The Bad Data Shutdown

I’m a car guy. I like cars, I like driving, and I’ve spent a lot of time and money over the years on vehicles. I’ve swapped and enjoyed a few dozen automobiles as part of my life. If you are on Twitter, you might occasionally see @BrentO and myself go back and forth on some car topic, usually Porsche related. This usually results in an hour or so of life wasted on dreaming of a new car (including getting distracted while writing this piece and pasting that last link in, where I spent quite some time drooling over the Macan).

Recently there was an issue with the navigation system in Lexus vehicles. Apparently bad data was sent during a software update, which is not exactly what you want to happen in a car. I’ve had a few modern vehicles, some of which would be quite handicapped if they onboard computer were frozen or rebooting. In my current vehicle, this would cause issues with climate, navigation, entertainment, and potentially other systems. After all, I suspect many things from door locks to speed control are all integrated together. Certainly the drivetrain is as an open door will automatically shift my car from drive to park, at least at low speeds.

As we move to more drive by wire, bad data or bad software that disrupts the computer systems could be very dangerous. It’s not just updates, but this could even be some internal Denial of Service issue from a USB device or bluetooth connection. In this case,  Lexus acknowledged the problem, which I’m glad to see. The Internet ensures that problems can be reported from many users quickly and very publicly. That makes it hard to deny a widespread problem.

Delivering updates across wireless links is great. It’s cheaper for everyone, saves time, and owners appreciate convenience. However, moving to this model often requires some sort of continuous delivery (CD) process, which should also allow for rolling forward, and releasing fixes for problems. However, if the updates you deliver cause the system to cease functioning, then this doesn’t help. At the last, your QA system needs work and you don’t have a well designed software delivery process.

Various companies are getting better at delivering updates to our systems without downtime, but there’s still work to be done. The smaller your domain of clients, the easier this is. For many of us that work on small systems, an application server or two and a database, we can certainly get much better at ensuring our updates are tested, and more importantly, that we can quickly deploy a second patch if we find an issue. That requires engineering a process that is known and stable, with the ability to respond quickly. For larger systems, with many clients, you need a really solid engineering and deployment process.

Above all, however, no matter what your deployment mechanism for updates, you need to be sure that any data you include is at the quality level you’d expect would be delivered to you.

Steve Jones

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About way0utwest

Editor, SQLServerCentral
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