What is tar? The term tar means tape archive. In good old day’s system admin used to take backups on tape drives. But now we use tar utility to take backup to other digital media. Majority of Linux system administrators use tar utility in linux to compress archive file which is usually called tarball , simply tar , bzip and gzip. This utility is tremendously used to create compressed archive files which We have already discussed file compression and archive in our tutorial. So you can also refer to this tutorials
COMPRESSION AND ARCHIVING PART1 and COMPRESS AND ARCHIVE PART 2
In this article we will going to see practical usage of tar command examples including how to create archive files using (tar, tar.gz and tar.bz2) compression, how to extract archive file, how to extract a single file, how to view content of file, how to verify a file, how to add files or directories to archive file, and how to estimate the size of tar archive file, etc.
1. To create an tar archive of a file using tar command
You can create an uncompressed tar archive using option cvf
This is the very basic command to create a tar archive.
Syntax : tar cvf archivefile.tar /path/to/file
c – this switch creates a new archive
v – this switch is for verbose meaning it displays list files which are processed.
f – this switch is for file name
[root@shahid ~]# ls -ltrh total 16K -rw-------. 1 root root 1.6K Feb 3 17:42 anaconda-ks.cfg -rw-r--r--. 1 root root 1.7K Feb 3 17:44 initial-setup-ks.cfg -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt
In above output we can see that in current directory we have file health.txt. we will archive this file now
[root@shahid ~]# tar -cvf health.tar health.txt health.txt [root@shahid ~]# ll total 28 -rw-------. 1 root root 1597 Feb 3 17:42 anaconda-ks.cfg drwxr-xr-x. 2 root root 42 Jun 21 09:35 DirA -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 10240 Jun 21 09:34 health.tar -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 1645 Feb 3 17:44 initial-setup-ks.cfg
In above example we have archived file health .txt and now you can see health.tar archived file in current directory.
2. Creating compressed tar archive of file
To create zipped archive or compressed archive of file we will use option z which is gzip compression
Syntax : tar cvzf archivename.tar.gz filename.txt
[root@shahid ~]# tar cvzf health.tar.gz health.txt health.txt [root@shahid ~]# ls -ltrh total 32K -rw-------. 1 root root 1.6K Feb 3 17:42 anaconda-ks.cfg -rw-r--r--. 1 root root 1.7K Feb 3 17:44 initial-setup-ks.cfg -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 10K Jun 21 09:34 health.tar drwxr-xr-x. 2 root root 42 Jun 21 09:35 DirA -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz [root@shahid ~]#
In above example you can see file zise difference of health.tar (uncompressed archive) and health.tar.gz (compressed archive)
3. Create tar.bz2 Archive File
Now we will create tar archive file with bzip compression which takes more time to compress and decompress but is highly compressed archive in other words it takes less space that gzip compression
we wil use option j instead of z
syntax : tar cvfj archive.tar.bz filename
[root@shahid ~]# tar cvfj health.tar.bz health.txt health.txt [root@shahid ~]# ls -ltrh total 36K -rw-------. 1 root root 1.6K Feb 3 17:42 anaconda-ks.cfg -rw-r--r--. 1 root root 1.7K Feb 3 17:44 initial-setup-ks.cfg -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 10K Jun 21 09:34 health.tar drwxr-xr-x. 2 root root 42 Jun 21 09:35 DirA -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz -rw-r--r--. 1 root root 141 Aug 1 09:01 health.tar.bz
in above example you can see diff between gz and bz compressed archives. 4.
4. Create tar archive of diretory
creating archive of directory is same as file. Syntax: tar cvfj archivedirectory.tar.bz /path/to/directory
[root@shahid ~]# ls -ltrh total 40K -rw-------. 1 root root 1.6K Feb 3 17:42 anaconda-ks.cfg -rw-r--r--. 1 root root 1.7K Feb 3 17:44 initial-setup-ks.cfg -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 10K Jun 21 09:34 health.tar -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz -rw-r--r--. 1 root root 141 Aug 1 09:01 health.tar.bz drwxr-xr-x. 3 root root 53 Aug 1 09:14 DirA -rw-r--r--. 1 root root 177 Aug 1 09:16 DirB.tar.bz [root@shahid ~]# tar tvf Dir DirA/ DirB.tar.bz
5. To list content of archive using tar command <v/h4>
You can View the file content of tar archive without extracting using option tvf
You can view the *.tar file content before extracting as shown below.
