Forem: Levis Chiri

🧠 Raspberry Pi Headless Setup Guide (SSH, VNC, Essentials)

Levis Chiri — Wed, 12 Mar 2025 12:13:56 +0000

This guide walks you through setting up a Raspberry Pi (headlessly) using Raspberry Pi Imager, enabling SSH, configuring Wi-Fi, setting up VNC Viewer, fixing common issues, and using essential commands.

📥 1. Installing Raspberry Pi OS Using Raspberry Pi Imager

✅ Step 1: Download Raspberry Pi Imager

Download from the official site.
Install and launch it.

✅ Step 2: Flash the OS to the MicroSD Card

Insert a microSD card (≥16GB).
Open Raspberry Pi Imager and select:

Choose OS → Raspberry Pi OS (Recommended)
Choose Storage → Select your SD card

⚙️ Configure Wi-Fi and SSH (Optional but recommended)

Click the ⚙️ (Settings) icon:

Set:
- Hostname
- Wi-Fi SSID & Password
- Enable SSH
Save & click Write to flash.

🛠️ Step 3: Manual Headless SSH & Wi-Fi Setup (If Not Done Above)

Open the boot partition on the SD card.
Create empty ssh file:

touch /boot/ssh

Create wpa_supplicant.conf:

nano /boot/wpa_supplicant.conf

Paste:

country=US
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
  ssid="Your_WiFi_Name"
  psk="Your_WiFi_Password"
  key_mgmt=WPA-PSK
}

Save & eject. Insert into Pi and power on.

💻 2. Connect to Raspberry Pi via SSH

🔍 Find the IP Address

With monitor:

hostname -I

Headless:

ping raspberrypi.local

🔐 SSH from PC

ssh pi@<Raspberry_Pi_IP>
# Example:
ssh pi@192.168.1.100

Default user: pi
Password: raspberry

🔄 3. Update the Raspberry Pi

sudo apt update && sudo apt upgrade -y

🖥️ 4. Enable & Configure VNC

Enable VNC Server:

sudo raspi-config

Go to Interfacing Options → VNC → Enable

Exit & reboot:

sudo reboot

Install VNC Server (if needed)

sudo apt install realvnc-vnc-server realvnc-vnc-viewer -y

Start:

vncserver

🔗 5. Connect via VNC Viewer

Download: VNC Viewer
Enter your Raspberry Pi IP (e.g. 192.168.1.100)

🧯 6. Fix: “Cannot currently show the desktop”

Fix 1: Set a Virtual Display

sudo nano /boot/config.txt

Uncomment or add:

hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=82

Then:

sudo reboot

Fix 2: Restart VNC

sudo systemctl restart vncserver-x11-serviced
# or
vncserver

Fix 3: Reinstall Desktop

sudo apt install --reinstall raspberrypi-ui-mods
sudo reboot

🛠️ 7. Essential Raspberry Pi Commands

🔄 System Update

sudo apt update && sudo apt upgrade -y

🔍 System Info

uname -a               # Kernel
vcgencmd measure_temp  # CPU Temp
df -h                  # Disk
free -m                # RAM

⚙️ Services

sudo systemctl status vncserver-x11-serviced
sudo systemctl restart vncserver-x11-serviced

🌐 Networking

ip a
ping google.com

📁 File Ops

ls
cd /path/to/folder
mkdir new_folder
rm -r folder_name

🔁 Reboot/Shutdown

sudo reboot
sudo shutdown -h now

🌐 8. Set Static IP (Optional)

sudo nano /etc/dhcpcd.conf

Add:

interface wlan0
static ip_address=192.168.1.150/24
static routers=192.168.1.1
static domain_name_servers=8.8.8.8 8.8.4.4

Save and reboot.

📦 9. Install Useful Software

sudo apt install python3 python3-pip git nodejs npm -y

⚡ 10. Enable GPIO for Projects

sudo raspi-config

Go to Interfacing Options → Enable GPIO

Install libraries:

sudo apt install python3-gpiozero python3-rpi.gpio -y

Test:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
print("GPIO Ready!")

🌍 11. Optional: Web Server Setup (Apache)

sudo apt install apache2 -y
sudo systemctl status apache2

Access from browser:

http://<Raspberry_Pi_IP>

project files, or embed code repos.

