ubuntu cli tips

notes_ubuntu-CLI.md

List of useful cli tools in ubuntu

• altinstall
• jobs
• rclone
• cron
• tmux (session continuity in remote sessions)
• mitmproxy
• cockpit (docker)
• puppet | chef | ansible | rudder ( remote server compliance )
• top | htop | ntop

ALTINSTALL (Multiple Pythons Example)

• wget https://www.python.org/ftp/python/3.7.9/Python-3.7.9.tgz
• ./configure ––enable–optimizations
• tar -xf Python-3.7.9.tgz
• cd Python-3.7.9
• sudo make altinstall
• make -j 20
• sudo make altinstall

setting python versions via Altinstall

• sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.7 1
• sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2

To CHANGE IN FUTURE

• sudo update-alternatives --config python3

CONCLUSION

• not good approach, ubuntu 20, starts getting confused.(still)

JOBS

• ctrl+z | will send current process in background
• 'jobs' | will list background jobs with numbers or PIDS
• 'fg #' | will bring that task/job back again

rclone (use gui)

• rclone rcd --rc-web-gui
• More Tips Here
• https://linuxpip.org/rclone-examples/

Setup Config via rclone config

• https://rainbowninjas.co.uk/nextcloud/remote.php/webdav
• user
• password Copy files via
• rclone -v copy src dest:/

CRON

• good stuff here
  • https://phoenixnap.com/kb/set-up-cron-job-linux
• crontab -e
• sudo service cron reload

CREATING SERVICE / DAEMON

• sudo nano /etc/systemd/system/time-laspe.service

  Enable Above service

  • sudo systemctl enable time-lapse.service

[Unit]

Description=time lapse

After=multi-user.target

[Service]

Type=simple

ExecStart=/home/pi/time-lapse.sh

User=pi

WorkingDirectory=/home/pi

Restart=on-failure

[Install]

WantedBy=multi-user.target

FINDING A SERVICE / PROCESS

• top -p $(pgrep -d',' httpd)

COPY SERVER LOG TO LOCAL MACHINE (if needed)

pscp -sftp -P 7822 -pw password user@ip:/home/logs/topLog.txt C:\Users\me\Desktop\topLog.txt

TOP

• top >> h ?
• top -b -n1 > logs/topLog.txt (run in batch move | outputs data - in log file)
• top -o %CPU -d 10 -i (sort cpu usage wise | refresh after 10 - seconds | hide idle processes)
• top -u root (show root user processes)

SHORTCUT KEYS

• q > quit
• ctl+z > hide
• fg > show again
• a > toggle standard / alterV
• j > align numbers to right
• r > reverse sort (high to low)
• i > hide idle tasks
• m > messages
• shift + m >
• Z > color
• s > summary
• t > tasks
• 1-9 colors
• b > bold text
• pgup | pgdn scroll

FLAGS

• -h show current version
• -d specify delay time refresh
• -o sort by name field
• -p show process by id
• -u show process by user
• -i do not show idle task