Artikel in Kategorie "Administration"

Rejecting Microsoft Executables and Office Documents with Postfix

Update July 16th 2020: A reader has pointed out to me that the regular expression did not (or did not always) match if the filename of the attachment contained non-ASCII characters, opening a simple way to circumvent this header check. I was able to reproduce this behavior by sending a mail with a single attachment […]

Sicherung von MySQL mit Disk-Snapshots

Problem Beim Backup von MySQL-Servern mit VMWare Data Protection, Veeam und mit Snapshots im Allgemeinen ist zu beachten: Ein Backup-Snapshot eines laufenden MySQL-Servers enthält nicht den Inhalt des RAMs. /var/lib/mysql im Snapshot stimmt nicht mehr mit dem RAM überein und ist möglicherweise korrumpiert. Schlussfolgerung: Dieser Snapshot ist als Backup unbrauchbar. Das Problem ist nicht VMWare-spezifisch […]

Centralized Syslog Using MongoDB And PHP

Introduction This setup codenamed „PMS“ (for PHP/MongoDB/Syslog) can be used to let one or more Syslog-servers write log messages to a MongoDB collection. They can then be accessed using a PHP web application. It has been tested on Linux using RSyslog, MongoDB, Apache and PHP (with MongoDB extension) from Devuan (Ceres). The quality of this […]

Basic Example for Response-Policy-Zones with BIND

I would like to emulate a public DNS entry that does not exist yet, while i am developing the service that will use this name on an intranet server. Let a public domain name i develop the service for be myservice.my-cool-domain.biz. When working in my intranet 192.168.2.0/24, i want to override whatever public DNS resolves […]

Providing XDG Runtime Directories

Introduction The intended audience for this document are application programmers and providers of init-systems for managing features of installations of the GNU/Linux operating system and POSIX-compliant operating systems in general, who are concerned with per-user temporary file management based on the XDG Base Directory Specification, [XDG]. Many applications that follow XDG guidelines and specifications expect […]

„nodm“: Improved „restart“ behavior

I currently maintain an experimental spin-off of the „nodm“ minimal display manager written by Mr. Enrico Zini: Spin-Off project site: https://git.devuan.org/tilt/nodm As has been reported, in recent installations of „nodm“ from Debian packages up to version 0.11.1-3 (Debian unstable), the „restart“ action of the sysvinit-script does not reliably restart „nodm“. This is due to the […]

Ad-Blocking with BIND9 and NGINX

In my intranet, where hosts are in a subnet 192.168.2.0/24 and domain names in a domain mydomain, I use BIND9 as DNS, running on host intradns.mydomain , and NGINX as a webserver running on intraweb.mydomain. I would like to rewrite all subdomains of certain public domains (spammers and trackers) using my intranet DNS to a […]

A Linux Desktop With Devuan GNU/Linux

Overview I have now installed Devuan GNU/Linux, release „stable“ (which still is alpha) on an amd64 workstation. On Devuan in general, see also my earlier statement.