SCP
Contents
SCP (Secure Copy Protocol)
SCP (Secure Copy Protocol) is a command-line utility used to securely transfer files and directories between two computers over a network. It uses the SSH (Secure Shell) protocol to provide encryption and authentication, ensuring data confidentiality during transit.
SCP is available by default on most Unix-like operating systems, including Linux, macOS, and FreeBSD, and is widely used for remote file transfers to and from servers, including seedboxes, VPS servers, and cloud platforms.
Key Features
- **Encrypted transfer** – Uses SSH to securely transmit files
- **Authentication** – Supports password and public key login
- **Fast and reliable** – Good performance for bulk file transfers
- **Cross-platform support** – Available on Linux, macOS, and Windows (via third-party clients)
Basic Syntax
<syntaxhighlight lang="bash"> scp [options] [source] [destination] </syntaxhighlight>
Examples
Copy a local file to a remote server:
<syntaxhighlight lang="bash"> scp file.txt user@remote_host:/remote/directory/ </syntaxhighlight>
Copy a file from a remote server to the local machine:
<syntaxhighlight lang="bash"> scp user@remote_host:/remote/file.txt /local/directory/ </syntaxhighlight>
Copy an entire directory recursively:
<syntaxhighlight lang="bash"> scp -r /local/folder user@remote_host:/remote/directory/ </syntaxhighlight>
Use a custom port (e.g., 2222):
<syntaxhighlight lang="bash"> scp -P 2222 file.txt user@remote_host:/remote/path/ </syntaxhighlight>
SCP vs SFTP
While both SCP and SFTP use SSH and offer secure file transfers, there are key differences:
| Feature | SCP | SFTP | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Protocol | SSH-based | SSH-based | File transfer | Direct (fast, limited features) | Interactive (supports resume, list, delete) | Directory browsing | No | Yes | Resume transfers | No | Yes | GUI clients | Limited | Widely supported | Speed | Slightly faster | More robust | Scriptable | Yes | Yes |
Use Cases
- Uploading files to a remote server or seedbox
- Backing up configuration files from a remote VPS
- Securely copying logs, media, or documents over SSH
- Automating transfers with shell scripts or cron jobs
SCP Clients
- Native on Linux/macOS: `scp` in the terminal
- Windows: Use via
* PuTTY tools (e.g., `pscp.exe`) * WinSCP GUI client * MobaXterm with SCP integration
Security Considerations
- SCP inherits the security of SSH (strong encryption and authentication)
- Use SSH keys instead of passwords for improved security
- Ensure remote servers are configured with strong access controls and updated software
Deprecation Note
OpenSSH has deprecated the legacy SCP protocol in newer versions due to protocol vulnerabilities. The `scp` command still functions but may internally use SFTP when available. Users are encouraged to transition to `sftp` or `rsync` over SSH for secure, modern transfers.
Alternatives
- SFTP – Secure File Transfer Protocol
- rsync – Efficient file synchronization over SSH
- WebDAV – File access over HTTP/HTTPS
- FTP/FTPS – Legacy file transfer protocols
