-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Martin,
On 3/22/18 6:58 AM, Martin Knoblauch wrote: > we have this annoying problem that although Tomcat workers are set > to DIS state in mod_jk, there are new connections being opened. > This prevents us from "idle down" Tomcats in a timely fashion. This > hurts when a restart is needed. While our empathy for human clients > is pretty limited, we care a lot about our automated workloads :-) > > Our setup: Apache 2.4.x frontend -> mod_jk(1.2.42) balancer, > sticky sessions -> a bunch of Tomcat 7 (yes I know. Oldie but > Goldie :-) workers. > > As far as I understand, the problem arises with HTTP(S) clients > that cache the session cookies. If such a client tries to open a > new connection to the backend, the old cookie passes to a DIS > worker even if it is no longer valid on the Tomcat side. > Tomcat/Application then sees that the cookie is not valid and doles > out a new cookie which then allows the new connection to be > established. > > My idea is now to delete existing session cookies for certain > request pattern on the Apache frontend. If it works, it should > force mod_jk to a new ACT Tomcat. But I am nor really fond of > messing with the Apache configuration, as the reason lies on the > mod_jk/Tomcat side. > > So if anybody has another suggestion I would love to hear it. > Before I forget, changing the application itself is not an option. My suggestion is to use the LoadBalancerDrainingValve[1][2]. It was written for this exact purpose. It's currently only available in Tomcat 9.0.x, but you should be able to use it for previous Tomcat versions as the Valve/Request/Response interfaces shouldn't have changed in any incompatible ways between those versions. Hope that helps, - -chris [1] https://tomcat.apache.org/tomcat-9.0-doc/config/valve.html#Load_Balancer _Draining_Valve [2] https://tomcat.apache.org/tomcat-9.0-doc/api/org/apache/catalina/valves/ LoadBalancerDrainingValve.html -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQJRBAEBCAA7FiEEMmKgYcQvxMe7tcJcHPApP6U8pFgFAlqzurodHGNocmlzQGNo cmlzdG9waGVyc2NodWx0ei5uZXQACgkQHPApP6U8pFjpfBAAyuM5kfF/ukIcnJjd NRoxyMIZtuKrVOht8tXn3or5ONye71Q/iZ3vd8UVlbrGurHWdi3ADH2n7Cvss8oX +02XSRzkW4EAmtu0Ailpc5PBDW0j3ASZTqnkymtNyBjQ8MDQkYtizPql51SU6tOp CaG4RP8TlEP91qI+nldCWMT+YbnAmAlEHvGOAJ1MzEKjmi14AfT8e4guBu2dfRCt QXderPV9imVveBmP53Z3WklPDCRMfEmGCdUf25Be/5ZnUGDZ5wmAZl3l/HLnUBAD tOwEBBCsm2OeVpvbbWj815ngnB/NkCC6gleePGN8J3HysJY+fnmPUl6Cw0t8jV3T CbqUlXJfH54QRvzie+1eGXGK1iwX3++icfecusC2Rea/9of+s65OVCFoJVkHj1qY 3T/tWZm0dbqLqAbadE7/2ihrOPBg3VnW/vdD+/lKXBEv/ECH/9nYNY3OkY6mJ3KS ptaKCdojTh1KCqxqilxfYEBMc9YFh1AoW/GYoF41mqFKRWc0CMLakCuNrm2vT8L0 u+KiFo8bPnuJ9Sw4jjKS2a52yp1jcJCjXnsDyO3vn7t3MNvyfygcbQR6Jftdq441 imwYVdwJTwULiR45cL6/AtGDSgKr1L4LhtcyhCzfxBRJh24W8u3dataH0loEVCup uAZ1f50984WWHJMJYmI6UrA7lKI= =8fI4 -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
