Archive

Archive for April, 2009

Resetting file permission with rpm

April 26th, 2009 No comments

Did you know that you can reset file permission to what they were when you installed the package. This may become helpful if somebody made a mistake and change the permission on a number of files (This never happen right?). This is where the command ;
“rpm –setperms <package>” become handy.

In our example we will change the permission on the “find” command.

# Let's find out what package contains the "/usr/bin/find" command
# rpm -qf /usr/bin/find
findutils-4.2.27-5.el5

# Let's see what are the actual permission of the find program (755).
# ls -l /usr/bin/find
-rwxr-xr-x 1 root root 151244 Jul  7  2008 /usr/bin/find

# Let's change them to 777 with the chmod command
# chmod 777 /usr/bin/find

# Now the program "find" have this permission.
# ls -l /usr/bin/find
-rwxrwxrwx 1 root root 151244 Jul  7  2008 /usr/bin/find

# Let's run our command to reset all files included in the package "findutils".
# rpm --setperms findutils

# You can see now that the permission of the 'find' are back to their initial state.
# ls -l /usr/bin/find
-rwxr-xr-x 1 root root 151244 Jul  7  2008 /usr/bin/find

Be aware that this command only reset the permission and not the owner/group of the file, as you can see from the example below.

# ls -l /usr/bin/find
-rwxr-xr-x 1 root root 151244 Jul  7  2008 /usr/bin/find
# chmod 777 /usr/bin/find
# chown jacques.jacques /usr/bin/find
# ls -l /usr/bin/find
-rwxrwxrwx 1 jacques jacques 151244 Jul  7  2008 /usr/bin/find
# rpm --setperms findutils
# ls -l /usr/bin/find
-rwxr-xr-x 1 jacques jacques 151244 Jul  7  2008 /usr/bin/find
Categories: Admin

Adding and removing IP aliases

April 20th, 2009 No comments

You need to add an IP address on interface eth0 ? Use the following command to activate it.

ifconfig eth0:1 192.168.1.177 netmask 255.255.255.0

Now you want to delete it ? No problem, use the following command ;

ifconfig eth0:1 del 192.168.1.177

You can also create a file /etc/sysconfig/network-scripts/ifcfg-eth0:1 to have the IP automatically come up upon reboot.

# cat /etc/sysconfig/network-scripts/ifcfg-eth0:1
TYPE=Ethernet
# Device Name
DEVICE=eth0:1
# Boot Protocol none,bootp,dhcp
BOOTPROTO=none
# IP Address
IPADDR=192.168.1.177
# Netmask
NETMASK=255.255.255.0
# Normal user cannot activate/deactivate it
USERCTL=no
# IPv6 Actvated
IPV6INIT=no
# Use the parent interface
ONPARENT=yes
# yes = Modify /etc/resolv.conf if DNS directive is set
#       If using DCHP, then yes is the default
# no  = Do not modify /etc/resolv.conf
PEERDNS=no
Categories: Network

Doing more with less

April 18th, 2009 No comments

We usually use the “less” command to browse the content of a text file. We use the [Page-Up], [Page-Down], [Down-Arrow], [Up-Arrow] keys to move within the file, but did you know that you can do more with the less command ?

You can see the content of a rpm file

# less flash-plugin-9.0.124.0-release.i386.rpm
 Name        : flash-plugin                 Relocations: (not relocatable)
 Version     : 9.0.124.0                    Vendor: Adobe Systems Inc.
 Release     : release                      Build Date: Tue 25 Mar 2008 12:21:32 PM EDT
 Install Date: (not installed)              Build Host: fplayerbuild2-lnx.macromedia.com
 Group       : Applications/Internet        Source RPM: flash-plugin-9.0.124.0-release.src.rpm
 Size        : 8161247                      License: Commercial
 Signature   : (none)
 Packager    : Adobe Systems Inc.
 URL         : http://www.adobe.com/downloads/
 Summary     : Adobe Flash Player 7.0
drwxr-xr-x     2 root    root        0 Mar 25  2008 /usr/lib/flash-plugin
 -rw-r--r--    1 root    root    34516 Mar 24  2008 /usr/lib/flash-plugin/LICENSE
 -rw-r--r--    1 root    root     3180 Mar 24  2008 /usr/lib/flash-plugin/README
 -rwxr--r--    1 root    root     1367 Mar 24  2008 /usr/lib/flash-plugin/homecleanup
 -rwxr-xr-x    1 root    root   115888 Mar 25  2008 /usr/lib/flash-plugin/libflashplayer.so
 -rwxr--r--    1 root    root     3116 Mar 24  2008 /usr/lib/flash-plugin/setup
 drwxr-xr-x    2 root    root        0 Mar 25  2008 /usr/share/doc/flash-plugin-9.0.124.0
 -rw-r--r--    1 root    root     3180 Mar 25  2008 /usr/share/doc/flash-plugin-9.0.124.0/readme.txt
 (END)

View the content of zip file :

$ less StudioPress.zip
Archive:  StudioPress.zip   196759 bytes   42 files
drwxr-xr-x  2.3 unx        0 bx stor 17-Sep-08 09:05 StudioPress/
-rw-r--r--  2.3 unx     3848 tx defN 14-Jan-08 09:05 StudioPress/comments.php
-rw-r--r--  2.3 unx      231 tx defN 14-Jan-08 09:05 StudioPress/searchform.php
-rw-r--r--  2.3 unx      169 tx defN  4-Feb-08 09:44 StudioPress/adsense_top.php
-rw-r--r--  2.3 unx     1393 tx defN  5-Feb-08 06:50 StudioPress/home.php
-rw-r--r--  2.3 unx     1411 tx defN 14-Jan-08 09:05 StudioPress/functions.php

View the content of tar or tgz file

$ less update_inv.tar
drwxr-xr-x jacques/jacques   0 2008-01-03 20:48:50 update_inv/
drwxr-xr-x jacques/jacques   0 2008-03-22 13:52:07 update_inv/log/
-rw-rw-r-- jacques/jacques   0 2008-03-22 13:52:07 update_inv/log/update_inv.log
drwxr-xr-x jacques/jacques   0 2008-03-22 13:52:33 update_inv/html/
-rw-rw-r-- jacques/jacques 941 2008-03-26 19:24:51 update_inv/html/gumby.html
drwxr-xr-x jacques/jacques   0 2008-03-22 13:52:07 update_inv/tmp/
-rwxrwxr-x jacques/jacques  19059 2008-03-26 19:00:43 update_inv/update_inventory.py
update_inv.tar (END)
Categories: Scripting