= AIX Tar =

**Summary**: ALthough AIX is by now on version 7.3 I find these old pages so fascinating I decided to keep them. On this page I'll show you how to configure tar for AIX (tar is a software utility for collecting many files into one archive file, often referred to as a tarball, for distribution or backup purposes). This page is for AIX 5.3 and AIX 6.1.\\
**Date**: Between 2010-2013 \\
**Refactor**: 21 December 2024: Checked formatting. \\
{{tag>aix}}

= TAR File Size Limitation =

The tar utility which get installed by default on AIX does not have the possibility to tar/untar files larger than 1 GB. To overcome this install the tar utility that is available on the AIX Toolbox for Linux Applications CD-ROM. I've used tar version 1.14-2 with success.

= Simple TAR usage =

== Create TAR ==

<code>
tar -cvf /scratch/myfile_20030617.tar /scratch/mydir/results/stat/*
</code>

== Extract Files From TAR ==

<code>
tar -xf myfile_20030617.tar
</code>

== Popular options ==

* -c = create
* -f = read to/from the named file (instead of the device /tape)
* -t = list contents of .tar file
* -r = append to a .tar file
* -v = verbose (tells you everything its doing)
* -x = extract contents of .tar file
* -z = compress files (not so useful for minc files)

= Use Tar to copy files between servers =

To copy a large amount of files to another server you can use tar:
# Make sure root is allowed to logon to the new server through ssh
# Tar the data and pipe it through ssh to the new server
# Check the data sizes and number of files and directories

== Root login ==

Edit the /etc/ssh/sshd_config file on the new server:
<code>
PermitRootLogin yes
#AllowGroups ssh-access
</code>
and restart the ssh service:
<code>
sudo /etc/rc.d/rc2.d/Ssshd stop
sudo /etc/rc.d/rc2.d/Ssshd start
</code>

== Tar ==

<code>
bash-3.2# tar clf - /opt/IBM/WebSphere | ssh 10.10.10.100 "tar xf - -C /opt/IBM/WebSphere"

root@10.10.10.100's password:
tar: file -C: not present in archive
bash-3.2#
</code>

Tar options explanation:
<code>
-l
            Writes an error message to standard output for each file with a link count greater than 1 whose
            corresponding links were not also archived. For example, if file1 and file2 are hard-linked together and
            only file1 is placed on the archive, then the -l flag will issue an error message. Error messages are not
            displayed if the -l flag is not specified.


-C Directory
            Causes the tar command to perform a chdir subroutine to the directory specified by the Directory variable.
            Using the -C flag allows multiple directories not related by a close common parent to be archived, using
            short relative path names. For example, to archive files from the /usr/include and /etc directories, you
            might use the following command: tar c -C /usr/include File1 File2 -C /etc File3 File4
</code>

== Check ==

Old server:
<code>
bash-3.2# du -sm /opt/IBM/WebSphere/
1490.79 /opt/IBM/WebSphere/
bash-3.2# find /opt/IBM/WebSphere/ -type f |wc -l
   16247
bash-3.2# find /opt/IBM/WebSphere/ -type d |wc -l
    2805
</code>

New server:
<code>
/opt/IBM>sudo du -sm /opt/IBM/WebSphere/
1490.66 /opt/IBM/WebSphere/
/opt/IBM>sudo find /opt/IBM/WebSphere/ -type f |wc -l
   16247
/opt/IBM>sudo find /opt/IBM/WebSphere/ -type d |wc -l
    2805
</code>

As you can see there is a small difference between the data size. This is not really a problem because the old server is in use, and there could be differences in block size etc. The amount of files is exactly the same so that is more important.