although I'm not a commiter, I like to add 2 cents to the discussion. I like the idea of supporting JMX and the capbility of deploying a webapp without restarting the server. From the discussions so far, the task isn't simple, and may not fit the majority of users.
if 80% of the users don't have this need, justifying the extra features and possibly added complexity is debatable. Would it be sufficient to create a hook for more advanced mods? There are people using tomcat's admin tool to deploy/redeploy webapps, so having the feature in mod_proxy or whatever would make the edge cases less painful. using JMX would make managing a cluster of servers easier and reduce the need to login to every single server to stop, edit conf files, and restart. peter On Tue, 20 Jul 2004 08:18:39 -0700, Costin Manolache <[EMAIL PROTECTED]> wrote: > Well, the mod_proxy + enhancements for sticky session + enhancements for > passing auth info sounds reasonable - and if nobody wants the JMX > support, then maybe we won't need to write a new connector anyway :-) > > Remy will be happy - we'll only use the http connector. > > Costin > > > > Graham Leggett wrote: > > > Henri Gomez wrote: > > > >> jk was designed a long time ago so may be mod_proxy allready support > >> persistant connections. > > > > > > Persistence will happen on the backend on the condition there was > > persistence on the frontend. Generally the networks between backend and > > frontend are fast enough that connection setup is not a problem - a > > bigger problem is having expensive backend processes hanging around > > attached to a persistent connection that is not being used (assuming > > these connections are held by a tomcat thread of course, which may or > > may not be the case, not sure how tomcat is built internally). > > > >> Great. And if you handle in the proxy_loadbalancing.c > >> the JSESSION_ID, (sticky session) to map next requests > >> to the tomcat who set it, you'll have everything needed. > > > > > > Sticky sessions has been on my list of things to support for ages - > > perhaps a "proxy_sticky.c" module could take a single parameter (the > > name of the parameter and/or cookie) and keep track of which server > > served it. > > > > If you had redundant frontends you might have a mechanism to keep track > > of which server is handling which session stored in a shared mechanism. > > > > A separate module might keep track of which tomcat servers are up or > > down, removing a server from the list of available servers on certain > > events (connection refused, error 4xx, 5xx, whatever). > > > >> Well LDAP could be use for configuration outside a file. JMX/CMX goes a > >> bit farther since it let you update some characteristics at runtime. > >> > >> But I agree that providing a JMX/CMX facade to Apache 2.x modules will > >> be a good starting point. Costin will certainly clarify this point with > >> you. > >> > >> In fine the discussed mod_ajp module should detect topology change in a > >> second phase to learn for example that a tomcat in a cluster > >> started/stopped a web application, so next requests could be redirected > >> to another tomcat in the cluster. Also you should be able to update the > >> load factor for each tomcat, may be having a load factor by > >> Webapplication. > > > > > > In theory this kind of thing should not be limited to tomcat only, but > > to web applications (whether PHP, whatever) in general. > > > > Perhaps a mechanism that allows the backend to connect to the frontend > > and say "status has changed, I am offering webapp XXX now, so count me > > into the pool". Or a mechanism for the frontend to poll the > > characteristics of the backend so that it can autolearn what webapp can > > be found where (has the advantage of not requiring a special backend > > module, apart from a magic URL on the backend giving relevant the > > information) > > > > This opens up some interesting possiblities for "virtual mappings". > > Something like this: > > > > ProxyPass /myWebapp virtual://myWebbapp (or something) > > > > Where proxy can hand out the request to a backend that has recently said > > "hi proxy, I serve myWebapp, feel free to contact me to fulfil a request". > > > > Regards, > > Graham > > -- > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
