Q: How can you see which kernel version a system is currently running?Edit
uname prints out system information. More specifially uname -a will list all the information you would need/want to know about the system you are on.
Q: How can you check a system's current IP Address?Edit
ip addr show
Q: How do you check for free disk space?Edit
This will give you a readout of all of your file systems including virtual file systems.
Q: How do you manage services on a system?Edit
service <service name> status service <service name> start service <service name> stop
systemctl status <service name>
Q: How would you check the size of a directory's contents on disk?Edit
du -sh <directory name>
Q: How would you check for open ports on a Linux machine?Edit
sudo netstat -tulpn
Q: How do you check CPU usage for a given process?Edit
ps aux | grep <process name>
A: Mounting a new harddrive:
ls /mnt mount <absolute path to the volume> <mount point> e.g mount /dev/sda2 /mnt
Checking for existing mounts:
Q: If you need to automatically mount a volume at boot, what file would you look in?Edit
Q: How do you look up something you don't know?Edit
All hail the man/manual pages!!
Google/Stack Overflow... duh