---
title: "rsync — Fast, Resumable File Transfers"
domain: opensource
category: dev-tools
tags: [rsync, backup, file-transfer, linux, cli]
status: published
created: 2026-04-02
updated: 2026-04-02
---
# rsync — Fast, Resumable File Transfers

## Problem

Copying large files or directory trees between drives or servers is slow, fragile, and unresumable with `cp`. A dropped connection or a single error means starting over. You also want to skip files that already exist at the destination without re-copying them.

## Solution

`rsync` is a file synchronization tool that only transfers what has changed, preserves metadata, and can resume interrupted transfers. It works locally and over SSH.

### Installation (Fedora)

```bash
sudo dnf install rsync
```

### Basic Local Copy

```bash
rsync -av /source/ /destination/
```

- `-a` — archive mode: preserves permissions, timestamps, symlinks, ownership
- `-v` — verbose: shows what's being transferred

**Trailing slash on source matters:**
- `/source/` — copy the *contents* of source into destination
- `/source` — copy the source *directory itself* into destination

### Resume an Interrupted Transfer

```bash
rsync -av --partial --progress /source/ /destination/
```

- `--partial` — keeps partially transferred files so they can be resumed
- `--progress` — shows per-file progress and speed

### Skip Already-Transferred Files

```bash
rsync -av --ignore-existing /source/ /destination/
```

Useful when restarting a migration — skips anything already at the destination regardless of timestamp comparison.

### Dry Run First

Always preview what rsync will do before committing:

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

No files are moved. Output shows exactly what would happen.

### Transfer Over SSH

```bash
rsync -av -e ssh /source/ user@remotehost:/destination/
```

Or with a non-standard port:

```bash
rsync -av -e "ssh -p 2222" /source/ user@remotehost:/destination/
```

### Exclude Patterns

```bash
rsync -av --exclude='*.tmp' --exclude='.Trash*' /source/ /destination/
```

### Real-World Use

Migrating ~286 files from `/majorRAID` to `/majorstorage` during a RAID dissolution project:

```bash
rsync -av --partial --progress --ignore-existing \
  /majorRAID/ /majorstorage/ \
  2>&1 | tee /root/raid_migrate.log
```

Run inside a `tmux` or `screen` session so it survives SSH disconnects:

```bash
tmux new-session -d -s rsync-migrate \
  "rsync -av --partial --progress /majorRAID/ /majorstorage/ | tee /root/raid_migrate.log"
```

### Check Progress on a Running Transfer

```bash
tail -f /root/raid_migrate.log
```

---