Archiving and Compression

It is always good to have a backup. You can use the cp command, or you can archive it using tar and compress it using gzip, that way you will save some space.

Archiving and Compression

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This will archive and compress using gzip! Be sure to end in '.gz' and use -z, -z is for gzip:

tar -zcvf [newArchiveName.tar.gz] [file/dir you want to archive]

This will archive files and compressing using bzip2! Be sure to end name with '.bz2' and use -j. -j is for bzip:

tar -jcvf [newArchive.tar.bz2] [file/dir]

I.e: backed up your home directory and stored it into Backups directory, perserves permissions, verbose, gzip/compressions, etc.:

tar -cvpzf ~/Backups/backup.tar.gz ~/  

How I backed up my /etc/letsencrypt directory, did the same to my /var/www:

DATE=$(date +"%d-%b-%Y"); tar -zcvf ./letsencrypt-$DATE.tar.gz letsencrypt/

• NOTE, when you extract the files it will create the file where you are unless you specify.

How to extract .tar.xz file

tar -xf linux-5.6.13.tar.xz
tar -xvf linux-5.6.13.tar.xz
tar -Jxvf linux-5.6.13.tar.xz
## extract tar.xz files aka .txz file ##
tar --xz -xf archive.txz

Archiving Files

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tar - an archiving utility that DOES NOT do compression. Allows us to create archive. Collects a number of files/dir into a single file for backup/archiving.

To archive files, where c -> create ; v -> Verbose ; f -> file or archive device; * -> all files and directories:

tar -cvf  [newArchive.tar] [dir/file you want to archive]

To eXtract the contents from the archived file:

tar -xvf  [Archive.tar]

To show the contents of the archive folder (-t):

tar -tvf  [Archive.tar]

To add a file/dir to an archived file:

tar -rvf  [Archive.tar] [file/dir]

To perserve the permissions of the original file:

tar -p

To compress/uncompress the file size using gzip (Recommend you SHOULD do it, why not):

tar -z

Real world example from work: eXtract, compress(gzip), verbose, file

tar -xzvf [archive.tar.gz] [dir/file]

File Compression

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gzip - compresses quicker (z)

Compress file:

gzip [file] [file]

Eextract/normalize file

gzip -d [file.gz] 

Provide a compression information (a compression/uncompression ratio):

gzip -l [file.gz] ...

To decompress:

gunzip -d [file.tar.gz]

How to view compressed file:

• You can use gunzip then cat it:

gunzip scan.runzero.gz
gunzip -d scan.runzero.gz
gzip -d scan.runzero.gz

• You can also use zcat:

zcat scan.runzero.gz

You can even redirect it to a file like: zcat scan.runzero.gz > file

• zless:

zless scan.runzero.gz

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bzip2 - bzip2, bunzip2 - a block-sorting file compressor. bzip2 compresses files using the Burrows-Wheeler block sorting text compression algorithm, and Huffman coding. Bzip2 uses LESS SPACE for the compressed file (j).

Compresses file

bzip2 [file] 

Extract files from bzip

bunzip2 [file.bz2]