2025-08-20
Welcome trixie!
Debian 13 (trixie) has been released on 2025-08-09. So up to upgrading! What could possibly go wrong?
to do ...
I did upgrade my main workstation at home a few weeks before the official release. Everything worked nicely. Of course, noone is going to port my electronic projects from KiCAD version 5 or 6 to version 9. That is to be left for lengthy winter nights, or so it seems. But everything I use daily (sway, foot, emacs, bash, firefox, ...) worked without a hitch.
or rather not to ...
So on to new adventures? I do have small APU2 system (single board computer) running as a gateway/server. It provides a number of services for my home network, like dhcp, dns, ntp etc, see [a]. Nothing is of utmost importance, or so I thought. But then this time I destroyed two services with the upgrade in a "what could possibly go wrong?" moment of insufficient attention.
... dovecot
The upgrade helpfully listed, that upgrading dovecot from version 2.3 to 2.4 would require a complete rewrite of my configuration due to a fundamental change in file format. But it didn't dawn on me that fundamental means exactly that. So an hour later I threw my hands up in the air and felt like a moron. I did stop fetchmail in an attempt to not increase the damage and look at "Why the hell does postfix not deliver its queued email to lmtpd/dovecot?" tomorrow.
The next day I spent like 4 hours to recheck all the bits and pieces. I managed to see my existing mail store via imapd soon. And no, my email client did not download all emails again --- good! I managed to convince postfix to send outbound emails again. And then I tried to grok the documentation, some examples, and my old configuration. I eventually succeeded to deliver emails locally again. Puh! And after that I switched on fetchmail and everything was good. Except that for the next two days there were no emails coming in at all, so I didn't trust it until after I really saw new messages coming in.
... influxdb
A not so important service are the nice graphs to look at, which display the inside and outside temperature and humidity and stuff like that. However, the corresponding pile of software is quite high:
- A perl script (Yes! perl 5 it is!) does request data from all available sensors periodically and forwards the results via mqtt. The script was running like a charm.
- Mosquitto is receiving those data telegrams and forwards them to interested subscribers. Using mosquitto_sub I could verify the telegrams were indeed coming in. So ok.
- Telegraf is acting as a subscriber to pretty much everything and feeds its incoming telegrams into an influxdb. Here things started to become interesting. Telegraf is not available in the Debian repository, but rather from influxdata.com. I had disabled the coresponding apt source long ago, because I upgraded influxdb as well and that did not work well at the time [b]. However, telegraf did not want to talk to the existing influxdb. Inspection of the configuration files revealed, that version 1 of influxdb had gone to bitly nirvana and is not supported by telegraf any more --- or at least that is how I understood the entry
[[outputs.influxdb_v2]]
in the configuration.
- So please upgrade influxdb to version 2, right? Yes, well. At least I made a complete copy of the existing database store just in case. And the upgrade of the software helpfully displayed a procedure to convert the database using a script. That script looked quite plausible, so on to do the conversion.
That conversion succeeded on first attempt. Turns out that talking to influxdb_v2 needs api tokens. Luckily I knew this concept from elsewhere, so I set up tokens for feeding data (telegram) and reading data (grafana). However, the suggestion to add a user to the old version 1 database prior to conversion does make sense only after understanding, that this would have provided some compatibility with the old query language of grafana. Well, I could throw the new stuff out and redo that conversion, but where is the fun in that?
- Grafana now features a different query language named flux, which looks like a map/reduce scheme at least to my eyes. So I started to convert my graphs. This is not completed, but one thing at a time, please!
This whole endeavour highlighted a few things. Email is one of the most important services for me. Yes I did know that, of course. And those graphs, while mostly boring, are actually being used. That is nice given all the work that went into this a few years back.
To be fair: the whole upgrade worked well given the funny network and firewall configuration. And I do not need to call npm and similar tricks to upgrade the extra universes. I just did not pay sufficient attention to two seemlingly small pieces of information.
As always: Have the appropriate amount of fun!