Tornado

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Overview
Tornado Target Server
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The target server runs on the host, and connects the Tornado tools to the target
agent. There is one server for each target; all host tools access the target through
this server, whose function is to satisfy the tool requests by breaking each request
into the necessary transactions with the target agent. The target server manages the
details of whatever connection method to the target is required, so that each tool
need not be concerned with host-to-target transport mechanisms.
In some cases, the server passes a tool’s service request directly to the target agent.
In other cases, requests can be fulfilled entirely within the target server on the host.
For example, when a target-memory read hits a memory region already cached in
the target server, no actual host-to-target transaction is needed.
The target server also allocates target memory from a pool dedicated to the host
tools, and manages the target’s symbol table on the host. This permits the server to
do most of the work of dynamic linking—address resolution—on the host system,
before downloading a new module to the target.
A target server need not be on the same host as the Tornado tools, as long as the
tools have network access to the host where the target server is running.
Target servers can be started from the Tornado launcher or from the UNIX
command line (or scripts). See 2.7 Connecting a Tornado Target Server, p.54 for a
discussion of starting a server from the UNIX command line, and see 3.5 Managing
Target Servers, p.72 for details on using graphical facilities in the launcher. For
reference information on target servers, see the tgtsvr entry in D. Tornado Tools
Reference.
Tornado Registry
Tornado provides a central target server registry that allows you to select a target
server by a convenient name. The registry associates a target server’s name with
the network address needed to connect with that target server. You can see the
registry indirectly through the list of available targets. The Tornado registry need
not run on the same host as your tools, as long as it is accessible on the network.
To help keep server names unique over a network of interacting hosts, targetserver
names have the form targetName@host, where targetName is a target-server
name selected by the user who launches a server (with the network name of the
target as a default). The registry rejects registration attempts for names that are
already in use.
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