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🐧 How to Create a Linux Swap File
Create, activate, and manage swap space on a Linux server using a simple, interactive Bash script.
🛠️ Option 1: Quick Setup with create-swap.sh
📝 Save the Script
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Create the script file:
nano create-swap.sh -
Paste this script inside:
#!/bin/bash # Prompt the user for swap size read -p "Enter swap size in MB (e.g., 1024 for 1GB): " SWAP_SIZE_MB # Validate input if ! [[ "$SWAP_SIZE_MB" =~ ^[0-9]+$ ]]; then echo "❌ Error: Please enter a valid numeric value." exit 1 fi SWAP_FILE="/swapfile" echo "🛠️ Creating a ${SWAP_SIZE_MB}MB swap file at ${SWAP_FILE}..." # Create the swap file if ! sudo fallocate -l ${SWAP_SIZE_MB}M ${SWAP_FILE}; then echo "⚠️ fallocate failed, falling back to dd..." sudo dd if=/dev/zero of=${SWAP_FILE} bs=1M count=${SWAP_SIZE_MB} status=progress fi # Set the correct permissions sudo chmod 600 ${SWAP_FILE} # Format the file as swap sudo mkswap ${SWAP_FILE} # Enable the swap file sudo swapon ${SWAP_FILE} # Make the swap persistent if ! grep -q "${SWAP_FILE}" /etc/fstab; then echo "${SWAP_FILE} none swap sw 0 0" | sudo tee -a /etc/fstab > /dev/null fi echo "✅ Swap setup completed!" swapon --show free -h
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Run the script:
chmod +x create-swap.sh && ./create-swap.sh
🛠️ Option 2: Manual Swap File Creation
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Create a 1GB swap file (change the size as needed):
sudo fallocate -l 1G /swapfileOR use
ddas a fallback (only if the first command is not working):sudo dd if=/dev/zero of=/swapfile bs=1M count=1024 status=progress -
Secure the file:
sudo chmod 600 /swapfile -
Set it up as swap:
sudo mkswap /swapfile -
Enable the swap:
sudo swapon /swapfile -
Make it permanent:
echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab -
Confirm it’s active:
swapon --show free -h
WARNINGTo Remove the Swap File:
sudo swapoff /swapfile && rm /swapfile && sed -i '/\/swapfile/d' /etc/fstab
🐧 How to Create a Linux Swap File
https://www.itsnooblk.com/posts/create-swap/