Port 2375 — Docker API (plain)

TCP registered

What runs on port 2375

The Docker daemon REST API without TLS.

Security considerations

Exposing this is equivalent to handing out root on the host. It is one of the most scanned ports on the internet for exactly that reason. Use the Unix socket, or 2376 with client certificates.

Checking whether something is listening

# Linux / macOS — what is bound to the port
sudo lsof -i :2375
sudo ss -lntp | grep :2375

# Windows
netstat -ano | findstr :2375
Get-NetTCPConnection -LocalPort 2375

# is it reachable from outside?
nc -zv example.com 2375
curl -v telnet://example.com:2375

Freeing the port

# find the process, then stop it
sudo lsof -ti :2375 | xargs kill        # Linux / macOS
netstat -ano | findstr :2375            # note the PID, then:
taskkill /PID <pid> /F                    # Windows

Other common ports

• Port 20 — FTP data
• Port 21 — FTP control
• Port 22 — SSH / SFTP
• Port 23 — Telnet
• Port 25 — SMTP
• Port 53 — DNS
• Port 67 — DHCP server
• Port 68 — DHCP client
• Port 69 — TFTP
• Port 80 — HTTP
• Port 110 — POP3
• Port 123 — NTP
• Port 143 — IMAP
• Port 161 — SNMP
• Port 389 — LDAP
• Port 443 — HTTPS
• Port 445 — SMB
• Port 465 — SMTPS

All port numbers