The Logitech K810 is a nice keyboard, but it does not work with Ubuntu out of the box. Still contrary to what some websites might lead you to believe, it does work. The following instructions worked for me on Ubuntu 13.10 & 14.04.

1. Start a terminal (terminal 1)
2. Install the tools needed for this walk-through

   sudo apt-get install bluez-hcidump bluez-utils blueman

3. Enable Bluetooth on your Ubuntu machine (you might have a hardware button, don’t forget about that)
4. Start the bluetooth manager (blueman) from your start menu, dash, or whatever other way of starting programs your desktop has
5. Start another terminal (terminal 2) – yep you’ll need two for this exercise
6. Get the K810 into pairing mode by pressing the button on the back of the keyboard and then one of the device buttons on the front (F1-F3). You should see the bluetooth light flashing now.
7. In terminal 1 run

   hcitool scan

   if the K810 is found this should give you something like

   Scanning ...
          xx:xx:xx:xx:xx:xx   Logitech K810

8. Copy the address of your K810 (that’s the xx:xx:xx:xx:xx:xx)
9. In terminal 2 run

   sudo hcidump -at | grep pass

10. In terminal 1 run

    sudo bluez-simple-agent hci0 xx:xx:xx:xx:xx:xx

11. In terminal 2 you should now see the passkey which is a number
12. Type that code on your K810 followed by enter
13. The bluetooth manager should now show the K810.
14. In blueman select the K810 and mark it as “trusted”
15. Now click on Setup and follow the dialog box.
16. Tada, you’re done, you can now close all terminals as well as blueman.

The Function Keys

By default, the function keys (the ones above the numbers row) are assigned to special functions like media control, which I find annoying. – Every time you want to do something normal like Alt-F4 or search via F3 you need the Fn key. Logitech’s windows software on the other hand lets you invert the Fn key. Actually all the Windows software does is to send a certain string of commands to the keyboard, which some clever Linux Guru has reverse engineered and coded into a nice little program, that can be found at  http://www.trial-n-error.de/posts/2012/12/31/logitech-k810-keyboard-configurator/. I’ll again add a step-by-step guide:

1. Optional: Go to http://www.trial-n-error.de/posts/2012/12/31/logitech-k810-keyboard-configurator/ and read about how he did it ;)
2. Install a compiler

   sudo apt-get install build-essential

3. Download and extract Mario’s program

   wget https://blog.chschmid.com/media/k810_conf-v0.1.tar.bz2
   tar -jxf k810_conf-v0.1.tar.bz2
   

4. Compile it

   ./build.sh

5. Run it

   sudo ./k810_conf -d /dev/hidraw<x> -f on

   You will have to replace <x> by the hid number that was assigned to your keyboard. In my case it is hidraw2. Of course there are more clever ways, but just work through the numbers brute force starting with hidraw0. – Mario’s program is clever enough to detect if it’s not the K810.

Apart from some minor owncloud glitches me.chschmid.com is running pretty smoothly right now. It’s doing a great job, both as my server and my Desktop replacement. But I can’t guarantee that it will stay that way. Neither can I expect the hard disk drives (HDD) to last forever nor can I guarantee that some idiots won’t burn down the apartment building by setting their Christmas tree on fire. (Don’t laugh, it has happened to my sister)

Used under CC BY-SA 3.0, originally by Diether

So a backup strategy is in inevitable. Now for the first scenario (a dying HDD) people have come up with a solution known as RAID. However that is not what I am doing. For simplicity, I just copy most of my important stuff from one HDD to another once a day. – Actually the server does this automatically via a cron job file /etc/cron.d/cSBackupLocal

12 4    * * *    root    /usr/local/bin/cSBackupLocal.sh;

which executes a simple rsync script /usr/local/bin/cSBackupLocal.sh that does

# Backup data from first hard drive (me1) to second hard drive (me2)

# GIT - My life and stuff
rsync -a --delete /media/me1/git/   /media/me2/Backup/git

# Music - My other life support
rsync -a --delete /media/me1/Music/ /media/me2/Backup/Music

# owncloud
rsync -a --delete /media/me1/ocdata/ /media/me2/Backup/ocdata

The second scenario (house burning down) can not be dealt with that easily. E.g., with the two HDDs that do the mirroring once a day at the same location, a fire would destroy both. So you have to have a copy at some other place.

My most important things (about 20 megs) I have in an encrypted archive that is synced to Dropbox. Things like my Keepass file and Scans of important documents. – You are right, they might give that file to the NSA or something, but as it is encrypted they’ll chew on it for a while.

The only viable solution for my more extended remote backup is to have an external hard drive, that I bring for doing a backup every now and then. When it is not plugged into my server for backup it is stored away safely somewhere else. – As in not within a 5 km range of my apartment. Obviously this system has flaws, like if there is a fire the day I do the external backup, I am still screwed. – But I guess that is as safe as it gets.