Seven Kernels on Five Systems
I know I'm not exactly your average Linux user. I guess I have to ask, who is? But, I hope most users don't have some of the problems I see regularly. At home, I usually have five systems connected, and my business has a fair number of servers and access points on the Internet. What I've been finding, and with greater frequency, is that between software not being available on some distros and software that only builds on some kernels, I have four different distros running seven different kernels just on the five systems I have at home. As of this writing (latest kernel version 2.4.17-pre6), the latest (CVS) Internet PhoneJACK software wouldn't build on any of the four most recent kernels I installed; other software required kernels 2.4.4-2.4.8 to build. Non-overlap of kernel versions needed to build and run some software is why I have seven kernels on five systems. FreeS/WAN compiles on some, but not all kernels. Then some distros have their own problems. Mandrake 8.1, which has a lot of bells and whistles, didn't include wireless utilities or support for CardBus or my ORiNOCO card—easily remedied, but not necessarily so for newbies. Caldera has a nasty habit of providing upgrades, such as those to the kernel, but not upgrading the kernel version itself. They patch it up with security patches, then leave the source as 2.4.2. Needless to say, some software refuses to build when 2.4.4 or better is required. Most readers already will be aware of the numerous problems with Red Hat. Solution? I'm afraid I don't have one. But I do know that what I consider only niggling annoyances can become show-stoppers for newbies. And, no amount of support will push Linux into the Microsoft strongholds if these problems aren't resolved.
Vipul's Razor razor.sourceforge.net
Last month I railed against spammers. This month I have a cure. If you're running an MTA (I run several), you can stop spam via a simple global /etc/procmailrc recipe (or you can do the same just for your mail with your own personal ~/.procmailrc). Mine shunts all spam received to a spam box. I've checked the messages sent to this spam folder for over a month, and not one legitimate mail has been misdirected. Now I'm averaging one spam every three days, which I report to the razor servers, and with spams reportedly up 650% over last Christmas season, I'm happy. Requires: Perl, Perl modules Net::Ping, Net::DNS, Time::HiRes, Digest::SHA1, Mail::Internet and a strong desire to be spam-free.
Running a wireless card? Want to know how good or bad your signal strength is without running iwspy every few seconds? Well, XNetworkStrength will do it for you if you're on an X screen. You can keep an eye on your connection while you're working. Requires: libX11, glibc.
Need a simple, safe way for users to change their password? These CGI tools are compiled C programs that provide security, but you'll want them accessible only via https (not much sense changing a password over an insecure link). They also allow for users to forward mail and return a mail message (à la vacation). Unfortunately, this program won't take mailing lists into account (as vacation will). Requires: libdb1, libpam (optional), libdl, glibc, web server with PHP.
NorthStar will help you keep track of your IP allocations, equipment and locations of same. In fact, one of the nicest things about this is the way you can view your networks, devices and locations. If you have more than a few IPs or systems or locations, you'll want to look this program over. Requires: web server, Perl, PostgreSQL.
Simplyfied CD Backup scdbackup.webframe.org/main_eng.html
This backup to CD utility is actually a number of small programs to permit specific actions. There's scdbackup_home that permits users to back up just their home directory. There's scdbackup_sys that permits a backup of the system. There's also just an scdbackup that can be fed arguments about which directories to back up and which to exclude from backup. Some backups (home directories, for example) are backed up as filesystems. Others, such as the system backup, are done as afio archives. Simplyfied CD Backup handles multivolume backups as well as single CD backups. Requires: cdrecord, mkisofs, bash, afio.
This small Perl program will allow you to take mail and bounce it back where it came from. It also permits you to include a custom message. While a message can be bounced at any time, it doesn't make much sense to bounce it back hours later, thus procmail is suggested as an easy way to bounce the mail, although any program, even a command line, can be used. Requires: Perl, procmail (suggested).
I had a difficult time selecting between two excellent packages I continue to use. And while I think E*Reminders merits mention, I chose tknotepad. I'm not sure why this hasn't been more widely adopted, but it provides Windows refugees a familiar haven. This tool looks, acts and works just like the Windows notepad. In fact, it's what I use to write this column, and it could be used to write web pages, edit configuration files and much more. Easier for most than my favorite editor, vi. Requires: Tcl/Tk.
Until next month.
David A. Bandel (firstname.lastname@example.org) is a Linux/UNIX consultant currently living in the Republic of Panama. He is coauthor of Que Special Edition: Using Caldera OpenLinux.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
Join Linux Journal's Mike Diehl and Pat Cameron of Help Systems.
Free to Linux Journal readers.Register Now!
- Google's SwiftShader Released
- SUSE LLC's SUSE Manager
- My +1 Sword of Productivity
- Interview with Patrick Volkerding
- Managing Linux Using Puppet
- Murat Yener and Onur Dundar's Expert Android Studio (Wrox)
- Non-Linux FOSS: Caffeine!
- SuperTuxKart 0.9.2 Released
- Tech Tip: Really Simple HTTP Server with Python
- Parsing an RSS News Feed with a Bash Script
With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide