How to divide a large 'tar' archive file into multiple files of a specific size

Are you worried about transferring or uploading large files over the network ？ Don't worry now , Because you can specify large and small pieces by dividing your file , Move your files in bits to handle slow Internet speeds .

Here we should briefly use the archive files to create bin and divide them into a selected large piece . We use tar, stay Linux One of the most popular archiving tools on split Tools help us split archive files into small pieces .

Before we go any further , We pay attention to how to use these tools ,tar and split The general syntax of the command is as follows ：

# tar options archive-name files 
# split options file "prefix”

Let's study some examples to demonstrate the main concepts .

Example 1： We can create an archive file as follows ：

[[email protected] ~]# tar -cvjf test.tar.br2 test/*
test/fold/
test/guid.txt
test/perm.txt
test/rock.html
test/Rock.txt
test/Rocky/
test/Rocky/1.txt
test/Rocky/2.txt
test/Rocky/3.txt
test/Rocky/4.txt
test/Rocky/5.txt
test/rocky.c
test/rocky.sh
test/suid.txt
test/test.tar.gz
[[email protected] ~]# ls
test  test.tar.br2

Make sure that the archive file has been created and check its size , We can use ls command ：

[[email protected] ~]# ls -lh test.tar.br2
-rw-r--r-- 1 root root 2.9M Jul  3 22:21 test.tar.br2

Then use split Tools , We press the following test.tar.br2 Archive files are divided into each size 1M Small pieces ：

[[email protected] ~]# split -b 1M test.tar.br2 "test.tar.br2.part"
[[email protected] ~]# ls -lh
total 5.8M
drwxr-xr-x 4 root root  177 Jul  3 09:04 test
-rw-r--r-- 1 root root 2.9M Jul  3 22:21 test.tar.br2
-rw-r--r-- 1 root root 1.0M Jul  3 22:26 test.tar.br2.partaa
-rw-r--r-- 1 root root 1.0M Jul  3 22:26 test.tar.br2.partab
-rw-r--r-- 1 root root 917K Jul  3 22:26 test.tar.br2.partac

As you can see from the above command output ,tar The archive has been divided into 3 Parts of .

Be careful ： In the above split In command , Options -b Used to specify the size of each block , and "test.tar.br2.part" Is the prefix of each block file name created after segmentation .

Example 2： In this case , We use pipe connection as follows tar Of output to split：

[[email protected] ~]# tar -cvzf - test/* | split -b 500K - "test_2.tar.gz.part"
test/fold/
test/guid.txt
test/perm.txt
test/rock.html
test/Rock.txt
test/Rocky/
test/Rocky/1.txt
test/Rocky/2.txt
test/Rocky/3.txt
test/Rocky/4.txt
test/Rocky/5.txt
test/rocky.c
test/rocky.sh
test/suid.txt
test/test.tar.gz

Confirm these documents ：

[[email protected] ~]# ls -lh test_2.tar.gz.part*
-rw-r--r-- 1 root root 500K Jul  3 23:41 test_2.tar.gz.partaa
-rw-r--r-- 1 root root 500K Jul  3 23:41 test_2.tar.gz.partab
-rw-r--r-- 1 root root 500K Jul  3 23:41 test_2.tar.gz.partac
-rw-r--r-- 1 root root 500K Jul  3 23:41 test_2.tar.gz.partad
-rw-r--r-- 1 root root 500K Jul  3 23:41 test_2.tar.gz.partae
-rw-r--r-- 1 root root 449K Jul  3 23:41 test_2.tar.gz.partaf

In this example , If you notice, we don't need to specify an archive name , Just use '-' Symbol .

How to combine after segmentation tar file

stay Linux Successfully split in tar File or any large file , You can use cat Command combines these files . Use cat It is the most efficient and reliable way to perform combined operations .

To combine back all blocks or tar file , We issue the following order ：

[[email protected] back]# ls
test_2.tar.gz.partaa  test_2.tar.gz.partac  test_2.tar.gz.partae
test_2.tar.gz.partab  test_2.tar.gz.partad  test_2.tar.gz.partaf
[[email protected] back]# cat test_2.tar.gz.part* > backup.tar.gz
[[email protected] back]# ls
backup.tar.gz         test_2.tar.gz.partab  test_2.tar.gz.partad  test_2.tar.gz.partaf
test_2.tar.gz.partaa  test_2.tar.gz.partac  test_2.tar.gz.partae

We can see it running cat After the command , It combines all the small pieces we created previously into the same size of the original tar Archive file .

Extract the combined file , Check the contents ：

[[email protected] back]# tar -xvzf backup.tar.gz
test/fold/
test/guid.txt
test/perm.txt
test/rock.html
test/Rock.txt
test/Rocky/
test/Rocky/1.txt
test/Rocky/2.txt
test/Rocky/3.txt
test/Rocky/4.txt
test/Rocky/5.txt
test/rocky.c
test/rocky.sh
test/suid.txt
test/test.tar.gz