Squid Proxy Server Mac Address based filtering

Posted on in Categories , , , , last updated November 1, 2007

Q. I’m using squid proxy server under CentOS Linux version 5. How to filter a particular MAC address under squid?

A. Not all operating system supports Mac address based filtering. For some operating systems. Squid calls these “ARP ACLs” and they are supported on Linux, Solaris, and BSD variants.

How do I set up ACL’s based on MAC address?

Open squid.conf:
# vi /etc/squid/squid.conf
Local acl, section and append ACL as follows:
acl macf1 arp mac-address
acl macf2 arp 00:11:22:33:44:55
http_access allow macf1
http_access allow macf2
http_access deny all

Save and close the file. Restart squid server:
# /etc/init.d/squid restart

Redhat Enterprise Linux (RHEL) install ImageMagick RPM for manipulating images

Posted on in Categories , , last updated July 6, 2007

Q. How do I install ImageMagick software under Redhat enterprise Linux version 4 update 5?

A. ImageMagick is an image display and manipulation tool for the X Window System. ImageMagick can read and write JPEG, TIFF, PNM, GIF, and Photo CD image formats. It can resize, rotate, sharpen, color reduce, or add special effects to an image, and when finished you can either save the completed work in the original format or a different
one. ImageMagick also includes command line programs for creating animated or transparent .gifs, creating composite images, creating thumbnail images, and more.

ImageMagick is one of your choices if you need a program to manipulate and display images. If you want to develop your own applications which use ImageMagick code or APIs, you need to install ImageMagick-devel as well.

INSTALL ImageMagick

Use up2date command to install ImageMagick, enter ( <= RHEL 4 only): # up2date install ImageMagick
OR use yum if you are using Fedora Core/CentOS/RHEL 5:
# yum install ImageMagick

Essential ImageMagick Hacks/Tips/Faqs…

Now use ImageMagick from command line or GUI: