Migrating to Restic for offsite backups.

20201023: UPDATE: Added command to clean the local backup cache.

20200426: UPDATE: Fixed the "pruned oldest snapshots" command.

A couple of years back I did a how-to about using a data backup utility called Duplicity to make offsite backups of Leandra to Backblaze B2. (referrer link) It worked just fine; it was stable, it was easy to script, you knew what it was doing.  But over time it started to show its warts, as everything does.  For starters, it was unusually slow when compared to the implementation of rsync Duplicity uses by itself.  I spent some time digging into it …

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Rigging up Raspbian Buster to run on a Pi-Top

It doesn't seem that long ago that I put together a Pi-Top and started tricking it out to use as a backup system.  It was problematic in some important ways (the keyboard's a bit wonky), but most of all the supported respin of Raspbian for use with the Pi-Top was really, really slow and a bit fragile.  While Windbringer was busy doing a full backup last week I took my Pi-Top for a spin while out and about, and to be blunt it was too bloody slow to use.  At first I figured that the microSD card I was using …

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Pictures from my trip to San Diego, summer 2019.ev

Last summer my day job sent me down to San Diego, CA to attend the Linux Security Summit and report back.  Unfortunately just about all of the content there intersected in no way, shape, or form with anything we're working on so it was largely a dog wash.  I probably won't attend again because, balancing the cost against the information gotten it just wasn't worth it.  I did, however, take a couple of engineers from Oracle for their first good sushi dinner ever, took an amphibious boat tour of San Diego Bay, and hiked along the waterfront for a couple …

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Echoes of popular culture and open source.

(Note: This post is well beyond the seven year limit for spoilers.  If you haven't seen 2001 or 2010 by now, I can't help you.)

Many years ago, as a loomling, one of my very first memories was of seeing the movie 2010: The Year We Make Contact on cable.  That the first 'real' record I ever listened to was the soundtrack to that movie should come as no surprise, but that's not really relevant.  I was quite young so I didn't get most of it, but I remembered enough about it that it gave me some interesting questions (so …

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Summer vacation is rapidly coming to an end.

It seems as if another summer is rapidly coming to an end.  The neighbors' kids are now back in school, school buses are now picking their way down the streets, and due to Burning Man coming up it's now possible to eat in a real restaurant in the Bay Area for the next couple of days.  I've been pretty quiet lately, not because I've been spending any amount of time offline but because I've been spending more time doing stuff and just not writing it up.  I've been tinkering with Systembot lately, adding functionality that I really have a need …

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Accelerating a RAID-5 array with a solid-state hard drive.

A couple of weeks ago, one of my co-workers mentioned in passing that he'd surprised himself by adding an SSD (solid state drive) to his file server at home.  To recap a bit, Leandra, my primary server at home has a sizable RAID-5 array storing all of my data.  However, one of the tradeoffs is that stuff recently written to the array is a little slow to be read back.  It's really not noticeable unless you're logged in and running commands, and even then the lag is something like one or two seconds.  Noticeable but not actually problematic.  At any …

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Linux on the Dell XPS 15 Touch (9570)

UPDATED: 18 March 2019 - External display adapters that actually work with this model (and Arch Linux) added.

For various reasons, I found that I had a need to upgrade Windbringer's hardware very recently.  This might be the first time that a catastrophic failure of some kind was not involved, so it's kind of a weird feeling to have two laptops side by side, one in process and one to do research as snags cropped up.  This time around I bought a Dell XPS 15 Touch (9570) - I was expecting things to be substantially the same, but this did not seem …

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Systembot: Adventures in system monitoring.

If you've been following the development activity of Systembot, the bot I wrote to monitor my machines (physical as well as virtual) you've probably noticed that I changed a number of things around pretty suddenly.  This is because the version of Systembot in question had some pretty incorrect assumptions about how things should work.  For starters, I thought I was being clever when I wrote the temperature monitoring code when I decided to use what the drivers thought were high or critical values for sending "something is wrong" alerts.  No math (aside from a Centigrade-to-Fahrenheit conversion), just a couple of …

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Ansible: Reboot the server and pick up where it left off.

Here's the situation: You're using Ansible to configure a machine on your network, like a new Raspberry Pi.  Ansible has done a bunch of things to the machine and needs to reboot it - for example, when you grow a Raspbian disk image so that it takes up the entire device, it has to be rebooted to notice the change.  The question is, how do you reboot the machine, have Ansible pick up where it left off, and do it in one playbook only (instead of two or more)?

I spent the last couple of days searching for specifics and found …

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Build your own time server with a GPS receiver.

If you've had your ear to the ground lately, you might have heard that the NIST timekeeping radio station used by devices all over the world as a time reference for Coordinated Universal Time as well as some experiments in signal propagation and geophysical event notices might be on the chopping block in 2019, leaving the HF bands quieter and, let's face it, we can't have nice things.  Clocks that rely on this time source signal won't have any way to stay in sync and the inevitable drift due to the imperfections in everything will cause fractions of second to …

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