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Enable Deep Sleep mode on Tuxedo Computers Pulse 15 Gen2

A while ago we bought new Pulse 15 laptops from Tuxedo Computers.

Installed Ubuntu on them, and for a while the sleep mode was nagging me, it does not really work. Today I found time to investigate this issue.


fwupdmgr: /usr/libexec/fwupd/efi/fwupdx64.efi and /usr/libexec/fwupd/efi/fwupdx64.efi.signed cannot be found

From time to time our laptops receive firmware updates, by using the Linux Vendor Firmware Service (short: fwupd). This worked fine for a long time, until it didn’t. One day I was facing the following error message:


Install Firefox PPA version over Snap version

It was time to update my laptop, and I already knew that the update will bring Snap, and installs the Snap Firefox version. Along with many known problems. Previously the laptop was on 20.04 LTS, but this version is about to loose support.

I ran through the upgrade, and then added an Ansible Playbook to handle the Firefox installation, remove the Snap version and install the PPA version. Most of my laptop configuration is handled using Ansible Playbooks.


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.


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.


Connect a Mac to a SMB server - as Guest

One of the things I do in our network is public drives. Every Linux system has a public incoming which is mapped to the primary user of the device (if there is one, like for a laptop). And this incoming shared drive can be accessed without password.

This makes it really convenient to copy files around from one laptop/user to another, or from mobile devices to laptops and vice versa, or use the printer/scanner to send the scan job directly to the laptop of the user’s device. All in all, the users like this, and use it a lot. There is also minimal protection built-in, it will only work in our home network, access is blocked when the laptop is connected to a different network. But the folders are mostly empty anyway. For sharing files over the Internet we also have a Syncthing instance running, but that’s a different story, and not as easy to use.

One thing which I was annoyed about is that by default a Mac will try to connect as a registered user. There is an option Connect as Guest, but it’s not pre-selected. Therefore every time I wanted to share something between Linux and Mac, I had to start Finder, to to Go and then Connect to Server, then click on the server from the list of last entries, and then also click on Guest. The built-in help is also not useful, as it only talks about “click on Guest”.


Huginn: Monitor changes in websites

The Huginn software is not only good for monitoring Twitter feeds, it can also be used to monitor websites for changes.


Add a Google Calendar to openHAB

openHAB can integrate Google Calendars. The functionality is kind of limited, it can only see the current and the next calendar event, but in my case that is enough. More about the use case in another blog post.


git pre-commit Hooks

A very common use case for hooks in git is a pre-commit hook. This hook is used to verify the to-be-committed data before it is added to the repository.


openHAB: faster loading of rules files

openHAB rules files are lazy loaded. When a rule is used the first time, the entire rule file is loaded and compiled, which apparently is single-threaded and takes a couple seconds. Even on a reasonable powerful Rasperry Pi 4. This happens both after restarting openHAB and after changing the rules file. It also means that whatever the rule in question is supposed to do has to wait a couple seconds when requested for the first time. Imagine you have a light switch, enter a room, press the switch, and it takes 5-10 seconds until the light comes on.

To work around this problem, I add a piece of code in all rules files which triggers an immediate action right after loading the file. This way the rules file is already pre-loaded (which again takes a couple seconds, but likely at a time when the rule is not needed right now).