My experience is I did a systems administration internship and i had to play with all the services, it taught me a ton about tools and layers below where I usua

My experience is I did a systems administration internship and i had to play with all the services, it taught me a ton about tools and layers below where I usually operate (Go APIs and backend services). If you're just wanting to get skills on system administration and linux. I'd start with either 1) an old machine you have lying around (or pluck one from a recycling center) or 2) a virtual machine, and 3) once you have confidence on a single box, start to use multiple to make clusters/replica sets of things like multiple nodes of HTTP server, or multiple nodes of a mongodb, etcd or other distributed systems. Try doing work on them and pulling the plug on one mid execution to see what happens. From there try to play with a bunch of the following things: (OTOH, no particular order) setup a domain name server like bind (<something>.localhost?), setting up an SMTP service, setup an IMAP/POP3 service, set up a http server like nginx, lighttp, apache, try communicating to the http service over telnet, setup a https certificate with lets encrypt, try doing the same telnet to https and get it piped through gnutls, setup nightly backups to an external HD (try rsync), setup a spam filter for your SMTP server, try to run excalidraw on your http service, build an api that sits behind your HTTP(s). use tcpdump and wireshark to inspect network traffic. Most of that should be google-able :) Edit: MOAR fail2ban, ssh-server, iptables firewall, irc server, sftp host, kubernetes cluster of virtual machines, hadoop/spark for a map reduce workload, check out https://www.cncf.io/projects/ https://www.cncf.io/projects/ and start to learn to build with those projects/abstractions.