Monday, May 27, 2013

How to backup / rsync file between server / location





How to Backup Linux? 15 rsync Command Examples

rsync stands for remote sync.
rsync is used to perform the backup operation in UNIX / Linux.
rsync utility is used to synchronize the files and directories from one location to another in an effective way. Backup location could be on local server or on remote server.

Important features of rsync

  • Speed: First time, rsync replicates the whole content between the source and destination directories. Next time, rsync transfers only the changed blocks or bytes to the destination location, which makes the transfer really fast.
  • Security: rsync allows encryption of data using ssh protocol during transfer.
  • Less Bandwidth: rsync uses compression and decompression of data block by block at the sending and receiving end respectively. So the bandwidth used by rsync will be always less compared to other file transfer protocols.
  • Privileges: No special privileges are required to install and execute rsync

Syntax

$ rsync options source destination
Source and destination could be either local or remote. In case of remote, specify the login name, remote server name and location.

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
building file list ... done
sva.xml
svB.xml
.
sent 26385 bytes  received 1098 bytes  54966.00 bytes/sec
total size is 44867  speedup is 1.63
$
In the above rsync example:
  • -z is to enable compression
  • -v verbose
  • -r indicates recursive
Now let us see the timestamp on one of the files that was copied from source to destination. As you see below, rsync didn’t preserve timestamps during sync.

$ ls -l /var/opt/installation/inventory/sva.xml /root/temp/sva.xml
-r--r--r-- 1 bin  bin  949 Jun 18  2009 /var/opt/installation/inventory/sva.xml
-r--r--r-- 1 root bin  949 Sep  2  2009 /root/temp/sva.xml

Example 2. Preserve timestamps during Sync using rsync -a

rsync option -a indicates archive mode. -a option does the following,
  • Recursive mode
  • Preserves symbolic links
  • Preserves permissions
  • Preserves timestamp
  • 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/
building file list ... done
./
sva.xml
svB.xml
.
sent 26499 bytes  received 1104 bytes  55206.00 bytes/sec
total size is 44867  speedup is 1.63
$
As you see below, rsync preserved timestamps during sync.
$ ls -l /var/opt/installation/inventory/sva.xml /root/temp/sva.xml
-r--r--r-- 1 root  bin  949 Jun 18  2009 /var/opt/installation/inventory/sva.xml
-r--r--r-- 1 root  bin  949 Jun 18  2009 /root/temp/sva.xml

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

sent 42 bytes  received 12380 bytes  3549.14 bytes/sec
total size is 12288  speedup is 0.99

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/ thegeekstuff@192.168.200.10:/home/thegeekstuff/temp/
Password:
building file list ... done
./
rpm/
rpm/Basenames
rpm/Conflictname

sent 15810261 bytes  received 412 bytes  2432411.23 bytes/sec
total size is 45305958  speedup is 2.87
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 thegeekstuff@192.168.200.10:/var/lib/rpm /root/temp
Password:
receiving file list ... done
rpm/
rpm/Basenames
.
sent 406 bytes  received 15810230 bytes  2432405.54 bytes/sec
total size is 45305958  speedup is 2.87

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 thegeekstuff@192.168.200.10:/var/lib/rpm /root/temp
Password:
receiving file list ... done
rpm/
rpm/Basenames

sent 406 bytes  received 15810230 bytes  2432405.54 bytes/sec
total size is 45305958  speedup is 2.87

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.
$ ls -l /root/temp/Basenames
total 39088
-rwxr-xr-x 1 root root        4096 Sep  2 11:35 Basenames

$ rsync -avzu thegeekstuff@192.168.200.10:/var/lib/rpm /root/temp
Password:
receiving file list ... done
rpm/

sent 122 bytes  received 505 bytes  114.00 bytes/sec
total size is 45305958  speedup is 72258.31

$ ls -lrt
total 39088
-rwxr-xr-x 1 root root        4096 Sep  2 11:35 Basenames

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 thegeekstuff@192.168.200.10:/var/lib/ .
Password:
receiving file list ... done
logrotate.status
CAM/
YaST2/
acpi/

sent 240 bytes  received 1830 bytes  318.46 bytes/sec
total size is 956  speedup is 0.46

