Production needs: companies generally have more than one web in order to ensure data consistency and files on the web server or samba on nfs, convenient unified management,
Meanwhile, in order to find a secure data server can be real-time synchronization of data can be achieved by inotify + rsync + script
I. Introduction inotify monitoring software
inotify can monitor changes to synchronize data server directory information, using asynchronous file system event monitoring mechanism, the use of event-driven
Mechanisms, without having to get through a polling mechanism, such as cron and other events, linux kernel from 2.6.13 onwards inotify support, through inotify can monitor
Control the file system to add, delete, modify, move, and other events.
ll / proc / sys / fs / inotify # files listed below, indicates that the server kernel supports inotify
-rw-r - r-- 1 root root 0 Dec 7 10:10 max_queued_events inotify event queue Maximum Length Default: 16384
-rw-r - r-- 1 root root 0 Dec 7 10:10 max_user_instances inotify instance created for each user Maximum Default: 128
-rw-r - r-- 1 root root 0 Dec 6 05:54 max_user_watches number of files that can be monitored (single-process), the default values: 8192
inotify kernel-level functions required by the user space program, installation package:
yum install inotify-tools based source epel
inotify-tools package main documents:
1, inotifywait command
Waiting for a specific file system events (open closedelete, etc.) occur on the monitored file or directory, commonly used in real-time synchronization
Directory monitor directly without using a one-time option to monitor, when the operation will end when the directory secondary monitor
inotifywait command common options
-m, --monitor always an event listener
-d, --daemon in daemon mode execution, and -m similar, with the use -o
-r, --recursive recursive directory monitor data changes
-q, --quiet output a small amount of event information
--exclude <pattern> exclude specified file or directory, the extended use of the regular expression matching mold
Type realization
--excludei <pattern> and exclude similar insensitive
-o, --outfile <file> print events to a file, right equivalent to the standard output
-s, --syslogOutput send error corresponds to the standard error output syslog
--timefmt <fmt> Specifies the time the output format
--timefmt <fmt> Time Format, a reference man 3 strftime
% Y Year information, including information Century
% Y year information does not include information Century
% M month display, range 01-12
% D day of the month, range 01-31
% H hours information, using 24-hour clock, range 00-23
% M min, range 00-59
Example:
--timefmt "%Y-%m-%d %H:%M"
--format <fmt> specified output format; i.e., the actual content monitoring output
-e specify the listener specified event, if omitted, it indicates that all events are listening
示例： -e create,delete,moved_to,close_write, attrib
Common combinations
Continuous background monitoring and logging
inotifywait -mrq /data/www -o /root/inotify.log --timefmt "%Y-%m-%d %H:%M" --format "%T %w%f event: %e"
Continuous background monitoring specific events
inotifywait -mrq /data -o /root/inotify.log --timefmt "%F %H:%M" --format "%T %w%f event: %;e" -e create,delete,moved_to,close_write,attrib
2、inotifywatch：
Collecting the monitored file system statistics, statistics refers to the number of file system events
Second, the specific implementation
192.168.12.27 inotify server
192.168.12.57 rsync server
Monitoring inotify server data automatically synchronized to change rsync server
192.168.12.57 ：
1, the installation package
yum install rsync
2, the server configuration file to modify rsync
we /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 = 192.168.12.0/24 [backup] path = /backup/ comment = backup read only = no auth users = rsyncuser secrets file = /etc/rsync.pass
3、生成服务器验证文件
echo "rsyncuser:123456" > /etc/rsync.pass
chmod 600 /etc/rsync.pass
4、创建文件用于存放备份文件
mkdir /backup
chmod 600 /backup/
5、启动rsyncd服务
rsync --daemon 可加入/etc/rc.d/rc.local实现开机启动
systemctl start rsyncd
192.168.12.27：
1、安装软件包，创建需要监控备份的文件夹
yum install inotify-tools
2、生成密码文件，如果没有会变成交互式命令，创建后rsync会使用该密码自动同步
echo "123456" > /etc/rsync.pass
chmod 600 /etc/rsync.pass
3、测试能否同步到rsync服务器
rsync -avz --password-file=/etc/rsync.pass /data/www/ [email protected]::backup
4、创建实时监控脚本
vi inotify_rsync.sh
#!/bin/bash # #******************************************************************** #Author: swh #QQ: 786529083 #Date: 2019-08-01 #FileName：inotify_rsync.sh #blog: https://blog.51cto.com/14322729 #Description：The test script #Copyright (C): 2019 All rights reserved #******************************************************************** SRC='/data/www/' DEST='[email protected]::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 done
