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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.


Migration from Twitter to Mastodon

Many people (I don’t like this phrase) are leaving Twitter these days, and looking for a new social media home. One of these places is Mastodon. This blog post aims to summarize the steps necessary for a migration, and includes pointers to websites which can help with said move.


Icinga Director and disk checks for fuse mountpoints

When I rolled out my new Icinga2 installation, and added disk checks for all laptops, I ran into a small problem: there is a fuse mountpoint for logged in users which only the user can read. Apparently it has something to do with Flatpack.


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.


Avoid linebreaks in Hugo shortcodes

Shortcodes in Hugo are a neat and poweful system to avoid repating the same piece of text over and over again. Let’s say I have the following text:


Blog website crawlers and bots in Apache2

Found a couple more bots crawling my website, and from the look at online resources it seems I catched a few of the bad guys. Crawlers which ignore the robots.txt standard, and just crawl a website for content.

Decided to do something against it, and added a filter in Apache2.


Monitor website status with Huginn

After setting up Huginn, and implementing the actions on my todo list, I had a look at the available agents and started thinking what else they can be useful for.

One of the ideas I came up with is monitoring if a website is available, or has some trouble. I already have a monitoring system in place, but it’s a nice exercise to learn more about the other agents.


Huginn: Filter Retweets

A while ago I started using Huginn, as a replacement for IFTTT. That’s going quite well. Huginn offers more features, integrations, and especially your chains (scenarios) can be as complex as you wish. IFTTT is quite limited in this area.

I use the Twitter integration to find certain Tweets. Now this does not only find native Tweets, but also finds every Retweet made for a native Tweet. Obviously I am not interested in duplicate content.

Huginn offers a way to filter out Retweets.


Public previews in Hugo

Hugo is a static templating system. It is (mainly) used to deploy websites/blogs which don’t have and need dynamic content. The content of all pages is pre-generated, and the webserver delivers files from disk (or rather from cache, once files are loaded into memory). This approach allows for extremely fast websites, as no dynamic content is generated on every request.

While I know Hugo from work, I haven’t really used it for private projects - until recently. I have started a new project where I present interviews with people behind the PostgreSQL Project - and this is perfect for a static website. Interviews don’t change, once published.


Pushover app on Huawei Android phones

While diving deeper into my openHAB installation, the need for notifications on mobile phones came up. After some research, I settled with Pushover, which provides Android and iOS apps, as well as Desktop notifications. openHAB Rules have support for Pushover, and everything works well together.

Except when Android decides to kill apps, because they sit idle and do nothing. It so happens on my Huawei phone that notifications are delivered to the device, but no popup shows up. Only when I open the up, suddenly all the messages are there. The Pushover FAQ has an entry for this, even for Huawei phones, but it is outdated.

After another research it turns out, that the battery management in Android is at fault - but it can be disabled.