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 thegeekstuff@192.168.200.10:/var/lib/rpm/ /root/temp/
Password:
receiving file list ...
19 files to consider
./
Basenames
     5357568 100%   14.98MB/s    0:00:00 (xfer#1, to-check=17/19)
Conflictname
       12288 100%   35.09kB/s    0:00:00 (xfer#2, to-check=16/19)
.
.
.
sent 406 bytes  received 15810211 bytes  2108082.27 bytes/sec
total size is 45305958  speedup is 2.87
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.
# Source and target are in sync. Now creating new file at the target.
$ > new-file.txt

$ rsync -avz --delete thegeekstuff@192.168.200.10:/var/lib/rpm/ .
Password:
receiving file list ... done
deleting new-file.txt
./

sent 26 bytes  received 390 bytes  48.94 bytes/sec
total size is 45305958  speedup is 108908.55
Target has the new file called new-file.txt, when synchronize with the source with –delete option, it removed the file new-file.txt

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.
First, add a new-file.txt at the source.
[/var/lib/rpm ]$ > new-file.txt
Next, execute the rsync from the target.
$ rsync -avz --existing root@192.168.1.2:/var/lib/rpm/ .
root@192.168.1.2's password:
receiving file list ... done
./

sent 26 bytes  received 419 bytes  46.84 bytes/sec
total size is 88551424  speedup is 198991.96
If you see the above output, it didn’t receive the new file new-file.txt

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.
At the source:
$ ls -l /var/lib/rpm
-rw-r--r-- 1 root root  5357568 2010-06-24 08:57 Basenames
-rw-r--r-- 1 root root    12288 2008-05-28 22:03 Conflictname
-rw-r--r-- 1 root root  1179648 2010-06-24 08:57 Dirnames
At the destination:
$ ls -l /root/temp
-rw-r--r-- 1 root root    12288 May 28  2008 Conflictname
-rw-r--r-- 1 bin  bin   1179648 Jun 24 05:27 Dirnames
-rw-r--r-- 1 root root        0 Sep  3 06:39 Basenames
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 thegeekstuff@192.168.200.10:/var/lib/rpm/ /root/temp/
Password:
receiving file list ... done
>f.st.... Basenames
.f....og. Dirnames

sent 48 bytes  received 2182544 bytes  291012.27 bytes/sec
total size is 45305958  speedup is 20.76
In the output it displays some 9 letters in front of the file name or directory name indicating the changes.
In our example, the letters in front of the Basenames (and Dirnames) says the following:
> specifies that a file is being transferred to the local host.
f represents that it is a file.
s represents size changes are there.
t represents timestamp changes are there.
o owner changed
g group changed.

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 '*' thegeekstuff@192.168.200.10:/var/lib/rpm/ /root/temp/
Password:
receiving file list ... done
./
Packages
Providename
Provideversion
Pubkeys

sent 129 bytes  received 10286798 bytes  2285983.78 bytes/sec
total size is 32768000  speedup is 3.19
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' thegeekstuff@192.168.200.10:/var/lib/rpm/ /root/temp/
Password:
receiving file list ... done
./
Conflictname
Group
Installtid
Name
Sha1header
Sigmd5
Triggername

sent 252 bytes  received 123081 bytes  18974.31 bytes/sec
total size is 45305958  speedup is 367.35
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  thegeekstuff@192.168.200.10:/var/lib/rpm/ /root/temp
Password:
receiving file list ... done
./
Basenames
Conflictname
Dirnames
Filemd5s
Group
Installtid
Name

sent 406 bytes  received 15810211 bytes  2874657.64 bytes/sec
total size is 45305958  speedup is 2.87

6 rsync Examples to Exclude Multiple Files and Directories using exclude-from

Rsync is very powerful tool to take backups, or sync files and directories between two different locations (or servers).
You know this already, as we presented you with practical examples on rsync earlier.
In a typical backup situation, you might want to exclude one or more files (or directories) from the backup. You might also want to exclude a specific file type from rsync.
This article explains how to ignore multiple files and/or directories during rsync with examples.
First, create a sample directory structure as shown below (with some empty files) that can be used for testing purpose.
$ cd ~
$ mkdir -p source/dir1/dir2
$ mkdir -p source/dir3
$ touch source/file1.txt
$ touch source/file2.txt
$ touch source/dir1/dir2/file3.txt
$ touch source/dir3/file4.txt
The above command will create a source directory (under your home directory) with the following structure.
source
- file1.txt
- file2.txt
- dir1
  - dir2
    - file3.txt
- dir3
  - file4.txt

1. Exclude a specific directory

If you don’t want to sync the dir1 (including all it’s subdirectories) from the source to the destination folder, use the rsync –exclude option as shown below.