[root@shahid ~]# tar tvf health.tar -rw-r--r-- root/root 24 2016-04-10 21:50 health.txt [root@shahid ~]#
To view content of tar.gz archive you can use option tvfz
[root@shahid ~]# tar tvfz health.tar.gz -rw-r--r-- root/root 24 2016-04-10 21:50 health.txt [root@shahid ~]#
to view contents of tar.bz file you can use option tvfj
[root@shahid ~]# tar tvfj health.tar.bz -rw-r--r-- root/root 24 2016-04-10 21:50 health.txt
6. To untar archived tar file
You can extract a tar file by using following command with an option x (which is for extract). Below example shows how command is used to untar file
health.tar. This will untar in current working directory
[root@shahid ~]# ll total 36 -rw-------. 1 root root 1597 Feb 3 2016 anaconda-ks.cfg drwxr-xr-x. 3 root root 53 Aug 1 09:14 DirA -rw-r--r--. 1 root root 177 Aug 1 09:16 DirB.tar.bz -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 10240 Jun 21 09:34 health.tar -rw-r--r--. 1 root root 141 Aug 1 09:01 health.tar.bz -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz -rw-r--r--. 1 root root 1645 Feb 3 17:44 initial-setup-ks.cfg [root@shahid ~]# tar xvf health.tar health.txt [root@shahid ~]# ll total 40 -rw-------. 1 root root 1597 Feb 3 2016 anaconda-ks.cfg drwxr-xr-x. 3 root root 53 Aug 1 09:14 DirA -rw-r--r--. 1 root root 177 Aug 1 09:16 DirB.tar.bz -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 10240 Jun 21 09:34 health.tar -rw-r--r--. 1 root root 141 Aug 1 09:01 health.tar.bz -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 1645 Feb 3 2016 initial-setup-ks.cfg [root@shahid ~]#
if you want to extract in different directory then you can use option -C followed by path to directory with command tar xvf
[root@shahid ~]# ll total 40 -rw-------. 1 root root 1597 Feb 3 2016 anaconda-ks.cfg drwxr-xr-x. 3 root root 53 Aug 1 09:14 DirA -rw-r--r--. 1 root root 177 Aug 1 09:16 DirB.tar.bz -rwxr-xr-x. 1 root root 61 Mar 2 11:19 epoch_converter.pl -rw-r--r--. 1 root root 10240 Jun 21 09:34 health.tar -rw-r--r--. 1 root root 141 Aug 1 09:01 health.tar.bz -rw-r--r--. 1 root root 144 Jul 31 12:09 health.tar.gz -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt -rw-r--r--. 1 root root 1645 Feb 3 2016 initial-setup-ks.cfg [root@shahid ~]# ll DirA total 0 drwxr-xr-x. 2 root root 42 Aug 1 09:15 DirB -rw-r--r--. 1 root root 0 Aug 1 09:14 file1 -rw-r--r--. 1 root root 0 Aug 1 09:14 file2 -rw-r--r--. 1 root root 0 Aug 1 09:14 file3 [root@shahid ~]# tar xvf health.tar -C DirA/ health.txt [root@shahid ~]# ll DirA total 4 drwxr-xr-x. 2 root root 42 Aug 1 09:15 DirB -rw-r--r--. 1 root root 0 Aug 1 09:14 file1 -rw-r--r--. 1 root root 0 Aug 1 09:14 file2 -rw-r--r--. 1 root root 0 Aug 1 09:14 file3 -rw-r--r--. 1 root root 24 Apr 10 21:50 health.txt [root@shahid ~]#7. To compress archive and delete original files using tar command
To make compressed tar of contents of files and remove original contents in current directory you can use below command. This command helps in situation where you don't have enough space. This process archive contents while already archived contents are being deleted simultaneously tar cvfj archive.tar.bz * --remove-files[root@shahid DirB]# ls -ltrh total 0 -rw-r--r--. 1 root root 0 Aug 8 12:07 fileA -rw-r--r--. 1 root root 0 Aug 8 12:07 fileB -rw-r--r--. 1 root root 0 Aug 8 12:07 fileC [root@shahid DirB]# tar cvfj files.tar.bz * --remove-files fileA fileB fileC [root@shahid DirB]# ls -ltrh total 4.0K -rw-r--r--. 1 root root 143 Aug 8 12:07 files.tar.bz [root@shahid DirB]#More commands coming soon .....
