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By default Linux distros ship with a internal MTA. If you send local mails they land in /var/mail/<user>. If you want to send external mails you have to configure your MTA to use a relay server. Exim was the default for quite some time but has been replaced with postfix since in many distros. InstallRead more
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Maybe you are limited and have no SFTP client available or just want a simple fast way to copy some config files from a server. All the tools you need are already installed. To backup the current directory It returns your files compressed and encoded as base64 with owner mappings and file permissions. You canRead more
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APT is a great package manager and there are several options to make upgrades more comfortable. Let me introduce you some. APT Configuration There are several configuration options for apt using /etc/apt/apt.conf.d/ In my case I enabled the periodic update schedule which will automatically update the package list, download upgrades but does not install them andRead more
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Instead of using the GUI you can simply use a SFTP client like Filezilla. This way you can download and upload any files. To do so open Filezilla and enter “sftp://server-ip” into the “Host” field. Then enter “Username” and “Password” and leave “Port” empty. If you use private key authentication add your key to FilezillaRead more
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Note: This is for a single host setup if you want to share the ups see https://herold.space/share-ups-using-nut-on-a-raspberry-pi UPS Setup Install the apcupsd daemon and configure it. UPS Calibration Lead-acid batteries lose capacity over time and after 3 to 5 years they need to be replaced. Therefore it’s important to calibrate them once a year. BeforeRead more
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Plex, Emby and Jellyfin can transcode media files on the fly so you can watch them in a browser and set the quality. However by default they use the CPU which adds a lot of overhead. All Intel CPU’s since Sandy Bridge released in 2011 have hardware acceleration for H.264 built in. So if yourRead more
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Overview of some services on my network. The setup is fully redundant as high availability cluster. Driven by open source and powered with renewable energy. Using Terraform, Cloud-init and Ansible for IaC. And K8s, Gitlab, Flux2 and Renovate for GitOps. Network Diagram DMZ Service Description Postfix, Dovecot, SpamAssassin Email Server with DKIM, DMARC, SPF, DANE,Read more
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Welcome on herold.space My name is Constantin Herold I’m a software engineer and this is my blog where I document some sysadmin, devops and dev stuff. Most posts are kept private ¯\_(ツ)_/¯ feel free to browse my docsRead more