451
FTP
451 Local Error
Requested action aborted: local error in processing. The server encountered an unexpected error while trying to complete the command.
Quando você vê este código
When the server has an internal issue like a disk I/O error, memory shortage, or filesystem problem during command processing.
Como corrigir
Retry the command. If the error persists, contact the server administrator to check disk health, available memory, and server logs.
Especificação
Comparar com
Guias
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
Cenários de depuração
Glossário
Status Code
TLS Handshake
TCP/IP
Three-Way Handshake
Port Number
Firewall
Proxy Server (Forward Proxy)
Socket
Request-Response Model
RFC (Request for Comments)
Connection-Oriented
Half-Duplex
Text vs Binary Protocol
FTP Active Mode
FTP Passive Mode
FTP Control Channel
FTP Data Channel
SFTP (SSH File Transfer Protocol)
FTPS (FTP Secure)
FTP Reply Code
FTP Anonymous Access
FTP Transfer Mode (ASCII vs Binary)
FTP Resume (REST Command)
SCP (Secure Copy Protocol)
FTP Chroot Jail
WebDAV (Web Distributed Authoring and Versioning)
rsync
FTP MLSD (Machine-Readable Listing)
FTP NAT Traversal
Transfer Integrity
FTP over TLS (RFC 4217)
File Locking
Bandwidth Throttling
TLS Versions