gzip does not seem to be working

Submitted by edwardsmarkf on Mon, 07/02/2012 - 10:27 Pro Licensee

Linux server.edwardsmarkf.com 2.6.18-274.3.1.el5.028stab094.3ent #1 SMP Thu Sep 22 14:53:28 MSD 2011 i686 i686 i386 GNU/Linux

please see forum:

https://www.virtualmin.com/node/22650

attached is the setting and here is the result:

[root@server ~]# cd /usr/local/backup [root@server backup]# ls -ltr total 9737476 blah blah blah -rw-r--r-- 1 root root 9961394303 Jul 2 00:37 home-backup.tar [root@server backup]#

Status: 
Closed (works as designed)

Comments

Submitted by andreychek on Mon, 07/02/2012 - 10:30

Jamie, the issue he's seeing is as follows:

i notice the Filesystem-backup option "Compress archive?" does not seem to do anything.

i have selected "gzip" as an option.

note that merely naming the tar file tar.gz does not work either, but i thought i would give it a shot anyways.

Submitted by JamieCameron on Mon, 07/02/2012 - 14:44

You need to both select "Compress archive", and name the destination file something.tar.gz .

You can check the actual format of the file with a command like :

file /usr/local/backup/home-backup.tar.gz

Submitted by edwardsmarkf on Tue, 07/03/2012 - 12:15 Pro Licensee

renaming the output file was the first thing i tried - please see attached

here is my result of my latest backup attempt:

-rw-r--r-- 1 root root 9952993483 Jul 3 00:35 home-backup.tar -rw-r--r-- 1 root root 9953055171 Jul 3 10:06 home-backup.tar.gz

and note that the gz file is not compressed, since i can run "tar -t"

tar -t -f home-backup.tar.gz | head -3 home/ home/greatamericanaccents/ home/greatamericanaccents/fcgi-bin/

Submitted by JamieCameron on Tue, 07/03/2012 - 12:25

Using tar isn't a good test, as at least on my system it will still list a gzip-compressed file automagically.

You should use the file command to see the real format.

Submitted by edwardsmarkf on Tue, 07/03/2012 - 12:54 Pro Licensee

ok i am running it again, but notice the size difference between the two backups, no real difference!

-rw-r--r-- 1 root root 9952993483 Jul 3 00:35 home-backup.tar

-rw-r--r-- 1 root root 9953055171 Jul 3 10:06 home-backup.tar.gz

the regular backup ran after midnight, and the other one ran at 10:06 this morning.

if worse comes to worse, i could make something in crontab that gzips it....

please don't get me wrong, i am totally sold in virtualmin/webmin! this is really pretty minor.

Submitted by JamieCameron on Tue, 07/03/2012 - 13:02

I'd be interested to see what the file command says about those files..

Submitted by edwardsmarkf on Tue, 07/03/2012 - 13:12 Pro Licensee

its taking awhile to run.... and i am curious too.

but what happens if it was in reality compressed all along and you were right all along? i am not sure if my ego could take that.

Submitted by edwardsmarkf on Tue, 07/03/2012 - 13:52 Pro Licensee

hmm well "file" is not natively installed on centOS, but running this:

gzip -d home-backup.tar.gz ;

OK that seems to work!

-rw-r--r-- 1 root root 9952993483 Jul 3 00:35 home-backup-Tuesday.tar

-rw-r--r-- 1 root root 12447846400 Jul 3 11:27 home-backup.tar

its moments like this that make me realize i need to use a fake-name in public forums.

=== update:

yum -y install file ;

[root@server backup]# file home-backup-Tuesday.tar home-backup-Tuesday.tar: gzip compressed data, from Unix, last modified: Tue Jul 3 00:00:06 2012

Submitted by JamieCameron on Tue, 07/03/2012 - 13:46

Ok, glad the mystery was explained :-)