HAProxyConf 2019: Inspect, Control, Report: HAProxy as the SRE’s Door Man

In November 2019 I spoke at HAProxyConf in Amsterdam about how we at CenterDevice use HAProxy to protect backend servers from malicious users and log information that is vital during troubleshooting. HAProxy ACLs serve to classify unwanted traffic, including vulnerability scanners and spam bots, and then HAProxy deny rules filter traffic. Moreover I talk about how HAProxy gives us detailed logs and metrics, which we visualize using Grafana, Elasticsearch and Kibana, and how we employ DNS service discovery to automatically configure load balancing to backend servers.
Conveniently the HAProxy folks have provided a full transcript of the presentation, as well as a recording. To read along, visit the HAProxy User Spotlight Series page

Schoko Toffee Cookies

Nachdem ich zufällig über das YouTube Video zum “Brown Butter and Toffee Chocoloate Chip Cookies” Rezept von “bon appétit” gestolpert war, habe ich heute die zweite Ladung Kekse produziert. Da das Rezept mit amerikanischen Maßen hantiert, und ich heute erneut leicht genervt Cups und Butter-Sticks umzurechnen hatte, lohnt es sich wahrscheinlich, das ganze einmal mit hierzulande gebräuchlichen Einheiten zu reproduzieren. Die Umrechnung ist nicht exakt so, wie man sie in den typischen Tabellen findet, sondern auf etwas "glattere” Werte gerundet. Bisher sind allerdings noch keine Klagen hinsichtlich der Ergebnisse gekommen :) Das Rezept reicht für etwa 30 Cookies.Zutaten200g Brauner Zucker60g Weißer Zucker250g Mehl (Type 550)250g Butter (keine Margarine)2 Eier (M)1 Päckchen Natron (entsprechend 1 Teelöffel)1 Teelöffel Kochsalz für den Teig1-2 Esslöffel Salzflocken für die Dekoration200g dunkle Kuvertüre2 Rollen “Rolo” Karamellbonbons1 Vanilleschote oder ca. ½ Fläschchen Backaroma Van…

Add Custom HTTP Basic Auth Entries to iCloud Keychain

While automatic filling of HTTP basic auth credentials works fine on the Mac, I have had significant trouble getting it to work on iOS devices. This is especially unfortunate, because while on the road I sometimes need to have a look at monitoring systems that have HTTP basic authentication enabled and that use long complex passwords. Should be easy with iCloud keychain, right? Yeah... Opening the respective site in iOS Safari pops up the basic auth credentials dialog. It also shows the little key icon in the keyboard toolbar which gives access to iCloud keychain entries. However, while on the Mac the username and password fields are correctly populated, on iOS you cannot even see the respective entry. Turns out, and I assume this is a bug in iOS Safari, the type of keychain entries shown is limited to "Web form password". Safari on the Mac stores the entry as "Internet Password" though, as can be seen in the Keychain Access application on the Mac:
Knowing th…

Amiga 500 Restoration: A501 Memory Expansion

The previous posts were mostly about cosmetics. This one is more technical, dealing with the repair and some preventative maintenance of the A501 memory expansion card. If you are curious to learn more about the retrobrighting of the computer’s case, don’t worry — I’ll get back to that at a later time.This is the third post in a series about restoring an Amiga 500 back to its former glory. Here are all of them so far. I’ll try to remember to update this in all related entry.2017-12-24: Amiga 500 Restoration2018-01-05: Retrobrighting I2018-02-05: A501 Memory ExpansionAmiga Memory — The BasicsWhen the Amiga 500 was first introduced, it came with 512KB of memory. That was already double the amount the original Amiga 1000 had, but still not a whole lot. Especially when developers started to get familiar with the audio and video capabilities of the machine, RAM became a limiting factor in what you could do. Merely copying a single floppy disk with its 880KB required swapping back and forth…

Amiga 500 Restoration: Retrobrighting I

In part one I described how I got and disassembled an Amiga 500 for a thorough cleaning. This part is about my first attempts to restore the grey/beige color the case had originally had, but over time had turned it an ugly yellow.This is the second post in a series about restoring an Amiga 500 back to its former glory. Here are all of them so far. I’ll try to remember to update this in all related entry.2017-12-24: Amiga 500 Restoration2018-01-05: Retrobrighting I2018-02-05: A501 Memory ExpansionFirst Things FirstDisclaimer 1: It has been quite a while since my chemistry lessons in school, and even though reading up on the details, combined with what I still remember, left me with some confidence of having roughly understood what’s going on, what follows might be woefully wrong, at is guaranteed to be imprecise. So by no means should you use this as the basis for any upcoming exams 😉. Also, I understand the links provided are not scientific publications, so they themselves might be w…