Apache httpd作为jboss和其他Apache服务器的负载平衡器

Question

I have an apache httpd server, say server1* (publicly exposed) that is acting as load balancer for some jboss servers(behind firewall) using mod_cluster. Now I want to install my static content (images/css/htmls) and probably some cg-scripts on a couple of apache servers, say **server2 and server3 (behind firewall).

Now I want server1 to act as load balancer for these server2 and server3 as well along with the jboss servers.

With this arrangement, any request for applications deployed on jboss need to be routed to jboss and any static content request should go to server2 or server3 .

Here are the versions I am using

Linux Server apache httpd - 2.2.22 JBOSS-EAP-6

What mechanism/configuration do I need to use in server1 to make it possible? Please see if someone can help with this.

Answer 1

Well, you just add a ProxyPass setting. mod_cluster is compatible with ProxyPass, so you can use both.

For instance, if I would like gif images to be served by httpd, not by AS7, I can add:

ProxyPassMatch ^(/.*\.gif)$ !  

Furthermore, if you set

CreateBalancers 1

mod_cluster won't create proxies for you and you have to do it yourself. This gives you an additional control. For instance:

ProxyPassMatch ^/static/ !
ProxyPass / balancer://qacluster stickysession=JSESSIONID|jsessionid nofailover=on
ProxyPassReverse / balancer://qacluster
ProxyPreserveHost on

In the aforementioned example, we proxy anything but /static/ content to the workers.

• Note:If you encounter any cookies related issues, you might want to play with ProxyPassReverseCookieDomain and ProxyPassReverseCookiePath.

• Note qacluster in my config. The default is mycluster , so for naming my balancer qacluster, I added this to mod_cluster config (outside VirtualHost):

   ManagerBalancerName qacluster 

If it is not clear, just reply and I can try to elaborate further.

Answer 2

I had the same issue where in we were using Apache HTTP server for static content and JBOSS AS 7 server for dynamic contents (the JSF web app).

So adding the below property at the end of Load modules tells

CreateBalancers 0   

Tells to "0: Create in all VirtualHosts defined in httpd."

More at: http://docs.jboss.org/mod_cluster/1.2.0/html/native.config.html#d0e485

And the below config solved the issues of images and styel sheets not getting displayed.

<VirtualHost *:80>
  ServerName dev.rama.com
  DocumentRoot "/var/www/assests"
  UseAlias 1
  ProxyPassMatch ^(.*\.bmp)$ !
  ProxyPassMatch ^(.*\.css)$ !
  ProxyPassMatch ^(.*\.gif)$ !
  ProxyPassMatch ^(.*\.jpg)$ !
  ProxyPassMatch ^(.*\.js)$ !
  ProxyPassMatch ^(.*\.png)$ !
 <Directory /var/www/assests>
   Options Indexes FollowSymLinks
   AllowOverride None
   Order allow,deny
   Allow from all
 </Directory>

Note: All our assests for the web app was on HTTP server at /var/www/assests and the url I was accessing was dev.rama.com on port 80

So when it sees this ProxyPassMatch ^(.*.css)$ ! The webserver knows that the css files are local to the http server and we dont need to go to Jboss App server.

More info at http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass