Lesson 1.6: Archive, compress, unpack, and uncompress files using tar, gzip, and bzip2

Non Compressed Archive ( Plain Archive ) / TAR

tar [option] <files/dir to be archived>
- [option]
- -c : create archive
- -v : show details (verbose)
- -f : archive filename
- -t : list contents of an archive
- -r : add new files/dirs into an archive
- -x : extract files/dirs from an archive
- -z : create a gzip compressed archive (.tar.gz or .tgz)
- -j : create a bzip2 compressed archive (.tar.bz2 or .tbz)

Creating compressed archives with tar

Suppose you want to bundle all the files inside the etc directory with conf extension ( ls /etc/*.conf ).In such cases you can do this by: tar -cvf <tar_filename> <source> <destination>

[sanjeeb@server ~]$ tar -cvf conffile.tar /etc/*.conf /home/sanjeeb/
 
[sanjeeb@server ~]$ ls
conffile.tar  Documents  image.png  Music     Public   Templates  Videos
Desktop       Downloads  Marketing  Pictures  Scripts  test

Listing the content of the Tar file

tar -tvf <tar_filename>

[sanjeeb@server ~]$  tar -tvf conffile.tar 
-rw-r--r-- sanjeeb/sanjeeb     1525 2024-03-15 18:56 home/sanjeeb/image.png
-rw------- sanjeeb/sanjeeb       20 2024-04-06 15:35 home/sanjeeb/.lesshst
-rw------- sanjeeb/sanjeeb    10752 2024-04-06 15:32 home/sanjeeb/.viminfo
...

Appending new file to the existing Tar file

tar -tvf <tar_filename> <source>

[sanjeeb@server ~]$ tar -rvf conffile.tar image.png

Compressed Archive

A compressed archive is a single file or data structure that contains one or more files or directories that have been reduced in size using compression algorithms. The compression process removes redundant or unnecessary information from the files, reducing their size and conserving storage space. Compressed archives are commonly used for storing and transferring large amounts of data efficiently.

gzip

Compressing a tar file using gzip

[sanjeeb@server ~]$ gzip conffile.tar 
[sanjeeb@server ~]$ ls
conffile.tar.gz  Documents  --help     Marketing  Pictures  Scripts    test
Desktop          Downloads  image.png  Music      Public    Templates  Videos

De-Compressing a tar file using gunzip

[sanjeeb@server ~]$ gunzip conffile.tar.gz 
[sanjeeb@server ~]$ ls
conffile.tar  Documents  --help     Marketing  Pictures  Scripts    test
Desktop       Downloads  image.png  Music      Public    Templates  Videos

To create archive as well as compress archive in one command using gzip

tar -zcvf <tar.gz filename> <source> <destination>

 [sanjeeb@server ~]$ tar -zcvf confile.tar.gz /etc/*.conf /home/sanjeeb/

bzip2

To create archive as well as compress archive in one command using bzip2

[sanjeeb@server ~]$ tar -zcvf confile.tar.tbz /etc/*.conf /home/sanjeeb/
 
[sanjeeb@server ~]$ ls -lh 
total 558M
-rw-r--r--. 1 sanjeeb sanjeeb  76M Apr  6 18:07 confile.tar.gz
-rw-r--r--. 1 sanjeeb sanjeeb 227M Apr  6 18:11 confile.tar.tbz

Compressing Tools

GZIP

Compression Command: gzip
Decompression Counterpart: gunzip
Standard .gz

[sanjeeb@assignmentserver class]$ ls -lh 
-rw-r--r--. 1 sanjeeb sanjeeb  817 Sep 19 17:00 xattr.conf
 
[sanjeeb@assignmentserver class]$ gzip xattr.conf 
 
[sanjeeb@assignmentserver class]$ ls -lh 
-rw-r--r--. 1 sanjeeb sanjeeb  423 Sep 19 17:00 xattr.conf.gz
 
[sanjeeb@assignmentserver class]$ gunzip xattr.conf.gz

BZIP2

Compression Command: bzip
Decompression Counterpart: bunzip
Standard .bz2

[sanjeeb@assignmentserver class]$ bzip2 xattr.conf 
 
[sanjeeb@assignmentserver class]$ ls -lh | grep .bz2 
-rw-r--r--. 1 sanjeeb sanjeeb  490 Sep 19 17:00 xattr.conf.bz2
 
[sanjeeb@assignmentserver class]$ bunzip2 xattr.conf.bz2 
 
[sanjeeb@assignmentserver class]$ ls -lh
-rw-r--r--. 1 sanjeeb sanjeeb  817 Sep 19 17:00 xattr.conf
 
# To provide full information using -v
[sanjeeb@assignmentserver class]$ bzip2 -v xattr.conf
  xattr.conf:  1.667:1,  4.798 bits/byte, 40.02% saved, 817 in, 490 out.

ZIP

Compression Command: zip
Decompression Counterpart: unzip
Standard .zip ( Windows Compatible )

Generating Compressed Counterpart of the zip file without compressing the file itself.

# Using Bzip
[sanjeeb@assignmentserver class]$ gzip -v -c vconsole.conf > vconsole.conf.gz
vconsole.conf:	 -7.1% -- replaced with stdout
 
[sanjeeb@assignmentserver class]$ ls -lh
-rw-r--r--. 1 sanjeeb sanjeeb   28 Sep 19 17:00 vconsole.conf       # Original File
-rw-r--r--. 1 sanjeeb sanjeeb   62 Sep 19 18:26 vconsole.conf.gz    # Compressed Counterpart
 
# Using Zip
[sanjeeb@assignmentserver class]$ zip -o dracut.conf.zip dracut.conf 
  adding: dracut.conf (deflated 12%)
 
[sanjeeb@assignmentserver class]$ ls | grep dracut 
dracut.conf
dracut.conf.zip