Want to keep your Eyes healthy? Use Redshift

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If you’re spending a lot of time looking at a screen, you’ll probably want to turn down the blues, to give your eyes a chance: http://jonls.dk/redshift/.

To install, just use your operating system’s package manager (apt, pkg, pacman, etc.) to install redshift. On Ubuntu and Debian, this would be:

apt-get install redshift

Try a few of the following commands, and see which you like better (just run these in a terminal, and kill one before trying the other. It’ll take a few seconds to actually shift the colors on your screen; be patient):

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The Best Introduction to ZFS…ever?

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If you care about your data, you should care about filesystems (the operating system/software abstraction over your storage hardware). If you care about filesystems, you will end up at ZFS: the Zettabyte FileSystem.

It’s basically an incredible piece of technology that can do just about anything that you might need from a storage system: instant snapshots, cloning, “live streaming” of filesystem changes over SSH, bitrot/corruption prevention and fixing (with checksumming), plus all the mirroring and parity features you’d expect from RAID. And so, so, so, soooooooo much more.

Here’s the best way to get started: watch these two videos, in order, and then go play with a FreeBSD system:

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New tutorialinux guide: Getting Started with Linux Containers (LXC)

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A while back, I did a YouTube series on Linux Containers (LXC). If you are (or want to be) a sysadmin or software developer, you need to know about Linux Containers, and understand how to use them. I’ve just written a ~45-page guide to getting started with this useful skill — check it out here! For those of you that want more details (or a link to the original playlist), read on:

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Today I Learned: Migrating from sqlite to Postgres is easy with Sequel

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I spent some time migrating an application from sqlite3 to Postgres today, and wanted to write down a few notes for next time. Here they are!

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Today I Learned: ZFS send/receive is Like rsync, but Developed by a Much More Evolved Species

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If you use ZFS, you already know that it completely knocks the socks off of other filesystems. It prevents and corrects data corruption, gives you incredible flexibility, and basically gives you everything you could ever want from a filesystem. If you use OpenZFS on several systems already, you probably know about the ‘send’ and ‘receive’ commands to do incremental transfer of snapshots between systems.

Here’s a great video on ZFS send and receive, which goes much deeper than most videos into how send and receive are implemented, along with some clever ideas for use cases where send/receive can really save you a lot of time and pain.

Because being able to mimic $50,000 enterprise filesystem replication on your home NAS or your little ‘friends-and-family’ WordPress hosting server is pretty effing cool.

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