504
SIP
504 Server Time-out
The server did not receive a timely response from an external server it accessed while attempting to process the request. Different from 408 (client timeout).
Quando você vê este código
When a proxy's request to a downstream server times out. The proxy itself is working, but the next hop is unresponsive.
Como corrigir
Check the downstream server's availability. Verify DNS resolution for the next-hop domain. Consider adjusting transaction timeout values.
Especificação
Equivalentes entre protocolos
Comparar com
Guias
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Security & Authentication
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Real-Time Protocols
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Real-Time Protocols
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Protocol Deep Dives
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Protocol Deep Dives
Cenários de depuração
Glossário
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Request Method (HTTP Verb)
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TCP/IP
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SRTP (Secure Real-time Transport Protocol)
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B2BUA (Back-to-Back User Agent)
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Codec Negotiation
SIP Response Classes
VoIP (Voice over IP)
Presence (SIP)
PBX (Private Branch Exchange)
MFA (Multi-Factor Authentication)
TLS Versions