227
FTP
227 Entering Passive Mode
Entering Passive Mode. The server provides an IP address and port number for the client to connect to for data transfer, formatted as (h1,h2,h3,h4,p1,p2).
이 코드를 보게 되는 경우
After issuing the PASV command. The server switches to passive mode and tells the client where to connect for data transfer.
해결 방법
No fix needed — parse the IP and port from the response to establish the data connection. If connections fail, check NAT/firewall rules on the passive port range.
비교
비교 대상
가이드
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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