Delayed processing in RabbitMQ with Dead Letter Exchanges In 2014 we were in the process of migrating from our Rails monolith to a service oriented architecture (or microservices). For Rails we had utilized DelayedJob in order to schedule code to be
linux Linux Mint 20 Upgrade on Lenovo Thinkpad X1 Carbon 7th Sound and Fingerprints Linux Mint 20 has been released some days ago and now there is also the upgrade guide available for you who also have Mint 19.3 running. I don't want to cover the
RabbitMQ Cluster Migration In 2014 we introduced RabbitMQ in our production system as a means of doing asynchronous/background processing in our system. We needed to replace a functionality that we were handling with DelayedJob in
2fa Automate TOTP-secured SSH logins with 2sh and Bitwarden As an additional way to protect SSH servers from potential attackers, I started to implement TOTP-based 2FA logins in the past. See this post about how I achieved this. I also use Bitwarden
linux Network Locations with multiple VLANs on Linux Mint If you've used the Network Locations feature on your Mac and are wondering how to set it up on Linux - you've come to the right place. Working as a systems administrator I
linux Setup SublimeLinter with RVM and ZSH under Linux Mint 19.3 Cinnamon In my previous posts I took you onto a journey from my old macOS environment to my new home - Linux Mint 19.3 Cinnamon. As with every journey, you have quests to
linux Setup Soundcard and Microphone on Lenovo Thinkpad X1 Carbon 7th Gen with Linux Mint 19.3 Recently I switched my work device from my very old MacBook Pro Mid-2012 Non-Retina to a brand new Lenovo Thinkpad X1 Carbon 7th Gen - or X1C7 for short - with Linux Mint
linux Enabling U2F Hardware token in Linux I recently switched from MacOS to Linux for my work computer and found out that using a hardware U2F USB token is not so easy as on MacOS. I'm using a Yubikey and
dell Online capacity expansion of a Dell Hardware RAID 1 with larger disks and a LVM This post is about a simple topic, but finding information about it was not so easy due to the specific circumstances it includes. Here i will show you how you can accomplish the
Improve the battery life of your notebook running Linux OS Running Linux on your notebook and wondering about poor battery life? In this article I'll give you some hints how to increase the lifetime of your battery. No magic here, but still may
proxmox Proxmox / Linux - Live-Update Network Configuration with Zero-Downtime In this smaller post i want to show you how easy it is to do a live config update of your network without network restarts or machine reboots. I did this just recently
Calculating EAN Check Digits in Postgres with SQL Imagine you have EAN codes in the database. The values either do not have the corresponding check digit or you want to verify that the number you have stored is correct. You do
Remove Proxmox 5.3 “No Valid Subscription” message IntroductionIn 2016, i already wrote a post about removing this message from older Proxmox 4.2 and newer, with the help of user comments. Some time has passed and i have also updated
golang Database anonymization in Golang using views A couple of years ago we faced an interesting problem: We wanted to be able to recreate the state of our production system as close as possible in a separated staging system for
cron Cronlocker - Distributing Cronjobs Across Hosts One of the goals in operating any IT system is to make it available 100% of the time. Having the best of the best of the best hardware to ensure reliability is not
debian Site-to-Site IPSec VPN between Sophos UTM and Debian using StrongSwan with RSA-Pubkeys Introduction This guide will show you, how you can establish a Site-to-Site IPSec VPN between a Sophos UTM Firewall and a Debian 9 "Stretch" based Server using StrongSwan with RSA Public-Key
debian Hetzner Root-Server with dual Hardware RAID-1 and encrypted LVM on Debian 9 Introduction This guide will explain the steps it takes to install a secure headless Hetzner Root-Server with some special pitfalls like LUKS on Hardware-RAIDs and SSH-based remote decryption at boot time for more
sophos utm Automating Pingdom Probes IP-Whitelisting with Probecollector Introduction It was hard to find a good title for this blog post, so let me explain it a bit further. You may have API's or applications that are secured with IP-Whitelisting or
debian Add Two-Factor-Authentication to SSH on Debian Wheezy to Stretch Introduction This guide shows you, how you can add 2FA to your OpenSSH on Debian Wheezy, Jessie and Stretch using Google Authenticator. We assume that your SSH already uses Pubkey-Authentication while PasswordAuthentication is
Hetzner Proxmox 5 on Hetzner Root-Server with Dual-Stack IPv4/IPv6 for Host and Guests Introduction In an earlier blog post i wrote about a standard Debian installation with KVM, IPv4 and IPv6 for both the host and it's guests. This time we will setup Proxmox 5.x
proxmox Migrating Proxmox LVM-Thin Volumes to another Proxmox Host Introduction In an earlier post, i've discribed how to migrate VMWare ESXi Virtual Machines (or mostly their disks) to a new Proxmox KVM machine. This time i had to move a Proxmox VM
proxmox Proxmox 4Gbit/s HA Networking with two Dual-Port NICs and VLAN-enabled Bonding to distinct Switches Lately we've setup a new Proxmox 4.4 Server. For this we upgraded our former ESXi 5.5 Host with more RAM, a RAID-10 Array (from RAID-1 w. Hot-Spare) and two Dual-Port 1Gbit/
vmware Migrate VMWare ESXi Virtual Machines to Proxmox KVM with LVM-Thin Logical Volumes Recently we decided to move away from VMWare ESXi because we want to scale out but don't want to buy expensive licenses just for virtualization. We evaluated different solutions and got stuck with
security Securing and Customizing Filecloud Server and Clients Update 2017-06-15: The configuration parameters below still work with the latest Sync Clients in v15.x (tested on macOS and Windows). Sadly, the default is still TLSv1 and not configurable in the UI
sophos utm Monitoring RAID on Sophos UTM Hot-Standby Clusters with Dell PERC/LSI MegaRAID Controllers This is a somewhat special post this time for a somewhat narrow audience but my intention was splitted into creating a reminder for myself and to show how you can even monitor things
