Kong Ingress Controller logs error: "http2 requests not supported yet"

We see Kong Ingress Controller logging messages frequently such as the following:

time="2026-09-07T18:07:05Z" level=error msg="checking config status failed: %!w(*kong.APIError=&{500 An unexpected error occurred})"

In addition, we see the following stack traces thrown in the Kong Gateway proxy:

2026/09/07 16:36:11 [error] 2052#0: *4682600 [lua] api_helpers.lua:526: handle_error(): /usr/local/share/lua/5.1/lapis/application.lua:424: /usr/local/share/lua/5.1/kong/api/routes/health.lua:49: http2 requests not supported yet
stack traceback: [C]: in function 'capture' /usr/local/share/lua/5.1/kong/api/routes/health.lua:49: in function 'fn' /usr/local/share/lua/5.1/kong/api/api_helpers.lua:293: in function 'fn' /usr/local/share/lua/5.1/kong/api/api_helpers.lua:293: in function </usr/local/share/lua/5.1/kong/api/api_helpers.lua:276> stack traceback: [C]: in function 'error' /usr/local/share/lua/5.1/lapis/application.lua:424: in function 
'handler' 
127.0.0.1 - - [07/Sep/2026:16:36:11 +0000] "GET /status HTTP/2.0" 500 42 "-" "Go-http-client/2.0"

How do we resolve this issue?

This error occurred because the Kong Ingress Controller attempts to access the Kong Gateway Admin API /status endpoint over HTTP/2.0, which was not supported on that endpoint in older Kong Gateway versions.

This was a known issue discussed at GitHub Issue #2435 for the Kong Ingress Controller. A pull request (#8690) for Kong Ingress Controller was created to address this.

This issue is fixed on current Kong Gateway (confirmed on 3.14.0.0). The Admin API’s /status route no longer performs an internal ngx.location.capture subrequest that used to be incompatible with HTTP/2, and a live test against a Kong Gateway 3.14.0.0 node with the default admin_listen = ... 8444 http2 ssl now returns a clean 200 for GET /status HTTP/2.0, with no error logged. If you are on Kong Gateway 3.14.0.0 (or any reasonably current version), you should not see this error at all, and no workaround is needed.

If you are still on an older, affected Kong Gateway version, the same two workarounds still apply:

1) Ignore the issue; it only results in log noise and does not affect functionality.

2) If ignoring is not possible, disable HTTP/2.0 on the Admin API by removing http2 from the admin_listen property. Refer to the documentation for more details.

The best long-term fix is to upgrade to a current Kong Gateway version, where this no longer occurs.