Rsync + inotify Real-time Data Synchronization

Remote Sync, remote Synchronization

1. Rsync command usage
Format: rsync [option ..] target directory of the source directory
Difference: synchronization and Replication
Copy: completely copy the source to the target
Synchronization: Incremental copy, only transmitted changed data

2. Local Synchronization
Rsync [option ..] local directory 1 local directory 2 # Synchronize Directory 1 to directory 2
Rsync [option...] local directory 1/local directory 2 # synchronize data under directory 1 to directory 2
-A: Archive mode, equivalent to-rlptgod
-V: displays details.
-Z: Enable compression/Decompression during transmission
-N: test the synchronization process without actual modification # used with-avz
-- Delete: Delete unnecessary documents in the target folder # used with-avz

3. Remote Synchronization
Rsync + SSH
-- Command
Rsync [email protected]: remote directory/# list SSH server resources
Rsync [option ..] [email protected]: remote directory local directory # downstream (download) not commonly used
Rsync [option...] local directory [email protected]: remote directory # commonly used for uploading
-A: Archive mode, equivalent to-rlptgod
-V: displays details.
-Z: Enable compression/Decompression during transmission
-N: test the synchronization process without actual modification # used with-avz
-- Delete: Delete unnecessary documents in the target folder # used with-avz
Tip: Add/after the directory to synchronize the data in the directory. If/is not added to the synchronization directory, the directory is synchronized.

4. Real-Time Synchronization
1) Deploy the public key and private key for SSH password-less Authentication
[[Email protected]/] # ssh-keygen # vm a generates a public key and a private key
[[Email protected]/] # ls/root/. Ssh # location where the public key and private key are generated
Id_rsa id_rsa.pub known_hosts
[[Email protected]/] # ssh-copy-ID [email protected] # pass the public key to the target host (in virtual machine B)
[[Email protected] ~] # Ls/root/. Ssh # view the Public Key uploaded to VM B
Authorized_keys # Public Key File Uploaded to the client

2) Real-time inotify Synchronization
-- Install inotify-tools in source code to monitor directory content changes
[[Email protected]/] # mkdir/myrpm
[[Email protected]/] # tar-XF/tools/inotify-tools-3.13.tar.gz-C/myrpm # Decompression
[[Email protected]/] # Yum-y install GCC make # Install the compiling environment GCC make
[[Email protected]/] # cd/myrpm/inotify-tools-3.13/
[[Email protected] inotify-tools-3.13] #./configure # generate MAKEFILE file
[[Email protected] inotify-tools-3.13] # Make # compile to binary
[[Email protected] inotify-tools-3.13] # make install # Install
[[Email protected] inotify-tools-3.13] # Which inotifywait # view command location
/Usr/local/bin/inotifywait

-- Inotifywait basic usage
Inotifywait [Option] destination folder
-M: continuous monitoring (do not exit after an event is captured)
-R: recursive monitoring, including subdirectories and files
-Q: Reduce screen output information
-QQ: no screen output information
-E: Specifies the monitored event categories such as modify move create Delete attrib.

3) Write shell scripts
-- Use the while loop to perform repeated checks for a single monitoring
Syntax:
While [condition]
Do
Loop execution
Done

-- Implementation
# Vim/jluocc/rsync. Sh
#/Bin/bash
While inotifywait-rqq/OPT
Do
Rsync-Az -- delete/opt/[email protected]:/OPT # synchronize data in the local opt directory to the/OPT directory of another host
Done
# Chmod + x/jluocc/rysnc. Sh # grant the script execution permission
#/Jluocc/rsync. Sh # Run the script to synchronize Real-time Data

4) Implement the data synchronization script at startup
# Vim/etc/rc. Local # Open the default file for system startup
/Jluocc/rsync. Sh # Write the absolute path of the script you just wrote in the file
# Chmod + x/etc/rc. Local # RC. Local does not have the execution permission by default. You must grant the execution permission.

5. Summary
Rsync: Data Synchronization
Inotifywait: monitors data changes under a specified directory, and returns corresponding results when changes occur.
Shell script: Implements real-time inotifywait monitoring. Once data changes, rsync data is synchronized to achieve real-time data synchronization.

Rsync + inotify Real-time Data Synchronization