Solving macOS Error -69784, “Unable to create Core Storage Logical Volume Group”

FileVault’s full disk encryption is a really nice feature of macOS, and making a bootable full-disk daily backup of your Mac’s internal hard disk or SSD using Carbon Copy Cloner or SuperDuper! is a great way to avoid downtime if your internal hard disk dies. You just reboot from the backup drive and get back to work, having lost at most 1 day of work.

However, you may encounter trouble when trying to create an encrypted bootable volume on your external backup drive. I had no trouble finding helpful articles to tell me how to reformat the external drive as encrypted, or even to convert the disk non-destructively to an encrypted volume, but none of them actually worked. In every case, the UI was happy to say it was gonna encrypt the drive and even gave me a recovery code and took a passphrase for the encryption, but then failed with the following message:

Unable to create Core Storage Logical Volume Group.

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Making macOS High Sierra 10.13.1 work with 2 displays again

I have a Mac Mini (“Late 2014″) hooked up to an Asus PB278Q 27” display and a Dell 2405FPW display. This setup has served me well for two years, but today the Mac stopped talking to the Asus monitor for some reason. After some fiddling, I was able to fix it.

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Fixing a Mac Fusion Drive that Disk Utility can’t erase

My Mac Mini w/ Fusion Drive (that’s a hard disk and an SSD pretending to be a single volume for better performance) froze and wouldn’t boot. Nothing would make it boot normally again. Recovery mode was OK but couldn’t erase the boot volume nor mount it via Disk Utility (I just got “Unable to delete the core storage logical volume”), so reinstalling seemed impossible.

Fortunately, I figured out how to do it, using some help from a StackExchange post I found. See below for the details.

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Why Software Development Methodology Adoption Fails

Organizations often try to adopt a software development methodology, in hopes of reducing the risk of cost and schedule overruns in their software development project. Veterans of previous methodology adoption attempts roll their eyes or actively resist, while less experienced team members drool in anticipation of some order and predictability. In this post I describe how software development methodology adoption efforts can fail, based on my own experiences.

This is a personal perspective, so it doesn’t go back all the way to the early days of computer science. It starts when I started paying attention, which was in the 1990s. Nevertheless, I think it’s pretty accurate with respect to what was going on in the 1990s through today (late 2015).

Here goes.

Once upon a time, in the final years of the 20th century, there were some experienced software folks who had been through some successful projects and some failed projects, who had developed a sense for what to do and what not to do in certain situations.

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Why security is hard, and why it’s not going to get easier

Bruce Schneier summed it up well: the good guys have to secure all the doors and windows; the bad guys only have to find one. In a nutshell, that’s why security is hard. Real-world security has to deal with that problem all the time.
If you think of writing software as filling a feature space, sometimes you accidentally provide functionality that you didn’t intend to, while providing what you meant to. You meant to provide an exhaust port but you also created a vulnerability.
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