Scott Diemer
July 31, 2026
Systems AdministrationLinux

Technical Update: Pre-Upgrade Backups, Ubuntu 24.04 LTS Migration & Service Recovery

Upgraded main VPS infrastructure from Ubuntu 22.04 to 24.04 LTS (Noble Numbat). Created manual tarball archives and MySQL dumps for Mailcow, osTicket, and Nginx configurations prior to the migration. Restored full osTicket functionality by installing PHP 8.1-FPM via the Ondřej Surý PPA to resolve PHP 8.3 incompatibilities, re-initialized Docker stacks, and updated UFW and Fail2ban whitelists.

July 29, 2026
NetworkingNotes

Notes: The Network Layer

Notes on section 'The Network Layer' on 'The Bits and Bytes of Computer Networking' course at Coursera/Grow with Google.

July 21, 2026
Systems AdministrationNetworking

Deploying and Hardening a Self-Hosted Mailcow Mail Server

Documented the deployment of a containerized Mailcow mail server (Postfix, Dovecot, Rspamd) on an Ubuntu VPS, including osTicket integration, Postfix IPv4 routing adjustments, and full DNS authentication hardening (SPF, DKIM, DMARC, and PTR) to achieve a 10/10 mail deliverability score.

July 20, 2026
Systems Administration

osTicket Deployment & Infrastructure Hardening

Deployed a production-ready osTicket instance on a dedicated subdomain (tickets.scottdiemer.com) hosted alongside a portfolio server. Documented full Nginx, MariaDB, and PHP-FPM stack setup, Let's Encrypt SSL provisioning, file permission hardening, setup directory cleanup, and database-level authentication fixes in preparation for Active Directory LDAP integration.

July 7, 2026
IT Support Certification

Learning Journal: Diving into the Architecture of Networking

An overview of the fundamental components of computer networking covered in Module 1, focusing on the TCP/IP five-layer model, physical infrastructure including twisted-pair and fiber-optic cabling, and the behavioral evolution from hubs to switches and routers.

July 6, 2026
Learning Path

Diving into Networking and Homepage UI Refinements

Started Course 2 of the Google IT Support Certificate focusing on the TCP/IP model, while pushing new terminal animations, milestone links, and navigation fixes to the homepage.

June 29, 2026
Fundamentals

Technical Review & Completing OS Fundamentals

Completed the OS Fundamentals module, passing an interactive architectural review on kernel mechanics and provisioning live Windows and Linux virtual machines via Qwiklabs.