Guralp Systems CD1.1 - Manual (Page 21)

Operator's Guide
4 Using the Multiplexor
The multiplexor module has two main functions: Firstly, it acts
as an IPC connection point between the input and output
modules, allowing an arbitrary number of modules of either
type to be connected together; Secondly, it stores subframes
on disk, allowing them to be retrieved by output modules for
back-fill and retransmission purposes.
In most applications, only a single multiplexor instance is
required although, if you have two completely independent
data paths, it may make sense to use more than one
multiplexor. Note that each input and/or output module can
only ever be connected to a single multiplexor instance.
4.1 Creating a new multiplexor instance
In the web interface, select “Configuration -> Services” from
the left-hand menu or from the command line, run
gconfig
and then select “System services”.
Now choose “data-mux-cd11 -- CD1.1 multiplexor” to view a list
of configured multiplexor instances. You can choose to either
configure any existing instance (as described in the following
section) or select “Create new service instance” to create a
new one.
A form is displayed which allows you to set various parameters
for the instance. The default values are suitable for most
applications but each parameter is discussed in the following
section. After entering the desired configuration for the
instance, choose Submit.
This will create (if it is new) and configure the multiplexor
instance. If it is not already running, you can start it by using
“Control -> Services” on the web menu or by running
/etc/init.local/data-mux-cd11.0 start
from the command line.
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