Thanks for all your replies. I got in touch with IBM, and WebSphere has a setting for this afterall. It's called "Extended Handshake" and enabling it will allow the plugin to do more extensive testing. I assume that means it will check the HTTP return code in addition to the port knock. I tested it out, and it works flawlessly. So, once again thank you very much for all your assistance. R. --- Axel-Stéphane SMORGRAV <Axel-Stephane.SMORGRAV@xxxxxxxxxxxxxx> wrote: > You are right. It does do port checks. Too bad it > cannot determine that the application server is > unavailable based on the HTTP 502 the reverse proxy > would return in that case, and take the server off > the list... Did you actually verify that? > > Truly, we abandoned using WebSphere and WebLogic > plugins long time ago and have since been using > hardware load balancers that basically offer the > same functionality as the plugins but are a lot more > flexible in the way they can be configured. The load > balancers do not do port checks (except in the case > of SSL). Instead they pull a static page from the > HTTP server (Apache, IIS, J2EE or whatever). If you > insert an additional reverse proxy in between, it > will still detect whether the application backend is > available or not based on whether the status page is > served. > > -ascs > > > -----Original Message----- > From: Richard de Vries > [mailto:richard_devries@xxxxxxxxx] > Sent: Wednesday, June 28, 2006 8:05 PM > To: users@xxxxxxxxxxxxxxxx > Subject: RE: [users@httpd] Reverse Proxy between > WebSphere and the WebServer - prevent "Bad Gateway" > errors. > > True, it does routing and does simple port-checks I > think to make sure the backend application server is > up. If that backend server is down, it routes the > request to an app server that is up. > > In the proxy'd environment, this can happen: > > a) the backend app server crashes / goes down > b) the plugin, not knowing it's actually hitting a > reverse proxy, does a port check and says "Hey, the > WAS instance is up, let me send this request to > you". > c) the proxy tries to pass the request on to the > app, gets no response, and returns a "bad gateway" > error message which in turn is presented back to the > client. > > Without a proxy in the middle, this would happen: > > a) the backend app server crashes / goes down > b) the plugin tries to talk to the app server, sees > its down, and reroutes the request to a different > app server. The client gets the right data back and > would be none-the-wiser. > > So, how would I accomplish the latter with using the > former? > > --------------------------------------------------------------------- > The official User-To-User support forum of the > Apache HTTP Server Project. > See <URL:http://httpd.apache.org/userslist.html> for > more info. > To unsubscribe, e-mail: > users-unsubscribe@xxxxxxxxxxxxxxxx > " from the digest: > users-digest-unsubscribe@xxxxxxxxxxxxxxxx > For additional commands, e-mail: > users-help@xxxxxxxxxxxxxxxx > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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