$ rm -rf destination

$ rsync -avz --exclude 'dir1' source/ destination/
building file list ... done
created directory dest
./
file1.txt
file2.txt
dir3/
dir3/file4.txt
Verify to make sure dir1 is not copied from source directory to destination directory.
$ find destination
destination
destination/file2.txt
destination/file1.txt
destination/dir3
destination/dir3/file4.txt

2. Exclude multiple directories that matches a pattern

The following example will exclude any directory (or subdirectories) under source/ that matches the pattern “dir*”
$ rm -rf destination

$ rsync -avz --exclude 'dir*' source/ destination/
building file list ... done
created directory destination
./
file1.txt
file2.txt
Verify the destination directory to make sure it didn’t copy any directories that has the keyword “dir” in it.
$ find destination
destination
destination/file2.txt
destination/file1.txt

3. Exclude a specific file

To exclude a specific file, use the relative path of the file in the exclude option as shown below.
$ rm -rf destination

$ rsync -avz --exclude 'dir1/dir2/file3.txt' source/ destination/
building file list ... done
created directory destination
./
file1.txt
file2.txt
dir1/
dir1/dir2/
dir3/
dir3/file4.txt
Verify the destination directory to make sure it didn’t copy the specific file ( dir1/dir2/file3.txt in this example).
$ find destination
destination
destination/file2.txt
destination/file1.txt
destination/dir1
destination/dir1/dir2
destination/dir3
destination/dir3/file4.txt

4. Exclude path is always relative

If you are not careful, you might make this mistake.
In the following example, the exclude option seems to have a full path (i.e /dir1/dir2/file3.txt). But, from rsync point of view, exclude path is always relative, and it will be treated as dir1/dir2/file3.txt. In the example below, rsync will look for dir1 under source directory (and not under / root directory).
$ rsync -avz --exclude '/dir1/dir2/file3.txt' source/ destination/
So, the above command is exactly same as the following. Just to avoid confusion (and to make it easy to read), don’t give / in front of the exclude path.
$ rsync -avz --exclude 'dir1/dir2/file3.txt' source/ destination/

5. Exclude a specific file type

To exclude a specific file type that has a specific extension, use the appropriate pattern. For example, to exclude all the files that contains .txt as extension, do the following.
$ rsync -avz --exclude '*.txt' source/ destination/
building file list ... done
created directory destination
./
dir1/
dir1/dir2/
dir3/
Verify the destination directory to make sure it didn’t copy the *.txt files.
$ find destination
destination
destination/dir1
destination/dir1/dir2
destination/dir3
Note: The above is very helpful, when you want to backup your home directory, but exclude all those huge image and video files that has a specific file extension.

6. Exclude multiple files and directories at the same time

When you want to exclude multiple files and directories, you can always specify multiple rsync exclude options in the command line as shown below.
$ rsync -avz --exclude file1.txt --exclude dir3/file4.txt source/ destination/
Wait. What if I had tons of files that I want to exclude from rsync?
I can’t keep adding them in the command line using multiple –exclude, which is hard to read, and hard to re-use the rsync command for later.
So, the better way is to use rsync –exclude-from option as shown below, where you can list all the files (and directories) you want to exclude in a file.
First, create a text file with a list of all the files and directories you don’t want to backup. This is the list of files and directories you want to exclude from the rsync.
$ vim exclude-list.txt
file1.txt
dir3/file4.txt
Next, execute the rsync using –exclude-from option with the exclude-list.txt as shown below.
$ rm -rf destination

$ rsync -avz --exclude-from 'exclude-list.txt' source/ destination/
building file list ... done
created directory destination
./
file2.txt
dir1/
dir1/dir2/
dir1/dir2/file3.txt
dir3/
Verify the desitination directory to make sure the files and directories listed in the exclude-list.txt file is not backed-up.
$ find destination
destination
destination/file2.txt
destination/dir1
destination/dir1/dir2
destination/dir1/dir2/file3.txt
destination/dir3

No comments: