Linux Classroom notes 28/July/2026

System monitoring

• cpu
• memory
• storage
• logs
• GPU

cpu & memory

top – live cpu/memory usage per process htop – improve interactive version of top free -h ==> shows the memory free space

storage or Disk

• df -h – overal free space and details
• du -sh ~/ – specific path size use disk
• du –max-depth=1 ==> show indetail size sub dir

logs: log having information of you service or application

• less /var/log/auth.log page though auth log
• tail -f /var/log/syslog follow logs to monitor

Networking Basics:

• ip & interfaces:
  • ip addr show this will show your network ip
  • Install net tools: sudo apt install net-tools
  • ifconfig -a
• connectivity commands

  • ping -c 4 google.com check your system connect to internet

  • netstart : Common Command Flags | Flag | Description | | :— | :— | | -a | Displays all active connections and listening ports. | | -t | Filters output to show TCP connections only. | | -u | Filters output to show UDP connections only. | | -l | Filters output to show Listening sockets only. | | -n | Displays numeric IP addresses and port numbers (skips DNS resolution). | | -p | Displays the PID and process name (requires sudo). | | -r | Displays the kernel routing table. | | -i | Displays interface statistics. |

  • Install sudo apt install traceroute && excute traceroute google.com

  • sudo apt install inetutils-traceroute