This system automatically mirrors GitHub repositories to your local machine, preserving all branches, tags, and refs. The mirrors are kept in sync with daily automatic updates via cron.

• Mirror multiple GitHub repositories with a single command
• Preserves all branches and tags (no pruning)
• Automatic daily updates at midnight via cron
• Detailed logging of all backup operations
• Automatic log rotation (keeps last 30 days)
• Color-coded console output for easy monitoring
• Handles both initial cloning and incremental updates

opennav_repo_backups/
├── BACKUP_REPOS.TXT      # List of repositories to mirror
├── mirror_repos.sh        # Main backup script
├── setup_cron.sh          # Cron setup script
├── README.md              # This file
├── mirrors/               # Mirrored repositories (created automatically)
│   ├── ros-navigation_navigation2.git/
│   └── ros-navigation_docs.nav2.org.git/
└── logs/                  # Backup logs (created automatically)
    └── mirror_YYYYMMDD_HHMMSS.log

Edit BACKUP_REPOS.TXT and add the repositories you want to mirror (one per line):

ros-navigation/navigation2
ros-navigation/docs.nav2.org

Format: owner/repository

You can add comments by starting a line with #:

# ROS Navigation repositories
ros-navigation/navigation2
ros-navigation/docs.nav2.org

# Additional repos
another-org/another-repo

Run the cron setup script:

./setup_cron.sh

This will configure a cron job to run the backup script daily at midnight (00:00).

You can run an immediate backup without waiting for the cron schedule:

./mirror_repos.sh

To run a backup manually at any time:

./mirror_repos.sh

1. Edit BACKUP_REPOS.TXT
2. Add new repository in the format owner/repository
3. Save the file

The new repository will be included in the next scheduled backup, or you can run ./mirror_repos.sh immediately.

Logs are stored in the logs/ directory with timestamps. To view the most recent log:

ls -t logs/ | head -1 | xargs -I {} cat logs/{}

Or view all recent logs:

ls -lht logs/

To verify the cron job is installed:

crontab -l | grep mirror_repos.sh

To view cron execution logs:

# Ubuntu/Debian
grep CRON /var/log/syslog | grep mirror_repos

# Systems with systemd
journalctl -u cron | grep mirror_repos

To stop automatic backups:

crontab -e

Then delete the line containing mirror_repos.sh, save and exit.

1. The script reads all repositories from BACKUP_REPOS.TXT
2. For each repository:
   • First time: Clones the repository as a mirror using git clone --mirror
   • Subsequent runs: Updates the existing mirror using git remote update
3. No pruning: All branches and refs are preserved, even if deleted from the remote
4. Each operation is logged with timestamps

A mirror clone (git clone --mirror) creates a bare repository that includes:

• All branches
• All tags
• All refs
• All remote tracking information

This is ideal for backups as it captures the complete repository state.

Mirrors are stored in the mirrors/ directory with the naming format:

owner_repository.git

For example:

• ros-navigation/navigation2 → mirrors/ros-navigation_navigation2.git/

To create a working copy from a mirror:

git clone mirrors/ros-navigation_navigation2.git/ working-copy

To see all branches in a mirror:

cd mirrors/ros-navigation_navigation2.git/
git branch -a

To see all tags:

cd mirrors/ros-navigation_navigation2.git/
git tag -l

If you need to push a mirror to another GitHub account or Git server:

cd mirrors/ros-navigation_navigation2.git/
git push --mirror https://github.com/your-account/new-repo.git

If you get permission denied errors, make scripts executable:

chmod +x mirror_repos.sh setup_cron.sh

1. Check cron is installed and running:

   systemctl status cron

2. Verify the cron job exists:

   crontab -l

3. Check system logs for cron errors:

   grep CRON /var/log/syslog

Check the latest log file in logs/ for error messages. Common issues:

• Network connectivity problems
• Repository no longer exists or is private
• Insufficient disk space

Monitor disk usage as mirrors can grow large:

du -sh mirrors/

Edit the cron job to run at a different time:

crontab -e

Modify the schedule (format: minute hour day month weekday):

• 0 0 * * * - Midnight daily (default)
• 0 2 * * * - 2:00 AM daily
• 0 0 * * 0 - Midnight every Sunday
• 0 */6 * * * - Every 6 hours

Edit mirror_repos.sh and change the BACKUP_DIR variable:

BACKUP_DIR="/path/to/custom/backup/location"

Logs older than 30 days are automatically deleted. To change this, edit the cleanup line in mirror_repos.sh:

find "$LOG_DIR" -name "mirror_*.log" -type f -mtime +30 -delete

Change +30 to your desired number of days.

To verify a mirror is healthy:

cd mirrors/ros-navigation_navigation2.git/
git fsck --full

1. Regularly verify backups are running (check logs weekly)
2. Test restoration occasionally by cloning from mirrors
3. Monitor disk space usage
4. Keep the backup directory on a separate disk/partition for better reliability
5. Consider additional offsite backups for critical repositories

These scripts are provided as-is for backup purposes.

For issues or questions:

• Check the logs in logs/ directory
• Review the troubleshooting section above
• Ensure scripts have execute permissions
• Verify cron is running correctly