Linux sysadmin training

[ChillswitchEngage]

I am trying to familiarize myself with RHEL and linux in general for enterprise IT support and am trying to give myself little projects to try within virtualbox for it. Like for instance, I made a simple shared folder with samba in RHEL to share to another macOS and Win11 VMs I have setup. Today, I am going to try and setup a virtual network printer that can be used by all three machines. Anything else like that I could try?

[OpusX]

tmux, mc, htop, iftop, netcat, sed, awk, grep.....so many more

[ChillswitchEngage]

Yeah, I've been trying to get a handle on the terminal and common/useful commands using the Linux Journey website as I go along. I have a short attention span though so I feel like I learn better with actual scenarios so to speak.

[Shaftski]

users and usergroups. learn how to manage system/application/file access for both
master the chmod command for locking down file permissions
learn shell scripting and perl. use them to automate simple system tasks
once your scripting is solid, learn to use them as crontabs for automated scheduled system maintenance

it's a deep dive but if you start out being solid on the basics the rest becomes easier

[Criticalhammer]

Depends on what you're trying to accomplish. Off the top of my head things you should know...

File permissions (including sticky bit)
Using cron
Networking at the command line
Grep, Awk, Print, Sed, Cut, CHmod, CHown, Ps, Netcat, Netstat, Wget, Ntop, Htop, Pgrep, Cat, Head, Tail, Lsof, Curl, Kill (and its levels)
STDIN, STDOUT, STDERR
Everything there is to know about rsync
Everything there is to know about SSH
Everything there is about BASH shell (and its scripting component)
Compiling code from source
Answer the question "why does the 'root' account have the capabilities it has" or "What gives 'root' account its capabilities"
Automating package management
Kernel space, User space, Ring levels.

Thats just off the top of my head. Once you know that stuff, you should have a understanding on how Linux interfaces with hardware, how to automate stuff, how to secure stuff, and how to install/remove stuff

EDIT: With Linux virtualization comes cgroups, and namespaces.

[Siress]

I just piddle around for some home servers, but having to re-learn a bunch of stuff after implementing security enhanced linux (SEL) was awful... Might be worth starting out with SEL first.

Oh, and no one mentioned GIT command line. Use it for everything.

On the advanced side, I enjoy reading about 'infrastructure as code' but am not there yet myself.

[RAZRBAKK]

If you're not familiar with Linux specifically, I would recommend the ProLUG Linux Labs:

https://killercoda.com/het-tanis/course/Linux-Labs

It's not RHEL specific, but I got a ton out of it. I've been a Linux Desktop user for over 15 years, but never delved into servers or enterprise until recently.

[ChillswitchEngage]

These kinds of interactive sites/labs are exactly what I am after, thank you so much! I found a section on jr sys admin for linux which is just perfect for me.

https://killercoda.com/fishermanguybro

[gnarlynick]

A lot of my Linux knowledge came from on the job training. I try to approach it with a specific use-case, like "I need to review logs for a service to identify when a fault occurred." From there, I learn how to make that actionable. It naturally snowballs from there and you get to piece everything you learn together into actual full-fledged sysadmin tasks.

I did a few online Linux courses as well, but those tend to repeat themselves and you wind up in a cycle of just reiterating over the basics.