(LinuxWorld) -- As a Linux consultant and programmer, I find many newcomers
to Linux have preconceived ideas of how Linux should work, which leads to
confusion and problems.
Whether they are former Macintosh or Windows users, Linux newbies are
accustomed to frequent crashes and rebooting. PC users often sport a
worldview where the expression of a computer's power is limited to the
software loaded on a local hard disk. Some believe all computers should work
the way their last computer worked.
Of course, the more technically inclined understand this is simply not the
case. Tasks don't, and probably won't, always work on Linux the same way they
do in Windows.
Linux newbies may be... confused by not needing to reboot their machines
daily,awed by the ability to format a floppy and access other programs at the
same time,surprised to find they are denied access to their L... (more)
(LinuxWorld) -- My last SysAdmin column was a modest attempt to bring some
basic awareness on Linux 2.4 firewalling. This week we will continue on the
security-focused path, bringing forth a plethora of knowledge for the
uninitiated. The topic: PortSentry from Psionic Software.
PortSentry is an easy-to-install application that is designed to assist a
Linux user in their attempts to stop those cold-hearted crackers from
breaching the mighty fortress that is your Linux machine. Specifically,
PortSentry runs as a daemon on the protected host. When running, it listens
to TCP/UDP por... (more)
(LinuxWorld) -- In our most recent SysAdmin article I promised an overview of
Snort, the open source network intrusion detection system. I considered not
writing the article after seeing the volume of options available to users of
Snort, but decided that since I have received International Fame and
Recognition from my security series, that I would go ahead with the article.
The following article does not cover Snort in great detail. Snort is a large
program in terms of its available options, and would take several articles to
cover comprehensively. Instead, here is a brief overvi... (more)
(LinuxWorld) -- As I write this column, the world suffers infestation by yet
another Internet worm, and again the worms are intended to attack
Microsoft-based machines. Fortunately for my company, we don't run any
Microsoft-based machines, but the Nimda worm still affects us.
Nimda eats our bandwidth since other companies sharing our subnet are running
infectious Windows 98, NT, and 2000 machines. These diseased, ill-maintained
beasts from the land of insufficient light are now trying to infest our
stable, secure, long running, easy-to-use, well-behaved Linux machines. (Can
... (more)
Q: I use sendmail and a POP mail server on a Linux box. I am desperately
looking for a way to filter incoming messages processed by sendmail based on
their subject names and enclosure names. I would like to do this to filter
spam and potentially dangerous viruses.
A: I'm not sure if you are talking about the MTA (Mail Transfer Agent, aka
sendmail) or the MUA (Mail User Agent, aka Netscape Mail). However, there are
solutions for both. Most graphical clients have built-in filtering that you
can use.
On the server side, you can use a program called procmail. Procmail is
installed b... (more)
Joshua Drake is the co-founder of Command Prompt, Inc., a PostgreSQL and Linux custom development company. He is also the current author of the Linux Networking HOWTO, Linux PPP HOWTO, and Linux Consultants HOWTO. His most demanding project at this time is a new PostgreSQL book for O'Reilly, 'Practical PostgreSQL'
Scott Sellers
Anthony Franco
Daniel Morris
Wayne Walls
Niki Acosta
Jereme Hancock
Oren Michels
Marvin Wheeler
Douglas Kim
Ken Guiberson
