Speeding up global DNS resolution by avoiding CNAMES

As shown in my article “A small CDN for my Mastodon instance metalhead.club,” I like to use CNAMEs to organize my DNS entries. I usually create a DNS record for each host that maps its hostname to the IP. Then I use one or more CNAME entries to link certain (sub)domains to these CNAMEs depending on the service and purpose. This helps with overview and can make organization easier—especially if IP addresses for hosts need to be changed.

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Creating my own small CDN for my Mastodon instance metalhead.club

Since the big Twitter wave that flooded the Mastodon network and, more broadly, the Fediverse in the fall and winter of 2022, international users have been playing a bigger role for metalhead.club. The service is hosted entirely in Germany, and that was still the case until recently. However, with the increasing number of international members come new challenges: for example, the rapid delivery of content. As long as users are mainly located in Germany and Europe, latency times to the “Full Metal Server” in Frankfurt are low.

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Icinga DB fails after update

Since I have been using Icinga DB (instead of just PostgreSQL) as the backend for my Icinga2 instance, it has happened to me twice that Icinga no longer worked correctly after an update of the Icinga DB package. On closer inspection, it also becomes clear why:

× icingadb.service - Icinga DB                                                                                                                                 
     Loaded: loaded (/lib/systemd/system/icingadb.service; enabled; preset: enabled)                                                                           
     Active: failed (Result: exit-code) since Wed 2025-01-22 21:42:50 CET; 27s ago                                                                             
   Duration: 13ms                                                                                                                                              
   Main PID: 1853805 (code=exited, status=1/FAILURE)                                                                                                           
        CPU: 13ms                                                                                                                                              

Jan 22 21:42:50 monitor systemd[1]: Starting icingadb.service - Icinga DB…                                                                                

Jan 22 21:42:50 monitor systemd[1]: Started icingadb.service - Icinga DB.                                                                                   

Jan 22 21:42:50 monitor icingadb[1853805]: Starting Icinga DB daemon (v1.2.1)                                                                               

Jan 22 21:42:50 monitor icingadb[1853805]: Connecting to database at 'pgsql://icingadb@localhost:5432/icingadb'                                             

Jan 22 21:42:50 monitor icingadb[1853805]: unexpected database schema version: v3 (expected v4), please make sure you have applied all database migrations after upgrading Icinga DB
Jan 22 21:42:50 monitor systemd[1]: icingadb.service: Main process exited, code=exited, status=1/FAILURE                                                    

Jan 22 21:42:50 monitor systemd[1]: icingadb.service: Failed with result 'exit-code'.

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Creating a Windows 10 USB boot medium on Fedora / Linux

I recently refurbished a used and old Acer Aspire E774 laptop as a donation for the Computertruhe e.V.. Of course, this also involves overwriting the hard disk with random data so that old data can no longer be reconstructed. Because “deleted” is not the same as “securely deleted”. I used the shred tool in a Fedora Live environment for secure deletion. However, it works just as well with any other Linux distribution.

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T-Shirts for my Mastodon instance metalhead.club

Two things are usually in short supply when you run a Mastodon instance: Funding and public attention. But both are important so that the instance can continue to operate and - if desired - achieve growth or reach. My goal with metalhead.club is to offer a professionally hosted platform for everyone who feels at home in the metal music genre. In order for such a theme-based instance to be viable and its users to benefit from it to the greatest extent, it must achieve a certain level of popularity.

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