inotify和rsync实现实时同步
首先先用两台主机实现rsyncc同步
服务端：
[root@centos7 data 14:20:35]#echo "rsyncuser:123" > /etc/rsync.pass 生成验证文件
[root@centos7 data 14:21:13]#chmod 600 /etc/rsync.pass
[root@centos7 data 14:21:19]#mkdir /backup 准备目录
[root@centos7 data 15:18:52]#vim /etc/rsyncd.conf 配置/etc/rsyncd.conf
uid = root
gid = root
use chroot = no
max connections = 0
ignore errors
exclude = lost+found/
log file = /var/log/rsyncd.log
pid file = /var/run/rsyncd.pid
lock file = /var/run/rsyncd.lock
reverse lookup = no
hosts allow = 192.168.0.0/24
[backup]
path = /backup/
comment = backup
read only = no
auth users = rsyncuser
secrets file = /etc/rsync.pass
comment = ftp export area
[root@centos7 ~ 14:45:22]#systemctl start rsyncd 开启服务，监听873端口

客户端：
[root@centos6 ~ 12:02:50]#echo "123" > /etc/rsync.pass 生成密码文件
[root@centos6 ~ 15:45:39]#chmod 600 /etc/rsync.pass
[root@centos6 ~ 15:45:47]#rsync -avz --password-file=/etc/rsync.pass /data/ rsyncuser@192.168.0.17::backup 同步数据
sending incremental file list
./
ERROR: daemon refused to receive directory "lost+found"
*** Skipping any contents from this failed directory ***
data/

sent 72 bytes received 16 bytes 176.00 bytes/sec
total size is 0 speedup is 0.00
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1039) [sender=3.0.6]

结合inotify+rsync实现同步：
[root@centos6 ~ 16:08:40]#yum -y install epel-release
[root@centos6 ~ 16:08:57]#yum -y install inotify-tools
[root@centos6 ~ 16:11:33]#vim inotify_rsync.sh

#!/bin/bash
SRC='/data/'
DEST='rsyncuser@192.168.0.17::backup'
inotifywait -mrq --timefmt '%Y-%m-%d %H:%M' --format '%T %w %f' -e create,delete,moved_to,close_write,attrib ${SRC} |while read DATE TIME DIR FILE;do
FILEPATH=${DIR}${FILE}
rsync -az --delete --password-file=/etc/rsync.pass $SRC $DEST && echo "At ${TIME} on ${DATE}, file $FILEPATH was backuped up via rsync" >> /var/log/changelist.log
#注意：因为ext系统文件系统有lost+found文件夹，所有rsync会同步成功，但命令的执行结果是失败的，所有不会写日志至/var/log/changelist.log中，要想成功，在ext系统文件系统中把&&换成||即可
done

[root@centos6 ~ 16:13:53]#./inotify_rsync.sh

在客户端创建文件

服务端几乎瞬间就能够同步