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Table Of Contents
Clusters
When a client sends batches to the Apple Qmaster distributed processing system, all the
processing and subsequent moving of any output files is performed by a group of
Apple Qmaster–configured computers called a cluster. You can create one or more clusters
of service nodes, with one cluster controller included in each cluster. Each computer in
the cluster is connected to the other computers in the cluster through a network
connection.
Cluster
controller
Service
node
Service
node
Service
node
Example of a cluster
Note: This illustration provides only one simple example of a cluster. Other possibilities
are described in Examples of a Distributed Processing Network.
Service Nodes
The service nodes are where the processing work is done. When you assign a group of
service nodes to a cluster, they function as one very powerful computer because all their
resources are shared. If one service node is overloaded or otherwise inaccessible, another
service node is used.
You make a computer available as a service node by configuring it in the Apple Qmaster
Sharing window, accessible from Compressor by choosing Share This Computer from the
Apple Qmaster menu.
The Minimum You Need to Know
The following are the basic rules for setting up a distributed processing network:
A cluster must contain one (and only one) computer acting as the cluster controller,
and at least one computer acting as the service node. (These two can be the same
computer, as shown in Using One Computer to Serve Two Distributed Processing Roles.)
The client computers and the computers in any cluster that supports them must be
on the same network.
The network must support the Apple networking technology built in to Mac OS X.
All the computers in a cluster need read-and-write access to any computers (or storage
devices) that will be specified as output destinations for files.
353Chapter 29 Apple Qmaster and Distributed Processing