Hi Chris, A follow-up. I found the following discussion, which goes back to October 19, 2011:
http://tomcat.10.x6.nabble.com/Reuse-mod-ajp-proxy-connections-td2096715.html I think it is relevant to this issue. Back then, one Dimitar said: >> "My understanding of the *reuse* flag in AJP13_END_RESPONSE >> structure is that this flag is hard coded and cannot be controlled >> by configuration settings. I couldn't find any in Tomcat AJP >> connector configuration that could do that." You responded with: >> "I'm no expert, but seeing keepalives disabled for a proxy connection >> would sure make me think that maybe that setting is disabling, ya >> know, the keepalive-style connection that AJP is supposed to maintain. >>... I'd try NOT disabling keepalives and see if that helps." In our set-up, the settings for socket_keepalive is false by default. So, we're now going to add the line worker.workerName.socket_keepalive=true to the workers.properties file and see what happens. Kind regards, Alfred -----Oorspronkelijk bericht----- Van: Alfred Bakia <alfredba...@uitgeverij-deviant.nl> Verzonden: 17 June 2020 19:08 Aan: Tomcat Users List <users@tomcat.apache.org> Onderwerp: RE: Warning "AJP13 protocol: Reuse is set to false" written logs every second of every day. Please help. Hi Chris, Thanks for your reply. Thanks also for your warning against interfering with the setting allowedRequestAttributesPattern ('Setting the value to ".*" is a violation of sane security policy'). I guessed as much, and am grateful for your confirmation. On the subject of mod_jk, we are apparently talking about the same thing. In our set-up the mod_jk log is called isapi_redirect.log. The code that generates the error is indeed /native/common/jk_ajp_common.c. The part where the error is generated is: case JK_AJP13_END_RESPONSE: ae->reuse = (int)jk_b_get_byte(msg); if (!ae->reuse) { /* * AJP13 protocol reuse flag set to false. * Tomcat will close its side of the connection. */ jk_log(l, JK_LOG_WARNING, "(%s) AJP13 protocol: Reuse is set to false", ae->worker->name); } This code snippet says that reuse is determined - at the end of a response - from a byte obtained from some message. Which raises two questions: 1) The response to the "ping" REST request has status code 204 ("No Content"). If, as you say, a 204 response is OK, then where would the reuse byte come from? 2) Do you know a way to set the "AJP13 protocol reuse flag" to true? As far as we know, the only "reuse" settings at our disposal are the current worker settings, worker.workerName.connection_pool_size=500 and worker. workerName.max_reuse_connections=250. Kind regards, Alfred -----Oorspronkelijk bericht----- Van: Christopher Schultz <ch...@christopherschultz.net> Verzonden: 16 June 2020 19:55 Aan: Tomcat Users List <users@tomcat.apache.org> Onderwerp: Re: Warning "AJP13 protocol: Reuse is set to false" written logs every second of every day. Please help. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Alfred, On 6/15/20 09:45, Alfred Bakia wrote: > Thanks, Chris. To respond to your remarks: > > 1) The warnings, "AJP13 protocol: Reuse is set to false", are being logged by Tomcat (in the Tomcat AJP connector logs). Weird. I can't find that string anywhere in code or other files in Tomcat, but its right there in mod_jk: ./native/common/jk_ajp_common.c: jk_log(l, JK_LOG_WARNING, "(%s) AJP13 protocol: Reuse is set to false", Are you sure you are looking at the right log file? > 2) As I mentioned earlier, the versions and settings of the servers > (and their respective IIS web servers) are the same. > > In any case I have discovered "how" the warning occurs. It is indeed > triggered by the REST API. > > The culprit is a REST request in the form: > > http://www.ourdomain.com/api/srv2/exercises/93/1431/26346/ping > > It is a POST request and "ping" is a custom REST method. It is just a > ping, so the status code of the response is 204 ("No Content"). A 204 response should not cause any problem. > I can confirm that every ping request results in the warning > "AJP13 protocol: Reuse is set to false" being written to Tomcat's > connector logs. > > Researching this on the web, I found the suggestion to add > allowedRequestAttributesPattern=".*" to the AJP connector in > server.xml. > > Is this a viable solution? This has nothing to do with your REST API. This is a change made to recent versions of Tomcat that may require you to allow certain non-standard variables to be passed-over from your web server to Tomcat via AJP. If your "ping" REST API is requiring some information to be passed from the web server to Tomcat and you are seeing errors on the Tomcat side, then you may have to fiddle with the allowedRequestAttributesPattern. Setting the value to ".*" is a violation of sane security policy. But I see no evidence that your "Reuse is set to false" error is related (yet) to the allowedRequestAttributesPattern. If you see errors in the Tomcat log, please post them and we'll see. The allowedRequestAttributesPattern wasn't added to Tomcat until 9.0.31 so if you really are running 9.0.21, then adding allowedRequestAttributesPattern will accomplish nothing. - -chris -----BEGIN PGP SIGNATURE----- Comment: Using GnuPG with Thunderbird - https://www.enigmail.net/ iQIzBAEBCAAdFiEEMmKgYcQvxMe7tcJcHPApP6U8pFgFAl7pB3wACgkQHPApP6U8 pFg97w//T8XVtWlic/x/nUJHZUXfDs99Ou8cKcSFFI/AbBldd5k8vSxCTKg40wON 3bUooWG5GWZhVRNHH2JH0eyiKqhLmDtAzdnSp7xAkAW2fAZ2Zlv0VLb0AzJCTqRg e1Nd9R9Ii9mjcSU5+M2WrNSourUhOT0FVYaqpvlaN89XyetHSuVIUladDuwM8kFN 3ngAtkgmIYfxXcqIPXjoNZ+s8cr1MB0qk+KkiXyOCb8XgfmZUkBMRncgqMAgEff5 p6Z/1jGVv0+S7E0+HV1yqJpakiGjVswfIjbc2s89YnVL6bvyBqUnJl4HrmOHY0bV d3O/NQ3+vZ/Kma4e84TI5QKQx0KvQj0oBH41fFl0WmPjraKjGMTTfMCy9BjvLwdf hbTEbZaBRvn7Tr+iR5ksrvaJTxZD1ABMb7o0uksCsPQO8h3tl3s7L5O4g0P3+7kV /SiqDD+WyqkhmJuX86Y3MtSeMUTsg9RiXOZLLGF59TOZFeso/2O+OWYU/uImXw2X opWW38Vowhn8O9a94RbRA67EvJFiLdWwTDoLlnVP0ZxGkdOIow0EQWfnCDKaBXOd l+BdTG7zPbU8I3bw00cXGytyCYENt9uIZJ/XVVkyC2EAFAbEArVjWR0ocZT4W6zQ bCc5vbHFJnNvCRh8jeSl9ORSzBFzYPt0B1kvSMkNE0U7y7mU74c= =8kiV -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
