tune2fs Command Linux: Complete Guide to Ext2/3/4 Filesystem Tuning

tune2fs [options] device

# Display filesystem information
tune2fs -l /dev/sda1

# Set maximum mount count to 30
tune2fs -c 30 /dev/sda1

# Disable mount count checking (set to -1)
tune2fs -c -1 /dev/sda1

# Check current mount count
tune2fs -l /dev/sda1 | grep "Mount count"

Mount count:              15
Maximum mount count:      30

# Set check interval to 180 days
tune2fs -i 180d /dev/sda1

# Set check interval to 4 weeks
tune2fs -i 4w /dev/sda1

# Disable time-based checking
tune2fs -i 0 /dev/sda1

# Set reserved blocks to 2% of filesystem
tune2fs -m 2 /dev/sda1

# Reserve specific number of blocks (e.g., 1000 blocks)
tune2fs -r 1000 /dev/sda1

# Set reserved blocks for specific user (UID 1000)
tune2fs -u 1000 /dev/sda1

# Set filesystem label
tune2fs -L "MyDataDrive" /dev/sda1

# Remove filesystem label
tune2fs -L "" /dev/sda1

# View current label
tune2fs -l /dev/sda1 | grep "Filesystem volume name"

# Generate random UUID
tune2fs -U random /dev/sda1

# Set specific UUID
tune2fs -U 12345678-1234-1234-1234-123456789012 /dev/sda1

# Clear UUID
tune2fs -U clear /dev/sda1

# Set journal size (in MB)
tune2fs -J size=64 /dev/sda1

# Enable specific journal options
tune2fs -o journal_data /dev/sda1

# Set default mount options
tune2fs -o acl,user_xattr /dev/sda1

# Continue on errors
tune2fs -e continue /dev/sda1

# Remount read-only on errors
tune2fs -e remount-ro /dev/sda1

# Panic on errors
tune2fs -e panic /dev/sda1

# Configure boot partition for minimal maintenance
tune2fs -c -1 -i 0 -m 1 -L "BOOT" /dev/sda1

# Verify changes
tune2fs -l /dev/sda1 | grep -E "(Mount count|Check interval|Reserved|volume name)"

Filesystem volume name:   BOOT
Maximum mount count:      -1
Check interval:           0 ()
Reserved block count:     102

# Configure large data partition
tune2fs -c 50 -i 6m -m 2 -e remount-ro -L "DATA" /dev/sdb1

# Add extended attributes support
tune2fs -o user_xattr,acl /dev/sdb1

# Add journal to convert ext2 to ext3
tune2fs -j /dev/sdc1

# Verify journal creation
tune2fs -l /dev/sdc1 | grep "has_journal"

#!/bin/bash
# Filesystem Health Monitor

DEVICE="$1"

if [ -z "$DEVICE" ]; then
    echo "Usage: $0 /dev/devicename"
    exit 1
fi

echo "=== Filesystem Health Report for $DEVICE ==="
echo

# Basic information
echo "Filesystem Type:"
tune2fs -l "$DEVICE" | grep "Filesystem OS type"

echo -e "\nMount Information:"
tune2fs -l "$DEVICE" | grep -E "(Mount count|Maximum mount count)"

echo -e "\nCheck Information:"
tune2fs -l "$DEVICE" | grep -E "(Last checked|Check interval)"

echo -e "\nSpace Information:"
tune2fs -l "$DEVICE" | grep -E "(Block count|Reserved block count|Free blocks)"

echo -e "\nError Behavior:"
tune2fs -l "$DEVICE" | grep "Errors behavior"

# Calculate next check
MOUNT_COUNT=$(tune2fs -l "$DEVICE" | grep "Mount count:" | awk '{print $3}')
MAX_MOUNT=$(tune2fs -l "$DEVICE" | grep "Maximum mount count:" | awk '{print $4}')

if [ "$MAX_MOUNT" -gt 0 ]; then
    REMAINING=$((MAX_MOUNT - MOUNT_COUNT))
    echo -e "\nMounts until next check: $REMAINING"
fi

# Root filesystem (/)
tune2fs -c 30 -i 180d -m 5 -e remount-ro /dev/sda1

# Boot partition (/boot)
tune2fs -c -1 -i 0 -m 1 /dev/sda2

# Home partition (/home)
tune2fs -c 50 -i 6m -m 1 -o user_xattr,acl /dev/sda3

# Large data partitions
tune2fs -c -1 -i 1y -m 0.5 /dev/sdb1

# Error: tune2fs: Permission denied while trying to open /dev/sda1
# Solution: Run with sudo
sudo tune2fs -l /dev/sda1

# Error: tune2fs: Device or resource busy
# Solution: Unmount the filesystem first
umount /dev/sda1
tune2fs -c 30 /dev/sda1
mount /dev/sda1

# Weekly filesystem health check script
#!/bin/bash
for device in $(df -t ext4 | awk 'NR>1 {print $1}'); do
    echo "Checking $device..."
    tune2fs -l "$device" | grep -E "(Mount count|Last checked|Errors behavior)"
    echo "---"
done