You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@trafficserver.apache.org by "vuori (via GitHub)" <gi...@apache.org> on 2025/02/11 10:09:26 UTC

[I] Stale negative responses returned under unknown conditions [trafficserver]

vuori opened a new issue, #12029:
URL: https://github.com/apache/trafficserver/issues/12029

   I have been seeing stale negative getting stuck in cache on ATS 10.0.2 and 10.0.3, but have been unable to reproduce this under controlled conditions. The problem has only been seen under relatively high loads, but it _might_ be that the issue occurs more often if the response is cached due to an internal request (from a Lua fetch call). Whatever the cause, the cached negative response is returned for all requests. Usually the cached response disappears after restarting ATS.
   
   Sample response:
   
   ```
   < HTTP/1.1 400 Bad Request
   < Cache-Control: public; max-age=30
   < Date: Mon, 10 Feb 2025 11:40:36 GMT
   < Content-Length: 0
   < Age: 866
   ```
   
   This is a relatively short-lived instance, sometimes the times go up to tens of hours for such response.
   
   The negative caching here is prompted only by the `Cache-Control` header. There are no `cache.config` pins for the origin so this shouldn't be https://github.com/apache/trafficserver/issues/7417 and `negative_caching_enabled` is set to 0. The above response was from a forward-proxied request with no remap entry, but the problem also occurs for remapped reverse-proxy requests.
   
   I have unfortunately not been able to gather debug logs for this, since it has only been seen on busy servers and seems to depend on in-memory state.


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org


Re: [I] Stale negative responses returned under unknown conditions [trafficserver]

Posted by "bneradt (via GitHub)" <gi...@apache.org>.
bneradt commented on issue #12029:
URL: https://github.com/apache/trafficserver/issues/12029#issuecomment-2679958396

   Thank you for your observations. It would be good to add autests for this. @cmcfarlen or I intend to do this at some point.


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org


Re: [I] Stale negative responses returned under unknown conditions [trafficserver]

Posted by "cmcfarlen (via GitHub)" <gi...@apache.org>.
cmcfarlen closed issue #12029: Stale negative responses returned under unknown conditions
URL: https://github.com/apache/trafficserver/issues/12029


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org


Re: [I] Stale negative responses returned under unknown conditions [trafficserver]

Posted by "vuori (via GitHub)" <gi...@apache.org>.
vuori commented on issue #12029:
URL: https://github.com/apache/trafficserver/issues/12029#issuecomment-2650683725

   I just noticed that the service suffering from the problem was returning a Cache-Control with an invalid separator (`;` instead of `,`). With a synthetic test, I can reproduce the error-is-cached-forever behavior when sending a similar malformed C-C.
   
   The fact that this C-C gets parsed to mean "cache this forever" seem like an unexpected result?


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org


Re: [I] Stale negative responses returned under unknown conditions [trafficserver]

Posted by "github-actions[bot] (via GitHub)" <gi...@apache.org>.
github-actions[bot] commented on issue #12029:
URL: https://github.com/apache/trafficserver/issues/12029#issuecomment-3956301182

   This issue has been automatically marked as stale because it has not had recent activity. Marking it stale to flag it for further consideration by the community.


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: issues-unsubscribe@trafficserver.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org