Port 873: rsync
Port 873 is rsync, used by the rsync daemon to synchronize files and directories efficiently by transferring only the parts of a file that changed. Most rsync usage today tunnels over SSH on port 22 instead, but the standalone daemon still listens here.
| Port number | 873 |
|---|---|
| Service | rsync file synchronization |
| Protocol | TCP |
| Category | File transfer |
| Default encryption | No |
Frequently asked questions
What is port 873 used for?
Port 873 is rsync, used by the rsync daemon to synchronize files and directories efficiently by transferring only the parts of a file that changed. Most rsync usage today tunnels over SSH on port 22 instead, but the standalone daemon still listens here.
Is port 873 TCP or UDP?
Port 873 (rsync) uses TCP.
Is port 873 secure?
Port 873 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 873 on my firewall?
Only if you specifically need rsync. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.