Roderick Smith Archive

Roderick W. Smith is the author or co-author of over a dozen books, including Advanced Linux Networking and Linux Power Tools. He can be reached at rodsmith@rodsbooks.com.
Mastering udev
Learn how to use dynamic device files in Linux
Spring Cleaning, Geek Style
How to clean the clutter that consumes your computer.
Creating PDFs
Sharing documents such as papers, reports, and specifications is made easy with Adobe’s Portable Document Format (PDF). Here’s a primer on how to create PDFs on Linux.
Partimage Backups
Whatever you’re doing, stop! Have you backed up your systems today? If so, great! If not, try Partimage to make copies of entire partitions.
Tracking Down Unnecessary Servers
To keep your system running securely and efficiently, you should periodically audit your system, looking for servers that need not be running. Here’s how to do it.
Tweaking Fonts with FontForge
Access Control Lists
If you've used Linux for a long time, you're probably quite familiar with file permissions. Indeed, managing permissions is a critical part of managing a Linux system.
Using APT on RPM-Based Systems
Managing packages can be a tricky undertaking, even with package tools like the RPM Package Manager (RPM), the package management tool used by Conectiva, Fedora, Mandrake, Red Hat, SuSE, Yellow Dog, and many other distributions. With RPM, you may try to install a package, only to find that it depends on others you don't have. Or, you might discover that your packages are several versions out of date and then have to track down and install potentially dozens of updates to fix security and other problems with the old packages.
Creating Custom RPMs, Part Two
Last month's column looked at the basics of generating RPMs, including the format of the all-important .spec file. In theory, those principles should be enough to let you create .spec files and RPMs for a number of purposes. In practice, however, RPM generation is complex enough that some examples are sure to help. So, this month's column presents two examples: creating a non-program RPM and creating a program RPM.
Creating Custom RPMs, Part One
RPMs can be a great way to manage the packages you install on your system. Unfortunately, not everything you might want to install is available in RPM form. Perhaps you need a more recent version of a program than the one that ships with your distribution; or maybe it's a program you wrote yourself; or perhaps it's just something that's very obscure. Similar dilemmas can occur with non-program packages, such as font or clip art collections.
Linux and the AMD64
Linux was created on the first 32-bit CPU in the x86 CPU family, the 80386. But the days of 32-bit computing are coming to an end. Luckily, the AMD64 provides compatibility features that ease the transition. Here's a hands-on guide to building and benchmarking a 64-bit Linux desktop based on AMD64.
SSH Tunneling
Security has long been an important computer issue, but it's become increasingly relevant as the number and severity of threats has risen.
Customizing your Video Mode
Suffering eyestrain from looking at a flickering monitor? Can't quite fit everything you want in your display? Ordinarily, problems like these call for a new monitor, or at least switching to a different standard resolution -- say, going down in resolution if the problem is flicker, or going up from 1024x768 to 1280x1024 to get more screen real estate.
A First Look at the New CIFS Driver
Samba is a file and print server that runs under Linux and other Unix-like operating systems. Samba is an implementation of the Server Message Block (SMB) protocol, also known as the Common Internet File System (CIFS), which is a popular file- and printer-sharing protocol on Windows.
SANE Network Scanning
Document and image scanners have become an integral part of many offices. With a scanner, you can quickly digitize photos, diagrams, and even textual documents for electronic alteration and distribution.
Printing with CUPS
Printing via Linux has always been a bit tricky, but the situation is improving in many ways. At the forefront of this change is the shift from the old Line Printer Daemon (LPD) printing system, as implemented in the BSD LPD or LPRng servers, to the newer Common Unix Printing System (CUPS). CUPS is now the default printing system of most Linux distributions, as well as with some non-Linux systems, such as Mac OS X.
Managing Xft Fonts
Linux's font handling is undergoing a major change. In the past, Linux relied on X's native font-handling systems (known as X core fonts), but over time, these systems have become rather ragged. The solution is an entirely different font system, known as Xft.
