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AppLogic 2.3 Beta Documentation The latest production release is AppLogic 2.4.7

RPL: Event Replicator

Latest Version: 1.1.2

	At a Glance
	Catalog	System
	Category	Switches
	User volumes	no
	Min. memory	64M
	OS	Linux
	Constraints	no
	Questions/Comments	Ask Forum

RPL is a replicator for events. It replicates HTTP requests received on its input terminal to all its output terminals.

RPL sends any headers and documents received with the request to the outputs. RPL ignores the responses from the output requests, including possible failures to send the request. RPL always returns SUCCESS for recognized HTTP requests on its input, without waiting for any of the outputs to respond. For requests that require a document to be returned, RPL returns an empty document.

RPL is intended for distributing fire-and-forget asynchronous notifications. (Future versions of RPL may have additional parameterization that modifies its behavior, including aggregating the responses from outputs and returning them on the input).

RPL can tolerate, and indeed expects under normal circumstances, any of its outputs being unconnected or non-responsive. Appliances connected to RPL's outputs may be stopped, on standby or non-responsive, without this affecting the operation and performance of RPL.

RPL can be cascaded by connecting other RPL instances to one or more of RPL's outputs.

Boundary

Resources

Resource	Minimum	Maximum	Default
CPU	0.05	4	0.05
Memory	64 MB	128 MB	64 MB
Bandwidth	1 Mbps	1 Gbps	1 Mbps

Note: the amount of memory given to the appliance does not affect its throughput or performance significantly. The memory only controls the amount of request data that can be concurrently submitted through RPL.

Terminals

name	dir	prot.	description
`in`	in	`http`	Request input. HTTP requests received on this input are replicated and sent to all of the connected RPL outputs. RPL completes the request with success and, where appropriate, returns an empty document, regardless of the results of forwarded requests and without waiting for any responses from the outputs.
`out1-out8`	out	`http`	Replication outputs. Requests received on the input terminal are replicated to each of the connected outputs; the results are ignored. Any and all of these outputs can be left unconnected; any of the outputs may be connected to appliances that are not started and/or non-responsive.
`mon`	out	`cce`	Sends performance and resource usage statistics. This terminal may be left unconnected if it is not used.