rsync - Remote Sync Tool for Termux

Last Updated: October 2025
Official Website: https://rsync.samba.org/
GitHub Repository: https://github.com/WayneD/rsync
Latest Stable Version: 3.3.0 (released April 2024)

Table of Contents

Overview

rsync is a fast, versatile file synchronization and transfer tool. It uses a delta-transfer algorithm that only sends differences between files, making it extremely efficient for:

  • Backing up files locally or remotely
  • Mirroring directories
  • Incremental backups
  • Synchronizing files between devices

Key Features (as of 2025)

  • Delta-transfer algorithm - only transfers changed portions
  • Compression - reduces network bandwidth usage
  • Preservation - maintains permissions, timestamps, ownership
  • Partial transfers - resume interrupted transfers
  • SSH integration - secure remote transfers
  • Exclude patterns - flexible file filtering

Installation in Termux

# Update package list
pkg update

# Install rsync
pkg install rsync

# Verify installation
rsync --version

Expected output:

rsync  version 3.3.0  protocol version 31

Basic Syntax

rsync [OPTIONS] SOURCE DESTINATION

Important Notes:

  • Trailing slash matters!
    • rsync -av /source/ /dest/ - copies contents of source
    • rsync -av /source /dest/ - copies source directory itself

Most Useful Daily Commands

1. Basic Local Copy

rsync -av /source/ /destination/
  • -a = archive mode (preserves permissions, timestamps, etc.)
  • -v = verbose (shows files being transferred)

2. Copy with Progress Bar

rsync -av --progress /source/ /destination/

Shows real-time transfer progress.

3. Dry Run (Test Before Executing)

rsync -av --dry-run /source/ /destination/

Shows what would be transferred without actually doing it.

4. Delete Files in Destination Not in Source

rsync -av --delete /source/ /destination/

Makes destination an exact mirror of source.

5. Copy Over SSH (Remote Sync)

rsync -avz -e ssh user@remote:/path/to/source/ /local/destination/
  • -z = compress during transfer
  • -e ssh = use SSH protocol

6. Exclude Files/Directories

rsync -av --exclude='*.tmp' --exclude='cache/' /source/ /destination/

7. Include Only Specific Files

rsync -av --include='*.jpg' --exclude='*' /source/ /destination/

8. Resume Interrupted Transfer

rsync -av --partial --progress /source/ /destination/
  • --partial = keep partially transferred files

9. Backup with Timestamp

rsync -av /source/ /backup/$(date +%Y%m%d)/

10. Show Total Transfer Statistics

rsync -av --stats /source/ /destination/

Common Options

Option Description
-a, --archive Archive mode (recursive, preserves everything)
-v, --verbose Increase verbosity
-r, --recursive Recurse into directories
-u, --update Skip files newer on destination
-z, --compress Compress file data during transfer
-h, --human-readable Output numbers in human-readable format
-P Same as --partial --progress
-n, --dry-run Perform trial run without changes
--delete Delete files not in source
--exclude=PATTERN Exclude files matching pattern
--include=PATTERN Include files matching pattern
--max-size=SIZE Don’t transfer files larger than SIZE
--min-size=SIZE Don’t transfer files smaller than SIZE
--backup Make backups of existing files
--stats Show file transfer statistics
-e ssh Specify SSH as remote shell

Practical Examples

Example 1: Backup Photos to External Storage

# Backup all photos from DCIM to external SD card
rsync -avh --progress ~/storage/dcim/ /sdcard/Backups/Photos/

# With exclusions
rsync -avh --progress \
  --exclude='*.thumbnails' \
  --exclude='.trashed' \
  ~/storage/dcim/ /sdcard/Backups/Photos/

Example 2: Sync Documents Between Devices

# From Termux to remote server
rsync -avz -e ssh ~/Documents/ user@192.168.1.100:/home/user/mobile-docs/

# From remote server to Termux
rsync -avz -e ssh user@192.168.1.100:/home/user/docs/ ~/Documents/

Example 3: Incremental Backup with Date

# Create dated backup directory
BACKUP_DIR="/sdcard/Backups/$(date +%Y-%m-%d)"
rsync -avh --progress ~/storage/shared/ "$BACKUP_DIR/"

Example 4: Mirror Directory (Exact Copy)

