The plan was to run a Postfix secondary MX inside a docker container.
Below are many links that might help me to get that going.
For now, I think this is the shortlist of solutions to try:
- Docker Mailserver
- Mailcow
- Mailu
Some notes on running Postfix inside a docker container
Posted by jpluimers on 2025/11/14
Posted in *nix, *nix-tools, Cloud, Communications Development, Containers, Development, Docker, Infrastructure, Internet protocol suite, Kubernetes (k8n), postfix, Power User, SMTP | Tagged: 254, 29, 52, 787, DMARC, domains, set | Leave a Comment »
Best 404 page ever? : ProgrammerHumor
Posted by jpluimers on 2025/11/13
While doing some ASCII art blog-post drafts cleanup, I bumped into the (now deleted) [Wayback/Archive] Best 404 page ever? : r/ProgrammerHumor which pointed to the (also now deleted).
I got there via my (not deleted!) blog post Why I like PlantUML.
So I dug up the old archived copy of that PlantUML 404-page and made gist out of it.
I soon realised this was all encoded stuff, seemingly a mix of a ROT13 variation and some other shifting around.
Luckily the original page mentioned in the Reddit post was way easier, so I put that in a gist too.
Bot are below the blog-signature. Enjoy!
Oh, and the full text of course above the signature:
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Posted in ASCII, ASCII art / AsciiArt, CSS, Development, Encoding, Fun, HTML, HTML5, JavaScript/ECMAScript, Scripting, Software Development, Web Development | Leave a Comment »
2023 PDF special voor alle leden: GUI’s programmeren met Python | MagPi
Posted by jpluimers on 2025/11/13
[Wayback/Archive] PDF special voor alle leden: GUI’s programmeren met Python | MagPi
Via: [Wayback/Archive] MagPi Nederland on Twitter: “PDF special voor alle leden: gui’s programmeren met python #raspberrypi #python”
Download:
[Wayback/Archive] https://www.magpi.nl/files/attachment/35 (202209131320GUI NL.pdf).
Guizero: Read the rest of this entry »
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Posted in Development, Hardware Development, Python, Raspberry Pi, Scripting, Software Development | Tagged: Python, RaspberryPi | Leave a Comment »
This is nice #geekporn. ASCII Art that’s truly useful.…
Posted by jpluimers on 2025/11/12
I forgot both to archive this 10+ year old G+ post and schedule a blog post about it This is nice #geekporn. ASCII Art that’s truly useful.….
ASCII to bezier drawn images in a very clever way.
Found it back when searching for prior blog posts on ASCII art, because of my yesterday’s blog-post ASCII Art Archive, so here it finally is: the links about how to go from ASCII art to bezier images. Have fun!
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Posted in .NET, ASCII art / AsciiArt, C#, Delphi, Development, FireMonkey, Fun, ObjectiveC, Ruby, Software Development | Tagged: geekporn | Leave a Comment »
roehling/postsrsd: Postfix Sender Rewriting Scheme daemon
Posted by jpluimers on 2025/11/12
This finally made me perform the (long overdue) migration from Sendmail to Postfix:
The Sender Rewriting Scheme (SRS) is a technique to forward mails from domains which deploy the Sender Policy Framework (SPF) to prohibit other Mail Transfer Agents (MTAs) from sending mails on their behalf. With SRS, an MTA can circumvent SPF restrictions by replacing the envelope sender with a temporary email address from one of their own domains. This temporary address is bound to the original sender and only valid for a certain amount of time, which prevents abuse by spammers.
[Wayback/Archive] roehling/postsrsd: Postfix Sender Rewriting Scheme daemon
Via a long queste to figure out why Gmail every now and then bounces forwarded messages because of Sender Policy Framework (SPF). Below are a few of the links that brought me here in mostly reverse order, but first some links that should help me further on the topic of Postfix virtual aliases.
The sendmail setup had some features not covered below (like a catch-all forward for email to addresses virtual domains not covered by a virtual alias) which I hopefully can cover later.
One thing learned both over the past decades and related postfix material: use separate servers or containers for each of your functions. So do not mix web-hosting, outgoing mail, incoming mail, fail2ban and others on the same server.
Links:
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Posted in *nix, *nix-tools, Communications Development, Development, Internet protocol suite, postfix, Power User, sendmail, SMTP | Tagged: Reload | Leave a Comment »
ASCII Art Archive, my own ASCII signature, plus many FIGlet and TOIlet ASCII font art links
Posted by jpluimers on 2025/11/11
Earlier this year I bumped into [Wayback/Archive] ASCII Art Archive
This brought back instant memories about ASCII art, so in the future expect af few unfinished blog-posts that were in my “if I ever get to it archive” about it.
Let me start with my very limited ASCII art I used in late 1980s and early 1990s newsgroup and LISTSERV mailing list signature I reconstructed from a comp.virus post¹ having some very old contact data²:
o _ _ _ _ _ voice: +31-2522-20908 (18:00-24:00 UTC)
/ (_' | (_) (_' | | snail: P.S.O.
__/ attn. Jeroen W. Pluimers
P.O. Box 266
jeroenp@rulfc1.LeidenUniv.nl 2170 AG Sassenheim
jeroen_pluimers@f521.n281.z2.fidonet.org The Netherlands
Shortly after that, my main source of income moved from the command-line to GUI based tools, so I temporarily kind of lost interest in command-line tools and customs. In that period FIGlet (see below) got created, which I totally missed (though I vaguely remember the 1.0 version being named newban).
The link at the start of this blog post not only pointed me to FIGlet, but also has a lot of examples (like some [Wayback/Archive] ASCII Art Logos – asciiart.eu) of which many by ASCII artist Joan Stark, and also links to JavaScript based tools:
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Posted in ASCII art / AsciiArt, Development, Encoding, Fun, History, JavaScript/ECMAScript, Retrocomputing, Scripting, Software Development | Leave a Comment »
LinuxCND: The Raspberry Pi that ships other Raspberry Pis – Pi Australia
Posted by jpluimers on 2025/11/11
Cool practical application of LinuxCNC: [Wayback/Archive] The Raspberry Pi that ships other Raspberry Pis – Pi Australia
LinuxCNC controls CNC machines. It can drive milling machines, lathes, 3D printers, laser cutters, plasma cutters, robot arms, hexapods, and more.
Via [Wayback/Archive] Frans van Berckel on Twitter: “@geerlingguy So, there is a Raspberry Pi, that ships other Raspberry Pis?”
–jeroen
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Posted in *nix, *nix-tools, Development, Hardware Development, Linux, Power User, Raspberry Pi | Leave a Comment »
Thomas Fuchs: “For the love of Eliza, stop using AI-generated images for blog posts and articles …” – Hachyderm.io
Posted by jpluimers on 2025/11/10
[Wayback/Archive] Thomas 🔭🕹️: “For the love of Eliza, stop using AI-generated images for blog posts and articles. It’s like serving some nice vomit as a side dish with your lovingly prepared homemade dinner.…” – Hachyderm.io
--jeroen
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Posted in AI and ML; Artificial Intelligence & Machine Learning, Development, Generative AI, LLM, Software Development | Leave a Comment »
How to monitor USB power consumption? – Ask Different
Posted by jpluimers on 2025/11/10
TL;DR: it is impossible on a Mac to accurately measure power usage by attached USB devices. Only a general indication is possible, but it is unreliable.
[Wayback/Archive] How to monitor USB power consumption? – Ask Different
- System Profiler needs manual refresh and is a very rough indication
- iStatMenus is a graph, but not very accurate
- Activity Monitor is even rougher than the above
Related: [Wayback/Archive] View energy consumption in Activity Monitor on Mac – Apple Support (UK)
Via: [Wayback/Archive] macos view usb power usage – Google Search
–jeroen
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Posted in Apple, Mac, MacBook, MacBook Retina, MacBook-Pro, Power User | Leave a Comment »
When Spotlight fails to find some files: mdutil revisited
Posted by jpluimers on 2025/11/07
On my M1 MacBook, somehow Spotlight started to fail returning some indexed files (especially recently added ones would not show up or it would take a very long while for some of them to show up).
So I revisited mdutil and related commands while writing a comment on the YouTube movie [Wayback/Archive] How To Rebuild the Spotlight Index on Your Mac – YouTube which since then vanished, but luckily I saved it and here I amended it with formatting:
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Posted in Apple, Mac, Mac OS X / OS X / MacOS, Power User | Leave a Comment »
The Wiert Corner - irregular stream of stuff 