🐧Essential Linux Commands Every Developer Should Know

Levis Chiri — Wed, 12 Mar 2025 11:49:32 +0000

Linux is one of the most powerful and widely used operating systems in the world. It forms the backbone of everything from smartphones and smart devices to web servers and supercomputers.

Popular distributions like Ubuntu, Raspbian, Kali Linux, and Debian make Linux accessible to everyone—from beginners to advanced users.

What makes Linux especially appealing is its flexibility, speed, and open-source nature. Most importantly, knowing how to use the Linux command line unlocks a whole new level of control and efficiency.

➤ 1. File and Directory Management

ls → List files and directories.
ls -l → List files with details (permissions, owner, size, date).
ls -a → Show hidden files (starting with .).
pwd → Show the current directory path.
cd <directory> → Change to a specific directory.
cd .. → Move up one directory level.
cd / → Go to the root directory.
cd ~ → Go to the home directory.
mkdir <directory> → Create a new directory.
rmdir <directory> → Remove an empty directory.
rm <file> → Delete a file.
rm -r <directory> → Delete a directory and its contents.
cp <source> <destination> → Copy a file or directory.
mv <source> <destination> → Move or rename a file/directory.

➤ 2. Viewing and Editing Files

cat <file> → Display file contents.
less <file> → View a file with scrolling (q to exit).
head <file> → Show the first 10 lines of a file.
tail <file> → Show the last 10 lines of a file.
tail -f <file> → Continuously display the last lines of a file (useful for logs).
nano <file> → Open file in the Nano text editor.
vim <file> → Open file in the Vim text editor.

➤ 3. File Permissions and Ownership

ls -l → Show file permissions.
chmod 755 <file> → Set file permissions (755 = owner can edit, others can only read/execute).
chmod u+x <file> → Give execute permission to the owner.
chown user:group <file> → Change file owner and group.

➤ 4. Process Management

ps aux → Show all running processes.
top → Display system resource usage (press q to exit).
htop → Advanced process viewer (needs installation).
kill <PID> → Stop a process by its Process ID.
kill -9 <PID> → Forcefully stop a process.
pkill <name> → Stop a process by name.

➤ 5. Networking Commands

ifconfig → Show network interfaces.
ip a → Show IP addresses (alternative to ifconfig).
ping <host> → Test network connectivity to a host.
nslookup <domain> → Get DNS info of a domain.
wget <URL> → Download a file from the internet.
curl <URL> → Fetch data from a URL (useful for APIs).

➤ 6. Disk Usage and Monitoring

df -h → Show available disk space.
du -sh <directory> → Show size of a directory.
free -h → Display memory (RAM) usage.

➤ 7. Searching for Files and Text

find /path -name "filename" → Search for a file by name.
grep "text" <file> → Search for text inside a file.
grep -r "text" <directory> → Search for text in all files in a directory.
locate <filename> → Find a file by name (needs updatedb first).

➤ 8. Archiving and Compression

tar -cvf archive.tar <files> → Create a tar archive.
tar -xvf archive.tar → Extract a tar archive.
tar -czvf archive.tar.gz <files> → Create a compressed tar archive.
tar -xzvf archive.tar.gz → Extract a compressed tar archive.
zip -r archive.zip <files> → Create a zip archive.
unzip archive.zip → Extract a zip archive.

➤ 9. System Logs and Info

dmesg → Show system boot logs.
journalctl -xe → View system logs.
uptime → Show system uptime.
uname -a → Show system and kernel details.

Using git and git hub

Levis Chiri — Wed, 12 Mar 2025 11:27:33 +0000

Installing and Using Git

🖥️ Windows

Go to git-scm.com and download Git for your operating system.

Run the installer and follow the setup wizard (default settings are fine).

🍎 macOS

Install Git using Homebrew:

brew install git

🐧 Linux (Debian/Ubuntu)

Update and install Git using APT:

sudo apt update
sudo apt install git

✅ Verify Git Installation

Check if Git is installed by running:

git --version

Setting Up Git

Configure your username and email:

git config --global user.name "Your Name"
git config --global user.email "your.email@example.com"

Check your configuration:

git config --list

Set your default branch name to main:

git config --global init.defaultBranch main

1. Initializing a Repository

Before using Git, you need to initialize or clone a repository.

