Blog | JackGruber

Low power Arduino Pro Mini

Posted on December 27, 2019

For various projects where a long runtime with batteries is important I use a modify Arduino Pro Mini 328 3.3V/8Mhz (ATmega328P). As an example a flashing sketch is used, which turns the LED on for 1 second and off for 8 seconds. [Read More]
Tags:
- howto
- hack
- Arduino
- µC
- Hardware
gnupg cannot connect to keyserver

keyserver receive failed: Connection refused

Posted on June 7, 2019

On a docker project where i had to add gnupg keys i always got an error keyserver receive failed: Connection refused. After a while of troubleshooting, i realized it’s not a connection or DNS problem. But that the Dirmngr did not use the configured DNS servers of the system. gpg... [Read More]
Tags:
Security hardware key on Github with Firefox

Spoof User Agent in Firefox

Posted on June 7, 2019

Github currently supports hardware security keys (SoloKeys, Yubico, …) as second factor only with Google Chrome but not with Firefox, although Firefox supports U2F and on other sites this also works flawlessly. This browser doesn’t support the FIDO U2F standard yet. [Read More]
Tags:
- howto
- firefox
- U2F
- SoloKeys
- security
- FIDO U2F
- 2FA
PowerShell and MQTT

Posted on June 5, 2019

A small blog entry how to use MQTT in Powershell, as a library I use M2MQTT. [Read More]
Tags:
- powershell
- code
- mqtt
- iot
Setup your own Firefox Sync Server with Docker

Posted on November 3, 2018

If you don’t want your bookmarks, tabs, cronics, … to be stored by Firefox in the Firefox cloud, you can run your self-hosted Firefox Sync server. After that, only the Mozilla-hosted accounts server (https://accounts.firefox.com) is used, but the data is stored locally. [Read More]
Tags:
- docker
- howto
- network
- cloud
- firefox
Overlapping subnetworks or how to change Docker default subnet size?

Posted on October 31, 2018

Several services already running were no longer available from subnets after a new container was created using docker-compose. The control of the IP addresses showed that a new network 192.168.X.0/20 was created, which overlapped the existing networks and therefore the communication did not work anymore. [Read More]
Tags:
- docker
- howto
- error
- troubleshooting
- network
Git Server on Synology NAS

Posted on August 25, 2018

Short HowTo to install and configure of a Git Server on a Synology NAS with DSM 6.2. [Read More]
Tags:
- git
- synology
- howto
Push a multi architecture image to Docker Hub

Posted on May 13, 2018

To create Docker images with multi architecture support, create your Docker image as usual with a tag for the architecture and push them to the Docker Hub. After all images has been pushed, create a manifest file and push them as :latest image to the Docker Hub. [Read More]
Tags:
- docker
- howto
Capture output from command line tools with PowerShell

Posted on May 11, 2018

There are several ways to execute an external process and capture and process its command output in PowerShell. [Read More]
Tags:
- powershell
- code
- process
Check group membership with PowerShell

Posted on May 10, 2018

Check group membership from the current user without Active Directory PowerShell module. [Read More]
Tags:
- powershell
- code