How to backup directories from local to remote ?
rsync is a powerfull tool to synchronize the files and directories. Can be use for local or remote using ssh.
Source Tutorial : https://www.thegeekstuff.com/2010/09/rsync-command-examples/
rsync options source destination
Example 1. Synchronize Two Directories in a Local Server
To sync two directories in a local computer, use the following rsync -zvr command.
$ rsync -zvr /var/opt/installation/inventory/ /root/temp
In the above rsync example:
-z is to enable compression
-r indicates recursive
Example 2. Preserve timestamps during Sync using rsync -a
rsync option -a indicates archive mode. -a option does the following,
Preserves symbolic links
Preserves owner and group
Now, executing the same command provided in example 1 (But with the rsync option -a) as shown below:
$ rsync -azv /var/opt/installation/inventory/ /root/temp/
Example 3. Synchronize Only One File
To copy only one file, specify the file name to rsync command, as shown below.
$ rsync -v /var/lib/rpm/Pubkeys /root/temp/Pubkeys
Example 4. Synchronize Files From Local to Remote
rsync allows you to synchronize files/directories between the local and remote system.
$ rsync -avz /root/temp/ firstname.lastname@example.org:/home/me/temp/
While doing synchronization with the remote server, you need to specify username and ip-address of the remote server. You should also specify the destination directory on the remote server. The format is username@machinename:path
As you see above, it asks for password while doing rsync from local to remote server.
Sometimes you don’t want to enter the password while backing up files from local to remote server. For example, If you have a backup shell script, that copies files from local to remote server using rsync, you need the ability to rsync without having to enter the password.
To do that, setup ssh password less login as we explained earlier.
Example 5. Synchronize Files From Remote to Local
When you want to synchronize files from remote to local, specify remote path in source and local path in target as shown below.
$ rsync -avz email@example.com:/var/lib/rpm /root/temp
Example 6. Remote shell for Synchronization
rsync allows you to specify the remote shell which you want to use. You can use rsync ssh to enable the secured remote connection.
Use rsync -e ssh to specify which remote shell to use. In this case, rsync will use ssh.
$ rsync -avz -e ssh firstname.lastname@example.org:/var/lib/rpm /root/temp
Example 7. Do Not Overwrite the Modified Files at the Destination
In a typical sync situation, if a file is modified at the destination, we might not want to overwrite the file with the old file from the source.
Use rsync -u option to do exactly that. (i.e do not overwrite a file at the destination, if it is modified). In the following example, the file called Basenames is already modified at the destination. So, it will not be overwritten with rsync -u.
$ rsync -avzu email@example.com:/var/lib/rpm /root/temp
Example 8. Synchronize only the Directory Tree Structure (not the files)
Use rsync -d option to synchronize only directory tree from source to the destination. The below example, synchronize only directory tree in recursive manner, not the files in the directories.
$ rsync -v -d firstname.lastname@example.org:/var/lib/ .
Example 9. View the rsync Progress during Transfer
When you use rsync for backup, you might want to know the progress of the backup. i.e how many files are copies, at what rate it is copying the file, etc.
rsync –progress option displays detailed progress of rsync execution as shown below.
$ rsync -avz --progress email@example.com:/var/lib/rpm/ /root/temp/
You can also use rsnapshot utility (that uses rsync) to backup local linux server, or backup remote linux server.
Example 10. Delete the Files Created at the Target
If a file is not present at the source, but present at the target, you might want to delete the file at the target during rsync.
In that case, use –delete option as shown below. rsync delete option deletes files that are not there in source directory.
$ rsync -avz --delete firstname.lastname@example.org:/var/lib/rpm/ .
Example 11. Do not Create New File at the Target
If you like, you can update (Sync) only the existing files at the target. In case source has new files, which is not there at the target, you can avoid creating these new files at the target. If you want this feature, use –existing option with rsync command.
$ rsync -avz --existing email@example.com:/var/lib/rpm/ .
Example 12. View the Changes Between Source and Destination
This option is useful to view the difference in the files or directories between source and destination.
In the above example, between the source and destination, there are two differences. First, owner and group of the file Dirname differs. Next, size differs for the file Basenames.
Now let us see how rsync displays this difference. -i option displays the item changes.
$ rsync -avzi firstname.lastname@example.org:/var/lib/rpm/ /root/temp/
Example 13. Include and Exclude Pattern during File Transfer
rsync allows you to give the pattern you want to include and exclude files or directories while doing synchronization.
$ rsync -avz --include 'P*' --exclude '*' email@example.com:/var/lib/rpm/ /root/temp/
In the above example, it includes only the files or directories starting with ‘P’ (using rsync include) and excludes all other files. (using rsync exclude ‘*’ )
Example 14. Do Not Transfer Large Files
You can tell rsync not to transfer files that are greater than a specific size using rsync –max-size option.
$ rsync -avz --max-size='100K' firstname.lastname@example.org:/var/lib/rpm/ /root/temp/
max-size=100K makes rsync to transfer only the files that are less than or equal to 100K. You can indicate M for megabytes and G for gigabytes.
Example 15. Transfer the Whole File
One of the main feature of rsync is that it transfers only the changed block to the destination, instead of sending the whole file.
If network bandwidth is not an issue for you (but CPU is), you can transfer the whole file, using rsync -W option. This will speed-up the rsync process, as it doesn’t have to perform the checksum at the source and destination.
$ rsync -avzW email@example.com:/var/lib/rpm/ /root/temp