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Linux and Unix administration and troubleshooting articles, help and inspiration for freelancers and the self employed, advice on blogging, SEO and earning money on-line.

Not a significant source of information concerning Microsoft products. Primary author is an opinionated Mac OS X and Linux Evangelist.

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May contain liberal opinion, small dashes of politics and some crankiness as well as the occasional grin. Contains Skill Tests, Unix and Linux Consultant Listings and more.

This site is not recommended for total n00bies or real gurus. N00bies may be overwhelmed and true gurus will be bored.

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Most recent posts:

A strangely compromised Linux box

First, there was no attempt to hide any evidence. I could see in wtmp and the secure logs that he had logged in, attained su status, and created a new su user for himself. He then changed root's password. ..

Linux 11/5/2009 Tony Lawrence

When Samba Pigs Fly

Such confidence had I that immediately after hitting send, I left my house to do some errands and when I realized I had forgotten my phone, I didn't even bother to go back for it: everything is under control, all pigs are fed and ready to fly. ..

Troubleshooting 11/4/2009 Tony Lawrence

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Gentle Waves

Some people "got it" very quickly. They understood it so much that they were arguing with the people who didn't get it, saying things, like "No, really, this would have been a fantastic tool to have for the work I used to do!" Others were obviously confused. ..

Web/HTML 11/3/2009 Tony Lawrence

Misunderstanding Wave

There are people who don't understand Google Wave. There are people who don't like Google Wave. There are people who do understand Wave, and people who do like it. Most of those who don't like it just don't understand it, but even a few who do understand still don't like it. ..

Web/HTML 11/2/2009 Tony Lawrence

My first Waves

One of the people happened to be someone I do business with and his appearance reminded me that there was something I wanted to talk to him about. We started doing that in a "private" conversation within the existing wave, but then realized that it was better to spawn it off to a new Wave. That's very easy to do and is an advantage of Wave over Mail and Chat - not that you can't peel off from either, but it's easier in Wave. ..

Web/HTML 10/31/2009 Tony Lawrence

Help, I'm disappearing!

Google Maps insists that my address simply does not exist. Indeed, if I summon up a map of the town, the whole street has disappeared! It's still visible in the satellite view, as is my house and even the golf cart parked in my driveway, but the map view shows empty space. ..

Web/HTML 10/29/2009 Tony Lawrence

Answer the bleeping email

Earlier this week I got email from VMware announcing that I could now order Fusion 3.0 for my Mac. Because I had been a beta tester of this, they offered me a coupon code that was supposed to give me a 25% discount. ..

Employment 10/28/2009 Tony Lawrence

The cure for everything - chmod 777

This is all unnecessary. Most of us who have to deal with the results of misunderstood chmod's wish that users didn't even know that the numeric form exists. There would be far fewer errors if users only knew the symbolic modes. ..

Linux 10/27/2009 Tony Lawrence

Prevent deletion or moving of files

You need to let users create files in a common directory, but you don't want them to be able to delete other's files. Or you've put certain files, directories or symlinks into a user's home directory and don't want them to be able to mess with any of those. What can you do? ..

Linux 10/26/2009 Tony Lawrence

Small is the new big

When I tell people I work from a home office, the reaction is often a bit negative. "How long have you been doing that?", they'll ask, with a strong implication that I must just be "between" jobs. As I've said in other places, you could work for yourself for 50 years, but if you took a job at the Mall just before you died, your obituary will probably mention that: most people don't think of self employment as "real" employment. ..

Employment 10/26/2009 Tony Lawrence

I don't WANT the Internet to forget!

Wouldn't we all be better off if we stopped pretending that we are perfect or even close to it? I'm not saying we shouldn't strive toward no being jackasses, not doing dumb things. I'm saying we should accept that we are human, we do screw up and we and everyone else just need to get over it. ..

Web/HTML 10/23/2009 Tony Lawrence

Plenty of space here

Like many people, my customer doesn't understand spaces in command lines. Unlike most, he's not one to leave spaces out - no, he's more likely to insert gratuitous spaces where none are wanted. For example, in an earlier "scp" command, he had added a space after "john". I had chastened him not to add any spaces unless I specifically said to, so it seemed reasonable to him to think that two spaces in a row would also be an error. ..

Shell 10/21/2009 Tony Lawrence

Setting Maximum Service Connections in Kerio Mailserver

One of the questions I often get is how to set those service limits. For example, how many concurrent https connections should we allow? You could just set it to an arbitrarily high number, but that can expose you to Denial of Service attacks where the machine is so busy with https that it can't do much else. On the other hand, you don't want your users unable to connect becayse you have set it too low. ..

Kerio 10/20/2009 Tony Lawrence

Wicked Smaht

When I went into first grade, I was put in the Retarded Class. I'm sure that's not what it was officially called, but all of us who were in it knew that's what it was, and of course so did every other child and all the teachers. Everybody knew us. We were the misfits, the dummies, the slow learners, the problem kids. This was early 1950's, so in reality a lot of us were dyslexic or had alcoholic parents or other learning disadvantages and disabilities, but paying attention to any of that just didn't exist then. ..

Opinion 10/19/2009 Tony Lawrence

A simple file I/O program in C

I had to write this code sample as part of my work. I am presently reverse engineering the MAPI protocol that MS Outlook speaks to MS Exchange. My work does not so much involve reverse engineering since Microsoft has published the entire MAPI protocol in full detail. ..

Programming 10/19/2009 Girish Venkatachalam

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