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Aerospike February 2024 Meetup at Adjust Berlin office

On Wednesday, February 21st, Adjust hosted the second Aerospike Meetup in their Berlin office. About 50 visitors showed up, which demonstrates a huge interest in the Aerospike database technology.

Install Firefox PPA version over Snap version

It was time to update my laptop, and I already knew that the update will bring Snap, and installs the Snap Firefox version. Along with many known problems.

Using fail2ban to block unfriendly web requests

Every time I peek into the webserver logfiles, I find quite a few 404 requests trying to figure out if certain exploits exist on this server. Now I get that these are automated attempts, and the number of requests coming from one IP show that they try several different exploits and path names. Nevertheless I thought that I don’t need this in my log, and on my webserver. fail2ban for the rescue.

How to configure notifications in Icinga2 Director

I'm using Icinga2 for a long time, but recently installed a new system and using Director for the first time. I know how to configure notifications in Icinga2 config files, but getting them working in Director (with Director options only) is a bit of a challenge. Here is a step-by-step to get simple mail notifications working. From there it should be easier to configure more advanced notifications.

Restic backup

Was asked quite a few times how I do my backups with Restic.

For more than 10 years I was using “Duplicity” for backups, but in 2019 I changed to Restic. The main reason for the change was that Duplicity still can’t handle “Big Data”, as in: larger directories. In 2009 someone opened an issue on the Duplicity bugtracker, and this problem still exists as of today. For about two years I was shifting around the problem, excluding files, trying to make the sigfile smaller. But at some point I decided that it is enough and I need to change the tool.


Text-to-Speech in openHAB

In my ongoing endeavor to improve our home, a while ago I added a notification when the washing machine and the dryer are finished. The notification is send to a Telegram channel. Over the summer vacation I added a number new ChromeCast Audio devices (Google no longer offers the Audio CC, if you need one get one now). One is placed in the kitchen. Not only can I listen to music while eating breakfast, I can also output notifications, by using the CC as an audio sink in openHAB.

To make that useful, I decided to use a Text-to-Speech system. openHAB offers a couple different TTS systems, however most of them need a cloud integration, and therefore a working Internet connection. The “Pico TTS” works standalone, and was my favorite choice for this implementation.


Install a Raspbee II on a Raspberry Pi

A while ago I got a recommendation to look into a Raspbee (from dresden elektronik) as Zigbee gateway. That looked like fun, therefore I ordered one of the devices. The first step is the installation of the Pi itself and then the software for the Raspbee.


Restic upgrade on Debian Buster

A while ago I switched backups from Duplicity to Restic. About time: I was using Duplicity for many years (I think I started using it around 2010, long before Restic became available) and it served me well. But recently I ran into more and more issues, especially with archives getting larger and larger. There is an 11 years old open bug in the Duplicity bugtracker, which describes a showstopper for backing up larger archives. And it doesn’t look like this will be solved anytime soon. Therefore it was time for something new.

Since I’m rolling out my backups with Ansible, it was relatively easy to create a set of scripts for Restic which use almost the same infrastructure as the old Duplicity backups. That works as expected on all our laptops. But the Raspberry Pi, which does the fileserver backups, seem to had a problem. Backups took way longer than before, jumped from 30-60 minutes (depending on the amount of changes) to constantly around 10 hours.


Disable screensaver for Raspberry Pi

The 7" Raspberry display in the kitchen is nice, but unfortunately by default the installation comes with a screensaver enabled. After a while, the display goes dark. No one wants to stare at a blank display, and touch the screen in order to see crucial information.


Replace and re-add a failed drive to a Linux software RAID

Most of my systems run on a software RAID 1 configuration (that is, two disks, where each disk is mirrored to the other). This way, one of the disks can fail and still all the data is available.

If a disk failure happens, the disk is replaced with a similar disk, and then needs to be configured and re-added to the RAID.