# Make destination identical to source
rsync -avh --delete --progress /source/ /destination/

Example 5: Copy Only Modified Files

# Update only changed files (don't overwrite newer files)
rsync -avu --progress /source/ /destination/

Example 6: Bandwidth Limiting

# Limit transfer to 1000 KB/s
rsync -av --bwlimit=1000 /source/ /destination/

Example 7: Exclude Multiple Patterns

rsync -av \
  --exclude='*.tmp' \
  --exclude='*.cache' \
  --exclude='node_modules/' \
  --exclude='.git/' \
  ~/Projects/ /sdcard/Backups/Projects/

Example 8: Copy Only Specific File Types

# Backup only images
rsync -av \
  --include='*/' \
  --include='*.jpg' \
  --include='*.png' \
  --include='*.gif' \
  --exclude='*' \
  ~/storage/shared/ ~/Backups/Images/

Example 9: Resume Large File Transfer

# If transfer was interrupted, resume it
rsync -avP /large-files/ /destination/

Example 10: Sync with Size Limits

# Only sync files between 1KB and 10MB
rsync -av \
  --min-size=1K \
  --max-size=10M \
  /source/ /destination/

Advanced Use Cases

Automated Backup Script

#!/data/data/com.termux/files/usr/bin/bash

# backup-script.sh
SOURCE="$HOME/storage/shared/Important"
DEST="/sdcard/Backups/Important-$(date +%Y%m%d_%H%M%S)"
LOG_FILE="$HOME/backup.log"

echo "Starting backup at $(date)" >> "$LOG_FILE"

rsync -avh \
  --progress \
  --stats \
  --exclude='*.tmp' \
  --exclude='cache/' \
  "$SOURCE/" "$DEST/" >> "$LOG_FILE" 2>&1

if [ $? -eq 0 ]; then
    echo "Backup completed successfully at $(date)" >> "$LOG_FILE"
else
    echo "Backup failed at $(date)" >> "$LOG_FILE"
fi

Make it executable:

chmod +x backup-script.sh

Sync with Remote Server Using SSH Key

# First, set up SSH key (if not already done)
ssh-keygen -t rsa -b 4096
ssh-copy-id user@remote-server

# Then sync without password prompt
rsync -avz -e "ssh -i ~/.ssh/id_rsa" \
  ~/Documents/ \
  user@remote-server:/backup/mobile/

Two-Way Sync (Bidirectional)

# Sync from local to remote
rsync -avzu /local/path/ user@remote:/remote/path/

# Sync from remote to local
rsync -avzu user@remote:/remote/path/ /local/path/

⚠️ Warning: This doesn’t handle conflicts automatically. Use with caution.

Tips for Termux Users

1. Storage Permissions

# Grant storage access to Termux first
termux-setup-storage

2. Common Termux Paths

  • Internal storage: ~/storage/shared/ or /sdcard/
  • Downloads: ~/storage/downloads/
  • DCIM (Camera): ~/storage/dcim/
  • Documents: ~/storage/documents/

3. Testing Commands Safely

Always use --dry-run first:

rsync -av --dry-run /source/ /destination/

4. Monitoring Progress

For large transfers, use:

rsync -avh --progress --stats /source/ /destination/

5. Dealing with Special Characters

Use quotes around paths with spaces:

rsync -av "/path/with spaces/" "/another path/"

6. Network Transfers

For WiFi transfers between devices, ensure both are on the same network and SSH server is running on the destination.

Troubleshooting

Issue: “Permission denied”

Solution:

# Check permissions
ls -la /path/to/directory

# Grant storage access in Termux
termux-setup-storage

# Use appropriate user permissions
rsync -av --chmod=ugo=rwX /source/ /destination/

Issue: “Connection refused” (remote sync)

Solution:

# Ensure SSH is running on remote device
# In Termux, install and start SSH:
pkg install openssh
sshd

# Check SSH port (default 8022 in Termux)
rsync -av -e "ssh -p 8022" /source/ user@remote:/dest/

Issue: Transfer is too slow

Solution:

# Use compression for network transfers
rsync -avz /source/ /destination/

# Or disable compression for local transfers
rsync -av --no-compress /source/ /destination/

Issue: “rsync: command not found”

Solution:

pkg update
pkg install rsync

Issue: Files not being deleted with –delete

Solution:

# Ensure correct syntax (source has trailing slash)
rsync -av --delete /source/ /destination/

# Check dry-run first
rsync -av --delete --dry-run /source/ /destination/

Quick Reference Card

Essential Command Template

rsync -avh --progress [--delete] [--exclude='pattern'] /source/ /destination/

Most Used Options Combination

# Local backup with progress
rsync -avhP /source/ /backup/

# Remote sync compressed
rsync -avzP -e ssh /local/ user@remote:/path/

# Exact mirror (delete extra files)
rsync -avh --delete /source/ /mirror/

# Safe test run
rsync -avn /source/ /destination/

Additional Resources

Version History Notes

rsync 3.3.0 (April 2024) - Latest

  • Improved performance for large file transfers
  • Enhanced support for extended attributes
  • Better error reporting and handling
  • Security improvements

Key Changes from 3.2.x to 3.3.0:

  • New --copy-as option for permission handling
  • Improved --mkpath functionality
  • Enhanced checksum algorithms
  • Better handling of symbolic links

Created for Termux users | Updated October 2025


---

## How to Use This Guide

### Step 1: Save the Markdown File
```bash
# In Termux, create the file
nano rsync-guide.md

# Paste the content above, then save with Ctrl+X, Y, Enter

Step 2: View the Guide Anytime

# Install a markdown viewer (optional)
pkg install mdcat

# View with formatting
mdcat rsync-guide.md

# Or use basic cat/less
less rsync-guide.md

Step 3: Start with Basic Examples

Example 1: Backup Your Documents

# First, check what will be copied (dry run)
rsync -avn ~/Documents/ ~/storage/shared/Backups/Documents/

# If looks good, do the actual sync
rsync -avh --progress ~/Documents/ ~/storage/shared/Backups/Documents/

Example 2: Sync Photos to SD Card

# Backup camera photos
rsync -avh --progress ~/storage/dcim/Camera/ /sdcard/PhotoBackup/

Example 3: Mirror a Directory

# Make an exact copy (including deletions)
rsync -avh --delete --progress ~/Important/ ~/Important_Backup/

Step 4: Practice with Dry Runs

Before any major operation, always test first:

rsync -avn [your-options] /source/ /destination/

The -n flag shows what would happen without actually doing it.

Step 5: Create Your Own Backup Script

# Create a simple backup script
nano my-backup.sh

Add this content:

#!/data/data/com.termux/files/usr/bin/bash

# Simple backup script
echo "Starting backup..."

rsync -avh --progress \
  --exclude='*.tmp' \
  ~/storage/shared/Important/ \
  ~/storage/shared/Backups/Important-$(date +%Y%m%d)/

echo "Backup completed!"

Make it executable:

chmod +x my-backup.sh
./my-backup.sh

Key Concepts Explained

1. Archive Mode (-a)

This is equivalent to: -rlptgoD

  • r = recursive (include subdirectories)
  • l = copy symlinks as symlinks
  • p = preserve permissions
  • t = preserve modification times
  • g = preserve group
  • o = preserve owner
  • D = preserve device files and special files

2. Trailing Slash Difference

# WITH trailing slash - copies CONTENTS
rsync -av /source/ /dest/
# Result: /dest/file1, /dest/file2

# WITHOUT trailing slash - copies DIRECTORY
rsync -av /source /dest/
# Result: /dest/source/file1, /dest/source/file2

3. Delete Option Behavior

rsync -av --delete /source/ /destination/
  • Deletes files in destination that don’t exist in source
  • Makes destination an exact mirror
  • Use with caution! Test with --dry-run first

4. Exclude vs Include

# Exclude specific patterns
rsync -av --exclude='*.tmp' /source/ /dest/

# Include only specific files (exclude everything else)
rsync -av --include='*.pdf' --exclude='*' /source/ /dest/

# Complex filtering
rsync -av \
  --include='*/' \
  --include='*.jpg' \
  --include='*.png' \
  --exclude='*' \
  /source/ /dest/

Safety Checklist

Before running any rsync command:

  1. ✅ Always use --dry-run first with new commands
  2. ✅ Double-check source and destination paths
  3. ✅ Be careful with --delete flag - it permanently removes files
  4. ✅ Check trailing slashes - they change behavior
  5. ✅ Test with small directory first before large operations
  6. ✅ Have backups of important data before major syncs
  7. ✅ Verify permissions on destination directory

This guide covers everything you need for daily rsync usage in Termux as of 2025. The information is based on the latest rsync version 3.3.0 and official documentation.

Sources: