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Forum Discussion

Karthick1's avatar
Karthick1
Icon for Cirrus rankCirrus
Dec 05, 2025

F5 XC 503 upstream_reset_before_response_started{protocol_error}

Hello Community, I would like to share some additional information regarding the 503 response code in F5 XC. When the origin server sends a response to XC that is not compliant with HTTP RFC standar...
503
Envoy
f5xc
http response codes
Nikoolayy1's avatar
Nikoolayy1
Icon for MVP rankMVP
Dec 08, 2025

Thanks for sharing ! Maybe if you gather more you can make a community article as I see a value Community Articles | DevCentral  as XC doesn't have the same level of documentation as BIG-IP or Nginx.