Category: DevOps

  • Yet another cluster update

    UniFi: made a deployment and network setup. Does not see AP’s. 10001 UDP seems to be a problem, yet no idea why. Adopted them manually via SSH, now they work. Yes, consumes RAM for no reason. Why? No idea. However, the functionality is limited compared to the Windows app, and it does not provide me…

  • Cluster update

    Out of all services, only Mastodon and UniFi Network controller are left, both are technically possible, but require strange things. Own Bitwarden service works great, however, needs a license to be OTP key. The Minecraft server works great. Done log aggregation, local Docker registry, metrics to have them in Lens, backups of everything. The phone…

  • Postfix and greylisting

    Spam became a noticeable threat for the mail servers many years ago. No servers today could be running without being hardened against the spam: according to some reports up to 75% of all the email traffic is spam. It’s noticeable from network capacity, hardware and electricity consumption even if you run a small company mail…

  • Postfix mail server with DKIM

    Installation and configuration of the mail server (Mail Transfer Agent, MTA) is one of the typical tasks any system administrator faces. Here we will cover the task and by the end of the article will have CentOS 7 with Postfix mail server that listens to he 25 port (SMTP) and delivers messages for the selected…

  • Moved to Hetzner and CentOS 8

    Turns out I had lost my keys to the Oracle Cloud and the Oracle Cloud lost my PTR record somehow, so the Gmail started to junk and bounce my mail. I decided to go for a Faster.cz (who’s my home provider) VPS, but they had 8GB SSD as an option for a small host, which…

  • Puppet vs Ansible vs Chef vs Salt

    Good presentation, high level.