🔹 Create a new Git repository:

git init

🔹 Clone an existing repository:

git clone <repo_URL>

💾 2. Committing

🔍 Check current status:

git status

📥 Clone code from GitHub:

git clone <repo_URL>

🔹 Stage all changes:

git add .

📝 Commit with a message:

git commit -m "your message here"

🔹 Push changes to remote:

git push

🔗 Add remote repository:

git remote add origin <repo_URL>

⬆️ Push to remote for the first time:

git push -u origin master

🔍 Verify remote URL:

git remote -v

❌ Remove a remote:

git remote remove origin

3. Branching and Merging

🔍 List all branches:

git branch

🔹Create a new branch:

git branch <branch-name>

🔀 Switch to a branch:

git checkout <branch-name>

🔹Create and switch to new branch:

git checkout -b <branch-name>

🔗 Merge a branch into current:

git merge <branch-name>

🗑️ Delete a merged branch:

git branch -d <branch-name>

🔹🗑️ Force delete a branch:

git branch -D <branch-name>

📦 4. Stashing Changes

🧳 Save current changes:

git stash

📚 View stash list:

git stash list

🔹Apply and remove the latest stash:

git stash pop

🔁 Apply the latest stash (keep it):

git stash apply

🗑️ Delete the most recent stash:

git stash drop

🧹 Clear all stashes:

git stash clear

🔄 5. Pushing and Pulling from GitHub

🔗 Add remote origin:

git remote add origin <repo_URL>

⬆️ Push a branch:

git push origin <branch-name>

🔁 Push and set upstream:

git push -u origin <branch-name>

⬇️ Pull changes:

git pull origin <branch-name>

📥 Fetch changes without merging:

git fetch

📡 Fetch all remotes:

git fetch --all

🧼 6. Undoing Changes

🚫 Unstage a file:

git reset <file>

🔙 Undo last commit but keep changes:

git reset --soft HEAD~1

🔹Undo last commit and changes:

git reset --hard HEAD~1

↩️ Revert a specific commit:

git revert <commit-hash>

🧽 Discard local changes to a file:

git checkout -- <file>

📜 7. Viewing History and Logs

📖 View commit log:

git log

🧱 Condensed graph view:

git log --oneline --graph --all

🧩 Show changes in last 2 commits:

git log -p -2

📚 View reference log:

git reflog

🔖 8. Working with Tags

List all tags:

git tag

Create a lightweight tag:

git tag <tag-name>

📝 Create an annotated tag:

git tag -a <tag-name> -m "Message"

🔹 Push all tags to GitHub:

git push origin --tags

🔄 Checkout a tag:

git checkout <tag-name>

🤝 9. Collaborating In GitHub

🔍 View remote repositories:

git remote -v

➕ Add a new remote:

git remote add origin <repo_URL>

🔄 Rebase with latest changes:

git pull --rebase origin main

⬆️ Push current branch:

git push origin <branch-name>

🍴 10. Fork and Pull Request

🍽️ Clone a forked repo:

git clone <forked_repo_URL>

🔹Create a feature branch:

git checkout -b <feature-branch>

⬆️ Push your branch:

git push origin <feature-branch>

📬 Open a Pull Request on GitHub.

🧩 11. Submodules

🧱 Add a submodule:

git submodule add <repo_URL> <path>

🔄 Initialize and update submodules:

git submodule update --init --recursive

🛠️ 12. Fixing Mistakes

🍒 Apply a specific commit from another branch:

git cherry-pick <commit_hash>

✍️ Interactively edit last 3 commits:

git rebase -i HEAD~3

💥 Reset local branch to match remote:

git reset --hard origin/main

🗑️ 13. Deleting a Repository (Caution!)

⚠️ Deletes the Git history in current folder:

rm -rf .git

Setting Up SSH for GitHub

Generate an SSH key:

ssh-keygen -t ed25519 -C "your.email@example.com"

Start the SSH agent:

eval "$(ssh-agent -s)"

Add the key to SSH agent:

ssh-add ~/.ssh/id_ed25519

Copy the SSH key:

cat ~/.ssh/id_ed25519.pub

Go to GitHub -> Settings -> SSH and GPG keys -> Add a new key -> Paste the copied key.

Test the connection:

ssh -T git@github.com

Set Git to use SSH:

git remote set-url origin git@github.com:username/repository.git