This section describes load balancing via Apache + mod_jk and Apache + mod_cluster.
Describe load balancing with Apache using mod_jk.
Describe load balancing with Apache using mod_cluster.
The mod_cluster integration is done via the modcluster subsystem it requires mod_cluster-1.1.x.or mod_cluster-1.2.x (since 7.1.0)
The modcluster subsystem supports several operations:The operations specific to the modcluster subsystem are divided in 3 categories the ones that affects the configuration and require a restart of the subsystem, the one that just modify the behaviour temporarily and the ones that display information from the httpd part.
There are 2 operations that display how Apache httpd sees the node:
Send a DUMP message to all Apache httpd the node is connected to and display the message received from Apache httpd.
Send a INFO message to all Apache httpd the node is connected to and display the message received from Apache httpd.
there are 3 operation that could be used to manipulate the list of Apache httpd the node is connected too.
Displays the httpd that are connected to the node. The httpd could be discovered via the Advertise protocol or via the proxy-list attribute.
Remove a proxy from the discovered proxies or temporarily from the proxy-list attribute.
Add a proxy to the discovered proxies or temporarily to the proxy-list attribute.
Those operations allow to send context related commands to Apache httpd. They are send automatically when deploying or undeploying webapps.
Tell Apache httpd that the context is ready receive requests.
Tell Apache httpd that it shouldn't send new session requests to the context of the virtualhost.
Tell Apache httpd that it shouldn't send requests to the context of the virtualhost.
Those operations are like the context operation but they apply to all webapps running on the node and operation that affect the whole node.
Refresh the node by sending a new CONFIG message to Apache httpd.
reset the connection between Apache httpd and the node
There are 4 metric operations corresponding to add and remove load metrics to the dynamic-load-provider. Note that when nothing is defined a simple-load-provider is use with a fixed load factor of one.
that corresponds to the following configuration:
Add a metric to the dynamic-load-provider, the dynamic-load-provider in configuration is created if needed.
Remove a metric from the dynamic-load-provider.
like the add-metric and remove-metric except they require a class parameter instead the type. Usually they needed additional properties which can be specified
which corresponds the following in the xml configuration file:
If you want to use your own JVM route instead of automatically generated one you can insert the following property: