Why Troubleshooting at midnight is not recommended

Note to self:

When switching your smtp service from sendmail to postfix, shutdown sendmail.

It’s rather helpful to do so. Else you’ll spend the next hour trying to figure out why postfix isn’t accepting connections. Especially when you ignore the output of ‘netstat -tlp’ and that the banner for the sendmail service locally lists sendmail and not postfix.

Operating System Perversions

In what might be my greatest operating system perversion ever, I’m using Microsoft’s Remote Desktop Client for the Macintosh on my Macintosh G5 desktop connected to a IBM Tablet PC running Windows XP Tablet edition to install Red Hat Enterprise Linux on a Dell Server using the Dell Remote Access Console (a java application).


Two things going on at work – with myself – that need to be nipped in the bud.

One of the feeds I have in my aggregator is the Creating Passionate Users site. It’s what I’d long to be, and never quite make it. While I can deal without the hokey graphics, the writing is superb, and the ideas deep – each and every time. The feed might hold the record for “most flagged entries in NetNewsWire to read later”

The Death by Devil’s Advocate article hit home for me this week. I’ve done a lot of that in my career – killing ideas, many even my own, by analyzing them to death.

I’m not exactly sure why I do this. I don’t know if it’s an “IT” tendency to keep from over-extending oneself and the infrastructure into some unmanageable mishmash, but an awful lot of ideas get killed by imagining possible negatives. And I’ve been doing that a little too much these past few weeks – it’s the only side I think my co-worker has seen, and too much a side that my boss is seeing. And I don’t like how it looks in the mirror. I need to rip out the negative nabob and pipe it to /dev/null.

I realized tonight that I’m planning these hardware installs like I play SimCity. I never could play SimCity and win with the regular rules. When SimCity 3000 came out for Windows, what I did was find the cheat codes to give me unlimited funds, pause the game, and then I proceeded to build my entire city for hours, and only when I had all the grids laid out perfectly, the roads where I wanted, all of the electric and pipes ran, did I unpause the game and let the city run.

I’ve done similar with the eXtension infrastructure – I’ve bought all the hardware and support equipment (even down to the label printer) – and I’m making sure I understand all of the little things – e.g. the Dell Remote Access Card, the Raid controller, BMC, the Xserve install options, that all my cables and devices are labeled, etc. And while I do plan on making sure I’ve got authentication and backup strategies working before I unleash the rest of eXtension into the infrastructure, what I need to make sure I’m not doing, is building the entire city on pause before I press “Go”. There’s time enough for moving the city around after it’s started growing.

For the record…

I’m actually really enjoying the whole Red Hat thing. I found myself actually spec’ing Intel/AMD hardware today for a tiny little desktop machine that I could run linux on personally and play. Though it’s still too expensive to do a new machine to just play (I’ll just buy my parents a Macintosh at some point and get back their PC and run Linux on it).

Though, I really don’t see myself shifting from the Macintosh on the desktop. In the server room, however, I really forsee a lot more Linux than OS X. And I wasn’t quite expecting myself to actually believe in that. But I’m even more comfortable now with Red Hat (and Sun/IBM/Dell/etc. server hardware) than OS X (and Xserves) in the server space.

However, also for the record, I am thoroughly unimpressed with RPM.

In the Land of the Linux

So, the occasional problem that has popped up for the few eXtension services that we have running at the moment has made me painfully aware how much I’ve delegated over the last few years when it comes to Linux-based services and infrastructure.

It’s not that I can’t muddle my way through it – and have repeatedly in my career. I know the system administration concepts pretty well – and those translate, no matter what platform you are on – even Windows. But I’m an ex-windows programmer and MCSE/CNE that knew enough Solaris, VMS, and Ultrix to be dangerous – and has been running Macintosh OS X on the desktop for three years. Experienced Linux users would (and do) laugh at me. I’ve installed a few Linux boxen every few years dating all the way back to Red Hat 5-ish or so, but never ran it for long as a desktop. And frankly some of the politics of it at NC State soured me on ever wanting to do much with Linux on a personal level – but that’s a story for another (or probably a-never) day.

Thankfully, I had great staff that worked for me that really enjoyed it, because I really was happy to have it our server rooms. And I hope to have that again here, but for now, I’m it – and I needed some kind of crash course in Linux system administration that hopefully didn’t involved crashed systems to cause me to learn what I needed to know.

So, this week I’m taking the Red Hat Rapid Track course for the RHCE. I figured that “rapid” and “crash” meant about the same thing – and that while I don’t really care about getting the actual certification (with the MCSE and CNE back in 1996 – I never got much personal satisfaction out of a “cert”) – I figured the test would help force me to concentrate on absorbing the material.

Up through this weekend, I’ve been pretty paranoid that I shouldn’t be taking this level of the class – I took the pre-req tests and didn’t do all that well on a few of them “Your knowledge of the materials at this skill level is spotty.” So I’ve been a little worried. But I’ve also been a little schizo – because when I go to the bookstore and look at the Linux books in the store – or even the outline for the RH300 class – I know pretty much all the concepts – just not the specifics. Then I start worrying about taking a course, when I could just pick up a O’Reilly book or something and learn what I need on my own.

Well, the first day of training has me feeling a lot better. The instructor is good – the pace is actually a bit slow (I know most of what he’s covering, only to learn the Red Hat-specific commands and file locations – which is exactly what I needed to learn). Over the next few days, I’ll have some observations, but overall, I’m pretty impressed with the course and am glad I’m in it – it gives me a enforced, and controlled environment to learn the things I felt I needed to learn.

I’m also impressed with Red Hat Enterprise Linux version 4 – and I’m especially glad to see some of the new features popping up – like finer-grained ACLs in ext3 – and things like SELinux. (neither of which we covered in much depth – but I’ll be glad when that stuff starts taking root in the next few years).

The Red Hat building itself (the first time I’ve been in it – the headquarters is on the NCSU Centennial Campus) – is interesting – along with our badge we were given a list of “don’t wander around” rules – and there’s all these cold-war esque propaganda posters on the walls. (but hey, this is from a guy that would have posters from Despair, Inc. on the walls).

At the very least, the custom-labelled water bottles are a nice touch 🙂

Removing the Invisibility Cloak

One of my work colleagues asked me a few weeks ago what it took to make /etc show up in the Finder on the Macintosh.

I knew it was some kind of HFS+ invisibility setting – but I honestly had no clue how to change that setting. About the only thing I knew to say was suggest doing a “open /etc” from a terminal window.

Well, thanks to this article at TUAW I learned about the “SetFile” command from the developer tools.

For reasons I don’t completely I can’t seem to get it to work on /etc (which is a symlink to /private/etc in OS X – and /private/etc is already technically visible and the ‘v’ visibility parameter is only a folder attribute according to the SetFile man page) – but I can get a:

/Developer/Tools/SetFile -a v private

to work, executed in a sudo’d shell. And then at some seemingly random point (facilitated perhaps by removing /.DS_Store) the Finder realizes it can see /private

For the record GetFileInfo shows the HFS+ attributes.

(obviously the developer tools should be installed, which you should be doing by default if you are reading this blog and own a Macintosh)