Catalog

One 、rsync

1、rsync Introduce

2、 Synchronization mode

3、rsync command

4、rsync experiment

（1）rsync Local replication

 （2） experiment ： Remote Replication ( Downlink replication )

Two 、inotify

1、 brief introduction

2、inotifywait（ Command to continuously monitor and output monitoring results in real time )

3、 experiment

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One 、rsync

1、rsync Introduce

rsync It's an open source 、 fast 、 Multifunctional 、 It is an excellent tool to realize full and incremental local or remote data synchronous backup . And the attribute information of the original data can not be changed , Realize the backup and migration of data .

rsync The software is suitable for unix/linux/windows And so on

rsync It is a fast and very convenient file copying tool . It can reproduce locally , Remote Replication , Or remote daemon replication , It provides a large number of parameters to control all aspects of its behavior , It also allows very flexible ways to realize file transfer and replication

With its delta-transfer Algorithm famous .

rsync Listening port ：873

rsync Operation mode ：C/S

2、 Synchronization mode

Full volume backup ：
All the original data is transmitted
Send the original document and the new document together
Copy in full , Low efficiency

Incremental backup

Before transmitting data, compare the data you have with the data I have through some algorithms , Transmit different data through the network （ Incremental replication , Efficient ）

3、rsync command

Constant option	explain
-r	Recursive mode , Contains all the files in the directory and subdirectories
-l	For symbolic link files, still copy as symbolic link files
-v	Show details of the synchronization process
-z	Compress when transferring files goD
-p	Keep the permission tag of the file
-a	Archiving mode , Recurse and keep object properties , Equate to -rlpt
-t	Keep the time stamp of the file
-g	Keep the group tag of the file （ For super users only ）
-o	Keep the owner tag of the file （ For super users only ）
-H	Keep hard link files
-A	Retain ACL Attribute information
-D	Keep equipment files and other special files
--delete	Delete files that exist in the target location but not in the original location
--checksum	Decide whether to skip files based on the checksums of objects

4、rsync experiment

（1）rsync Local replication

Rsync  192.168.182.135

Client  192.168.182.160

 

 

 （2） experiment ： Remote Replication ( Downlink replication )

Rsync  192.168.182.135

Client  192.168.182.160

Basic environment configuration

systemctl stop firewalld.service

setenforce 0

# To configure rsync The source server

rpm -q rsync

yum -y install rsync

# establish /etc/rsyncd.conf The configuration file 
vim /etc/rsyncd.conf # Add the following configuration 

uid = nobody #root
gid = nobody #root
use chroot = yes # Locked in the source directory  
address = 192.168.184.50 # Monitor address 
port 873 # Listening port  tcp/udp 873, It can be done by  cat /etc/services | grep rsync  see  
log file = /var/log/rsyncd.log # Log file location  
pid file = /var/run/rsyncd.pid # Store process ID File location of  
hosts allow = 192.168.184.0/24 # The client address allowed to access 
[wwwroot] 
path = /var/www/html # The actual path to the source directory  
comment = Document Root of www.ljm.com 
read only = yes # Is it read-only  
dont comperss = *.gz *.bz2 *.tgz *.zip *.rar *.z # File types that are no longer compressed during synchronization  
auth users = backuper # Authorized account , Multiple accounts are separated by spaces  
secrets file = /etc/rsyncd_users.db # Data file for storing account information  
--------------------------------------------
uid = nobody
gid = nobody
use chroot = yes 
address = 192.168.184.50
port 873 
log file = /var/log/rsyncd.log 
pid file = /var/run/rsyncd.pid 
hosts allow = 192.168.184.0/24
[wwwroot] 
path = /var/www/html 
comment = Document Root of www.ljm.com 
read only = yes 
dont comperss = *.gz *.bz2 *.tgz *.zip *.rar *.z 
auth users = backuper 
secrets file = /etc/user.db
# Such as anonymity , Just put one of them  “auth users”  and  “secrets file The configuration item can be removed 

# Create data file for backup account

vim /etc/user.db

backuper:123456 # There is no need to establish a system user with the same name

chmod 600 /etc/user.db

# Ensure that all users have access to the source directory /var/www/html Have read permission

mkdir -p /var/www/html

chmod +r /var/www/html/

ls -ld /var/www/html/

# start-up rsync Service program

rsync --daemon

netstat -natp | grep rsync

close rsync service

kill $(cat /var/run/rsyncd.pid)

rm -rf /var/run/rsyncd.pid

  Client synchronization

  Secret free interaction

 --delete

Two 、inotify

1、 brief introduction

You can monitor changes in the file system , And make notification response adjustment

inotify Kernel parameters ( Optimize )

/etc/sysctl.conf( Kernel parameter configuration file )

inotifywait:                                  For continuous monitoring , Real time output results
inotifywatch:                                For short-term monitoring , Output the results after the task is completed
max_queue_events                   3 Monitor event queue size
max_user_instances                  The maximum number of monitoring instances
max user watches                       The maximum number of monitoring files per instance

2、inotifywait（ Command to continuously monitor and output monitoring results in real time )

Format : inotifywait[ Parameters ]

Common parameters	explain
-m	Continuous monitoring
-r	Recursively monitor all child objects
-q	Simplify the output
-e	Specify which event types to monitor

3、 experiment

Server side ： modify rsync The configuration file

vim /etc/rsyncd.conf

uid = root

gid = root

read only = no # Turn off read-only , Uplink synchronization requires writable permissions

kill `cat /var/run/rsyncd.pid`

netstat -natp | grep rsync

rsync --daemon

netstat -natp | grep rsync

client ：inotify Kernel parameters

cat /proc/sys/fs/inotify/max_queued_events

cat /proc/sys/fs/inotify/max_user_instances

cat /proc/sys/fs/inotify/max_user_watches

vim /etc/sysctl.conf

fs.inotify.max_queued_events = 32768 # Monitor the time queue , The default is 16384

fs.inotify.max_user_instances = 1024 # The maximum number of monitoring instances , The default is 128

fs.inotify.max_user_watches = 1048576 # The maximum number of monitoring files per instance , The default is 8192

# When you want to monitor the directory 、 When the amount of file data is large or changes frequently , It is recommended to increase the parameter value

sysctl -p

# Client installation inotify-tools

yum -y install gcc gcc-c++

tar zxvf inotify-tools-3.14.tar.gz -C /opt

cd /opt/inotify-tools-3.14/

./configure

make && make install

# perform “inotifywait” command , Then on the server side, go to /var/www/html Add files to directory 、 Moving files , Tracking screen output

inotifywait -mrq -e modify,create,move,delete /abc

# The server writes the trigger synchronization script

vim /opt/inotify.sh

#!/bin/bash

INOTIFY_CMD="inotifywait -mrq -e create,delete,move,modify,attrib /abc/"

RSYNC_CMD="rsync -apzH --delete --password-file=/etc/server.pass /abc/ [email protected]::wwwroot/"

$INOTIFY_CMD | while read DIRECTORY EVENT FILE

do

if [ $(pgrep rsync | wc -l) -le 0 ] ; then

$RSYNC_CMD

fi

Done

chmod +x /opt/inotify.sh

chmod +x /etc/rc.d/rc.local

echo "/opt/inotify.sh" >> /etc/rc.d/rc.local

verification ：

192.168.182.160 client stay /var/www/html Add operation Open the copied 160 The client performs operation command monitoring

Client script It will be executed If inotify Trigger rsync process   The script will be triggered to automatically synchronize

here 192.168.182.135 Server side Same directory Automatic backup