Managing SMB/CIFS Networks with net
Samba 3.0 has been released -- it's the latest version of a server that's becomes an essential part of Linux. Samba is primarily a server for the Server Message Block (SMB) protocol (also known as the Common Internet File System, or CIFS), the protocol used by Windows computers for file and printer sharing. Using Samba, Linux systems seamlessly integrate into existing Windows networks. Without Samba, Linux couldn't serve as a "drop-in" replacement for Windows file and print servers.
Multibooting with GRUB, Part 2
Last month's column introduced the powerful Grand Unified Boot Loader (GRUB), a utility that enables you to boot one of many operating systems when you start your computer. That column looked at basic GRUB configuration, including setting up GRUB on a floppy disk to boot Linux.
Multibooting with GRUB, Part 1
Many Linux computers are multi-boot systems, or computers that can boot from a variety of operating systems, including multiple instances of Linux.
Working Inside the Bochs
Sometimes a single operating system just isn't enough. However impractical, many users keep multiple computers on their desk, sometimes dedicating each computer to a very specific, solitary task. But wasting hardware isn't always necessary. Computers are very flexible machines -- flexible enough that one computer can emulate another. Emulation allows a physical computer to pretend to be another one.
Trapping Crackers with Honeypots
World War II saw some impressive acts of deception, some to hide secrets, and some to mislead the other side. The Germans developed the Enigma machine, an early electronic encryption device. The Allies broke the Enigma code, and so learned a great deal about German military actions. And in an effort to mask the D-Day invasion, the Allies launched a project known as "Fortitude." Under Fortitude, the Allies created fake armies, composed largely of inflatable rubber tanks and other "vehicles," carefully placed to convince the Germans that the main Allied invasion would take place at Pas-de-Calais rather than Normandy. Fortitude was a great success: it lured German forces away from the Normandy beaches, helping the Allies establish a presence on the European mainland.
AMANDA Network Backups
One problem faced by administrators of large and small networks alike is performing backups. While backups are simple to perform and a variety of software and hardware is available to help, the logistics of reliably archiving even a handful of machines are quite onerous. Having each user backup his or her own computer seems an obvious solution, but is really quite impractical: equipping each workstation and server with its own backup hardware is prohibitively expensive, and asking users to schedule and run their own backups is tantamount to ignoring the problem altogether.
Partition Resizing with GNU Parted
You've installed Linux on a computer and everything's coming up roses -- X is working, your servers are running, and so on. Suddenly, you run into a problem! When writing a new file, you receive an ominous error message: "No space left on device." Your disk -- or at least one of your partitions -- is full.
Spam, Spam, Spam, Spam, Spam
As users and system administrators, we fight spam (unsolicited bulk e-mail) every day. For instance, it's not uncommon these days to receive more spam than legitimate email. What's worse, the amount of spam traversing the Internet has grown substantially every year for the past several years. Indeed, spam is becoming a threat to the Internet. The mail servers of ISPs are becoming overburdened, forcing ISPs to buy more hardware and pay for more bandwidth just to handle spam. Spam has become such a serious problem that a conference on the subject was held recently in Cambridge, Massachusetts.
Network Monitoring with Snort
One of the keys to any type of security is knowledge. To keep a network secure, you must know about security in general, but you must also be aware of the environment in which your computers operate.
Simplifying Remote VNC Logins
Virtual Network Computing (VNC) is an increasingly popular remote-access protocol. VNC is available for Linux, Windows, Mac OS, and others. (If you're unfamiliar with VNC or don't have VNC installed on your Linux system, see this month's "Tech Support" column on page 62 for instructions on how to install and use VNC.)
Using Samba Pseudo-Printers
The Linux Samba server supports the Server Message Block (SMB) protocol (also known as the Common Internet File System, or CIFS, protocol). Microsoft Windows uses SMB natively to share files and printers. Thus, Samba is most commonly used to turn a Linux box into a file and print server for Windows clients. Indeed, Samba is so effective that Samba enables Linux to sneak into otherwise Windows-domainated shops, with management none the wiser. However, Samba can be employed as much more than a file and print server. Samba supports many configuration options and it can perform a variety of complex tasks.