Write Unix shell script to automate the backup and rotation of application log files stored in a specific directory

Create daily backups of log files.
Compress older backups.
Maintain a defined number of backup copies.
Manage disk space efficiently.

#!/bin/bash

# Configuration
LOG_DIR="/path/to/log_directory"
BACKUP_DIR="/path/to/backup_directory"
RETENTION_DAYS=7
DATE=$(date +'%Y-%m-%d')

# Ensure backup directory exists
mkdir -p "$BACKUP_DIR"

# Create a daily backup
backup_logs() {
    local backup_file="$BACKUP_DIR/logs_$DATE.tar.gz"
    tar -czf "$backup_file" -C "$LOG_DIR" .
    if [ $? -eq 0 ]; then
        echo "$(date +'%Y-%m-%d %H:%M:%S'): Successfully created backup $backup_file"
    else
        echo "$(date +'%Y-%m-%d %H:%M:%S'): Failed to create backup $backup_file" >&2
        exit 1
    fi
}

# Remove backups older than RETENTION_DAYS
cleanup_old_backups() {
    find "$BACKUP_DIR" -type f -name "*.tar.gz" -mtime +$RETENTION_DAYS -exec rm {} \;
    if [ $? -eq 0 ]; then
        echo "$(date +'%Y-%m-%d %H:%M:%S'): Successfully cleaned up old backups"
    else
        echo "$(date +'%Y-%m-%d %H:%M:%S'): Failed to clean up old backups" >&2
    fi
}

# Main script execution
backup_logs
cleanup_old_backups

Option-2

#!/bin/bash

# Define variables
LOG_DIR="/var/log/myapp"  # Directory containing application logs
BACKUP_DIR="/var/log/myapp_backups"  # Directory for storing backups
MAX_BACKUPS=7  # Maximum number of backup files to keep
LOG_FILE="application.log"  # Specific log file to backup (optional)

# Ensure backup directory exists
if [[ ! -d "$BACKUP_DIR" ]]; then
  mkdir -p "$BACKUP_DIR"
fi

# Get current date in YYYY-MM-DD format
TODAY=$(date +%Y-%m-%d)

# Create a compressed archive of the log file(s)
if [[ -n "$LOG_FILE" ]]; then
  # Backup specific log file
  tar -czf "$BACKUP_DIR/$TODAY-$LOG_FILE.tar.gz" "$LOG_DIR/$LOG_FILE"
else
  # Backup all log files in the directory
  tar -czf "$BACKUP_DIR/$TODAY.tar.gz" "$LOG_DIR/*"
fi

# Clean up old backups
count=$(ls -tr "$BACKUP_DIR" | wc -l)
if [[ $count -gt $MAX_BACKUPS ]]; then
  # Delete oldest backups until reaching the desired number
  for file in $(ls -t "$BACKUP_DIR" | tail -n +$(($count - $MAX_BACKUPS))); do
    rm -f "$BACKUP_DIR/$file"
  done
fi

echo "Log backup completed on $(date)"