Developer : What helps you picture a system?

Systems are complex things, they contain many components, from the physical to the ethereal software running around inside them, you have many considerations, from load to speed and timing, to ease of access and security, so many skills and so much to consider...

So how do you go about creating such systems?

I've had a wealth of experience, in different industries, which arm me with some hard earned experience of how I can best filter through all the complexities before committing too far in the wrong direction, and even more experience of how to rescue a system already too far in the wrong direction!

But as a new developer, a new system guy, or just an experienced guy joining a new team, how do should one best go about approaching the task at hand?

Here are my top tips...

1. Always listen, take notes, record or otherwise pin down the specification.... Walk and talk to the people asking for the system, get to know their mind-space as best you can.

2. Think before you act, many experienced developers take time to think of a solution, they'll diagram, discuss, brain storm or just walk through a problem.  These mental acrobatics are sometimes key to a project getting off on the right footing.  Younger, eager, developers often over look having a period of quiet contemplation.  Don't mix this up with not implementing the basics, an XML loader or a generic piece of code can be written, but what those general tools are put to use doing, the actual architecture, that needs thinking about.

3. Discuss the system, from top to tail.  If you're handed a spec, dissect it, talk to the author, talk to the target customer, talk to the developers who are going to lash themselves to the mast and go along with this vessel, whether it were to sink or sail.  Discussion is not thinking, from the previous point, you need to think your own path through the problem, and remember your path maybe different to others, your solution maybe different to others, this next tip to discuss the problem lets you exchange with others and ensure you are both reading from the same story sheet.

4. Repeat.  Once you have started to work, record what you are doing, talk to others about what you want to do, discuss how things are going and feed all this back into a new round of work, the next sprint, the next deliverable...

These are my positive tips... Have I got negative tips?... No, I have experience, and sadly I can't pass that onto you directly.

Story Time : Fantastic Rack Mount Mistakes #2

Nothing is going to compare to the first post I made in this little series, but this was the first server room moment I had had to deal with.

I started work at a location, not very far from where I live now, and there was a little server room, again an old NCR mini-computer but this time it was running a custom cut of SCO-Unix, this machine was important, it handled everything for the whole midlands operation of this company.

And it was my first day...

There was a rack with kit on the right, and a rack with kit on the left, and you walked down the gap in the two... This was particularly bad, as it left you no room to move in there.

I was being shown around by the previous guy, whom was leaving, and I was really nervous... (Jim if you're out there, I hope you remember this).

So, we'd just concluded the tour of the server cupboard when I noted a black fleck in the air flow around me, another and another.  "Jim, there's black stuff".

Before I had the words out my mouth we got an awful smell of burning, everything was still on though.  All the network switches, the minicomputer, the UPS's the PC's running MSMail... Everything was still on, even the CRT monitors....

Something was certainly going wrong through, Jim stepped to the top of the room, leaving me in the middle isle, and he slid down the back of the rack and took a look, suddenly his arms were up and he's pulling the cables from a CRT monitor, and he yanks it down, it's clearly burning!

I pull the side door open and he skittles this thing down the corridor where it comes to a halt, happy it's not in the server room and not actually burning up we turn back to see what mess has been done.

The air has already been filtered so the soot removed, everything looked fine.  Except, unspotted by myself (I was only a few hours into this role) there was a little warning light on one of the UPS's, warning that it was on battery only.... I missed it, Jim missed it... Don however didn't miss it, as suddenly at the main door Don skidded into view, and nearly body tackled the pair of us inside the room, as he was down on his hip pulling at the mini computer.

"There's no power!"

The minicomputer was still on, but pressing a key on a terminal it was reporting it was busy shutting down.  The UPS was warning it had low power.... The company was offline.

Everything stopped... from ray role to purchasing, stopped.  Over 200 people, stopped.  COSTLY!

What had happened was as Jim had gone around the back, he'd stood on a cable, the mess of cables to be honest, behind the rack.

And one of them was the female to male coupler for the UPS to the wall, the plug was still in the wall, disappearing into the mess of cable, and then a cable emerging and plugged into the UPS, so it looked fine... and the UPS was connected to the minicomputer, with nice screwed in connectors... Hard to remove.

But this coupler was just laying there in the morass, and it was hard to see, and it was not screwed together at all... And it had come loose.

Needless to say, Jim was never remembered for saving the room from the fire, but remembered for unplugging the minicomputer.