA key fingerprint is SHA256:0SErfGbbc3AfFcxC92Tav9X/T/bOn8wfnvum/wnw5Xs.
ECDSA key fingerprint is MD5:b7:d4:e4:4a:4a:33:29:99:1a:2e:45:94:d9:40:17:fb.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.31.128' (ECDSA) to the list of known hosts.
[email protected]'s password:
sending incremental file list
passwd
sent 938 bytes received 35 bytes 67.10 bytes/sec
total size is 846 speedup is 0.87
其中root@可以省略，此时使用执行当前命令的用户作为登录用户
将远程机器的某文件拷贝到当前机器某个目录下
[root@hyc-01-01 ~]# rsync -av [email protected]:/etc/passwd /tmp/passwddd
[email protected]'s password:
receiving incremental file list
passwd
sent 43 bytes received 938 bytes 130.80 bytes/sec
total size is 846 speedup is 0.86
[root@hyc-01-01 ~]# ls /tmp/passwddd
/tmp/passwddd