Hi, I'm looking for some advice on ensuring availability of an apache reverse proxy in an unusual setup. We host about 50 Tomcat servers in two data centers (more or less randomly ditributed) where each customer has his individual instance of a web application. Currently each customer accesses his application using http://servername/applicationXY (where XY is a sequential number). Our plan is to introduce a single URL space like http://ourservice/accountname and also terminate https with a frontend of Apache reverse proxies. A frontend will proxy requests for servers in the same data center with RewiteMaps (which are generated from the database of another application), and redirect requests for the other servers to the frontend in the other data center. The data centers are geographically differently located and have no direct connection, therefore we don't want proxying from one data center to the other. The frontends in both locations will have the same domain. Note that the Apaches don't do load balancing for the Tomcats, each request always goes to the Tomcat that contains the specific customer's application. So I don't need a sticky session mechanism based on session ids in URL or cookies. Also there is no caching involved, as most of the requests are either Web Service calls or they are redirected externally to customer's systems. Now my question: What do you recommend to ensure the availability of the Apaches within one data center? I will need at least two Apache machines per data center, but I don't expect a load higher than one of our usual machines could handle. So in principle, a hot standby/failover system would suffice. On the other hand, a load balancing system that detects and ignores a dead node also provides failover, makes better use of the second system, scales better from start and is easy to extend to more machines in case the load increases more than we foresee now. A separate load balancer would need to be redundant as well though, which means additional hardware costs. Can you recommend any load balancing software that would run on each Apache node without need for additional hardware? Or do you have any other comments/advice regarding this problem? Thanks Rainer Frey --------------------------------------------------------------------- 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
|