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506
HTTP 506 Variant Also Negotiates
5xx Server Error
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- HTTP Status Codes
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5xx Server Error
RFC 2295, Section 8.1
What is HTTP 506 Variant Also Negotiates?
The 506 (Variant Also Negotiates) status code indicates that the server has an internal configuration error where the chosen variant resource is configured to engage in transparent content negotiation itself, creating an infinite negotiation loop.
Common Use Cases
- Misconfigured content negotiation
- Variant configuration errors
Usage Example
If you encounter 506 errors while configuring content negotiation in Apache, check your type-map files and ensure variant resources do not point to other negotiated resources. Restructure the content negotiation hierarchy to prevent circular references.
# Apache - check for circular type-map references
# Ensure .var files do not point to other .var files
# Example type-map:
URI: index
URI: index.html
Content-Type: text/html
URI: index.pdf
Content-Type: application/pdfRelated Status Codes
Last updated: 17 Aug 2026
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