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Boy, what a roller coaster! Shortly after opening a position for a Senior Devops engineer, we had a funding “event” and now the opening’s gone. What’s worse, I had to lay off one of my developers, right before before the end-of-year holidays. It was stressful for all involved.

We’re doing some interesting things with name relationships at work, and these present fun development challenges. I’m trying to spend as much time as possible in Emacs, because the less-fun work issues always occur when I’m not coding.

I upgraded our codebase to version 3 of Celery, just to get us off version 2. I’m still hankering to replace Celery, but it must have known it was living on borrowed time because it’s been behaving lately, so I’ve decided to fry some bigger fish. But the moment Celery starts acting up again…

I just turned 55. How the hell did that happen?!?


This week, I switched our systems-level monitoring from Cacti to Munin.

I was dissatisfied with Cacti’s interactive-only configuration and limited OOTB charts, and its reluctance to correctly display the processor %U of my multicore servers. I tried the oft-cited suggestion of cloning the existing %U graph into a new template and bumping the maximum to 1,200% (for a 12-core server); no good.

I have a, “I have bigger fish to fry” mindset lately, and I want something that does (mostly) the right thing OOTB without having to delve into the source code.

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My wife owns a NOOK Simple Touch with GlowLight.

Our home router in an Apple Airport Extreme, the latest model.

The NOOK worked flawlessly when she first got it. But starting three weeks ago, it forgets our home network credentials about once a week.

Nothing’s changed in our network configuration. The Airport’s location hasn’t changed. No other electronics in the house have moved. We don’t have any new electronics.

We asked for help at the Barnes & Noble on Pine Street. The help desk person said, “Gee, it hooks up to our network just fine, so, it must be your wireless router.” She was not helpful.

Nothing else in our house has network connectivity problems! Not my personal MBP, my work MBP, my wife’s iMac, my iPad, or our two iPhones. Only the NOOK has a problem.

I wonder if its NVRAM (or whatever it uses to remember network credentials) is sick. But this thing is only a few months old.

No, I don’t have network sniffer software, nor do I want to download a sniffer and learn out to use it. I shouldn’t have to resort to that for an e-reader.

Sigh.


Sometimes you don’t write unit tests. Your reason for not doing so always falls into one of two categories.

Complexity

The code you just wrote would be so much easier to test using system-level testing. For example…

  • The setup and teardown would be 10x the test code.
  • There’s too much interaction with multiple data stores or third-party vendors.
  • Your dev boxes or CI server don’t all have the necessary technology installed.

These are rational reasons to not write unit tests for new code. You’re fine.

Simplicity

But sometimes you don’t write unit tests because the code you just wrote is so darn obvious.

It’s really simple. It’s straightforward. It’s nearly trivial. Why both writing unit tests for it?

Well, I’ll tell you why you should test it. In fact I’ll give you three reasons.
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I’m playing more with Noteshelf and thinking about how I use a whiteboard. And I’m noticing aspects of my sketching for the first time…

My drawings mutate a lot as I create them:

  • I’ll start out leaving space for objects (e.g., server boxes, database symbols), and then decide the objects need more space. (For practical or esthetic reasons.)
  • I’ll assign colors to different entities, and later change the color assignments.
  • I’ll start recording attributes A, B, and C for state transitions, and then decide to drop B and add attributes D and E.
  • It’s very rare that nothing has to change. But even then, I’ll wish I could move the whole diagram on the whiteboard or page in toto, because it’s grown in a direction or to an extent that I didn’t anticipate.

I often wish I could do a diagram twice — once as a dry run, once “for real.”

These alterations happen more often to my drawings than they do for others. At least, it seems that way to me.


I often need to diagram things at work. It’s usually something like a system block diagram, a gnarly code problem, or client-server interactions. Sometimes it’s just a list of things I’m comparing.


Whatever the diagram is, I need to the keep it around for a while. And refer to it, scribble on it, and update it. And sometimes share it.

Since “back in the day,” I’ve used a whiteboard for this. Or sometimes pages from a pad of graph paper. I’ll noodle around, sketch things out, and leave it up.

For sharing, I’ve resorted to snapping a photograph of the whiteboard with my iPhone. (Or a couple of photographs, which I then stitch together with AutoStitch.) If the photo’s not adequately square, I straighten it out with Genius Scan. And then e-mail it. The mail message can get pretty large, so this can be a nuisance.

Eventually the whiteboard needs to be erased, or is accidentally erased. Or I lose the graphing paper doodles, or decide to throw out the diagrams.

In December, I received an iPad 2 as a gift. And I’ve gotten around to thinking, why not step up my game and use the iPad for this? (Yeah, I’m being dramatic and rhetorical. Sorry. I’ll re-phrase: “I’ve decided to use the iPad for diagrams and simple drawings.”)

I haven’t completely figured out how I’ll do this. I’ll write about my experience here as I go down the learning curve, mistakes and all.
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I’ve got an odd problem. I create a 4 GB VM in the Rackspace Cloud with an Ubuntu 11.04 server image. After it’s created, I can’t ssh to it, and ping returns zero bytes.

I can get to it from the Rackspace dashboard console. But it’s not on the network. Creating a VM without a network is kind of useless.

I first alerted Rackspace to this over a week ago. It’s still present in our VMs, and now impacts our company in a very serious way. Rackspace says their Operations team has to check the host machine to fix this. You’d think this would be easy to isolate and resolve, but….nope.

Does anybody else have this problem?

———

Update: Rackspace confirmed this is a system-wide problem! Until it’s fixed, after I rebuild a VM I have to ask their customer support to goose the underlying host machine before it’ll respond to the network. Yikes.

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