Doctor, I’ve got audit complaints about my kernel log. September 24, 2008
Posted by Garrison in Case Study, Command Line, HowTo, Linux, Ubuntu.add a comment
AppArmor, introduced to Ubuntu with Gutsy, is yet another security tool unleashed upon the infosphere. In part, AppArmor is intended as an alternative to SELinux, which can easily be seen as daunting to configure; unfortunately, many such projects are daunting for those admins forced to walk the plank of unfamiliarity above a sea of expectations. Despite a troubled history, the project seems to be here to stay so it is likely only a matter of time before audit messages crop up in one’s kernel log. For those who find AppArmor unnecessary, unpalatable, or just untimely, herein lies a quick-and-dirty guide for telling AppArmor where to stick its audit complaints. (more…)
When in doubt, test. January 14, 2008
Posted by Garrison in Case Study, Command Line, Debian, HowTo, Linux, Ubuntu.1 comment so far
Shortly after I last upgraded my mail server, one user reported that his mail client was failing to connect with the message:
"Unable to connect to your IMAP server. You may have exceeded the maximum number of connections to this server..."
He was the only one known to be having this issue, so after a cursory check of the server with no obvious problems, I suggested that this might be an error on his end, such as connecting to the secure IMAP port without using SSL/TLS. Occam’s Razor suggests that a server error is more likely than a client error which just happens to coincide with a server upgrade, so I eventually decided to dig up some infrequently used commands and perform a thorough analysis. (more…)
Quick and Easy Caller ID on MythTV December 31, 2007
Posted by Garrison in Case Study, Command Line, HowTo, MythTV, Telephony, Ubuntu.add a comment
I have resisted the urge to display caller id on my MythTV 
as somewhat obvious. I’m always looking for ways to demonstrate the freedom which comes from using open source software, but I prefer the zesty freshness of an original idea rather than anything that’s been done, redone, and done again. My wife, however, thought that Myth caller id sounded like a great idea and asked me to set it up. What follows is how I did this with the least possible effort. (more…)
Linux Bane October 15, 2007
Posted by Garrison in Case Study, Linux, Ubuntu.add a comment
While I was cooking last night’s dinner, I made the mistake of leaving my laptop running, open, and unattended. Because ours is primarily a Linux household (my wife is a Mac user), 
I normally don’t worry much about the computers. The servers, devices, and desktops tend to chug along without needing anything more than an occasional `aptitude update && aptitude upgrade`. Laptops, however, are an entirely different story. As you can see in the photo, we live with a creature that is essentially a heat seeking missle bent on killing laptop computers. Sure it was funny the first couple times, but amusement quickly turned to horror when I saw that she can actually crash Linux. All my base are belong to her.
Multiple Recipient Delimiters in Postfix August 29, 2007
Posted by Garrison in Case Study, Command Line, Debian, HowTo, Linux, Ubuntu.4 comments
Some time ago I enabled recipient delimiters (e.g. user+foo@host.tld) as a convenient way to know if shady web forms are 
contributing to my spam folder. The idea is that when House Depot requires me to have an account before I can see if they have loose screws in stock locally, I can sign up with garrison+housedepot@codefix.net instead of my usual e-mail. With recipient delimiters enabled, postfix will try to deliver any incoming mail to garrison+housedepot but when it finds no such user, it will try garrison and I get my mail. The problem arises when I discover that House Depot’s broken web form rejects any e-mail addresses with “+” in the user name as invalid. I’m already using garrison+foo style addresses elsewhere so I don’t want to change the recipient delimiter, but neither do I trust my real address to a company that can’t even create a proper web form. (more…)
Spam War Chronicles: SARE Ninjas July 17, 2007
Posted by Garrison in Case Study, Debian, Linux, Ubuntu.add a comment
S.A.R.E. Ninjas are the folks over at SpamAssassin Rules Emporium who act as sort of an arms dealer in the Spam War: they publish custom rules and plugins for SpamAssassin, the Open Source world’s powerful anti-spam software. This article is about an imminent software release that promises big trouble for spammers. (more…)
Dell Agress with Codefix June 7, 2007
Posted by Garrison in Debian, Linux, Ubuntu.add a comment
Dell didn’t ask but if they had I would have told them that Ubuntu Linux is a good choice. I have generally refrained from the usual histrionics whenever something Linux-ish makes the news, but I’d would like to voice a couple remarks regarding Dell’s Ubuntu announcement.
While I’m always happy to see Linux reaching a wider audience, Dell has been something of a fair weather friend to the open source crowd. (more…)
