Installation guide

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Verify that the defined alias corresponds to a worker node's server name.
LBstat usRe calT ime
Defines the interval in seconds between the proxy calculating the status of a worker node. T he
default interval is 5 seconds.
ProxyPa ssMatch; ProxyPass
ProxyPass maps remote servers into the local server namespace. If the local server has an
address http://local.com/, then the following ProxyPass directive would convert a local
request for http://local.com/requested/file1 into a proxy request for
http://worker.local.com/file1.
ProxyPass /requested/ http://worker.local.com/
ProxyPassMatch uses Regular Expressions to match local paths to which the proxied URL
should apply.
For either directive, ! indicates that a specified path is local, and a request for that path should
not be routed to a remote server. For example, the following directive specifies that .gif files
should be served locally.
ProxyPassMatch ^(/.*\.gif)$ !
6.1.3. mod_adve rtise.so
The Proxy Advertisement module, mod_advertise.so, broadcasts the existence of the proxy server via
UDP multicast messages. T he server advertisement messages contain the IP address and port number
where the proxy is listening for responses from nodes that wish to join the load-balancing cluster.
This module must be defined alongside mod_manager in the VirtualHost element. Its identifier in the
following code snippet is advertise_module.
LoadModule advertise_module modules/mod_advertise.so
mod_advertise also takes the following directives:
ServerAdvertise
Defines how the advertising mechanism is used.
When set to On, the advertising mechanism is used to tell worker nodes to send status
information to this proxy. You can also specify a hostname and port with the following syntax:
ServerAdvertise On http://hostname:port/. This is only required when using a name-
based virtual host, or when a virtual host is not defined.
The default value is On. When set to off, the proxy does not advertise its location.
Advert iseGroup
Defines the multicast address to advertise on. The syntax is AdvertiseGroup address:port,
where address should correspond to AdvertiseGroupAddress , and port should
correspond to AdvertisePort in your worker nodes.
If your worker node is JBoss Enterprise Application Platform-based, and the -u switch is used
at startup, the default AdvertiseGroupAddress is the value passed via the -u switch.
The default value is 224.0.1.105:23364. If port is not specified, the default port used is
23364.
Advert iseFrequency
The interval (in seconds) between multicast messages advertising the IP address and port.
The default value is 10.
Advert iseSecurityKey
Defines a string used to identify the JBoss HTT P Connector mod_cluster in JBoss Web. By
default this directive is not set and no information is sent.
26 Chapter 6. Install proxy server components