221
FTP
221 Closing Control Connection
Service closing control connection. The server is logging out and closing the session in response to a QUIT command.
On this page
When You See This Code
After issuing the QUIT command to gracefully disconnect from the FTP server.
How to Fix
No fix needed — the session has ended normally. Reconnect with a new session if needed.
Specification
Compare With
Guides
FTP Reply Codes: Understanding File Transfer Responses
DNS & Networking
TCP Three-Way Handshake and Connection Lifecycle
DNS & Networking
Essential Network Debugging Tools: ping, traceroute, mtr, and tcpdump
DNS & Networking
RFC 959: FTP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
Protocol Deep Dives
Migrating from FTP to SFTP: A Complete Transition Guide
Migration & Upgrades
HTTP Access Log Management: Rotation, Parsing, and Analysis
Production Infrastructure
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FTP over TLS (RFC 4217)
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Frequently Asked Questions
What is FTP 221 Closing Control Connection?
Service closing control connection. The server is logging out and closing the session in response to a QUIT command.
When do you see FTP 221 Closing Control Connection?
After issuing the QUIT command to gracefully disconnect from the FTP server.
How to fix FTP 221 Closing Control Connection?
No fix needed — the session has ended normally. Reconnect with a new session if needed.