Supported Kong Router Flavors

Kong Gateway (open-source and enterprise edition) includes an expression-based router in versions 3.0 and later. The router can be configured in the following modes:

• traditional: uses the pre-3.0 router.
• traditional_compatible: uses the expression based router, but the router configuration interface remains the same as traditional.
• expressions: uses the expression-based router, and expressions must be provided in the router configuration interface.

The compatibilities of router flavors between different Kubernetes Ingress Controller versions and Kong Gateway are shown in the following table. Kubernetes Ingress Controller in versions 2.6.x and lower does not support Kong Gateway 3.0 and later, so the version of Kubernetes Ingress Controller begins at 2.7.x.

Kubernetes Ingress Controller	2.7.x	2.8.x	2.9.x
Kong 3.0.x traditional
Kong 3.0.x traditional_compatible	(*)	(*)	(*)
Kong 3.0.x expressions
Kong 3.1.x traditional
Kong 3.1.x traditional_compatible	(*)	(*)	(*)
Kong 3.1.x expressions

(*) Most use cases are supported. Regexes with a backslash (\) followed by a non-escaped character (for example, \j or \/) in matches of paths or headers may not be accepted when Kong Gateway 3.0 is configured to use the traditional_compatible router.