I have followed Jay LaCroix and Learn Linux TV on youtube and his
website for many years learning many of the things I share with the MLUG
group.
The YouTube video listed below contains many of the troubleshooting tips
I have learned over the years in one a 24 minute video.
https://www.youtube.com/watch?v=xsdFNpThetE
Have Fun,
Roger M. Jenson