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The Node
The LabRAD Node is a server that is used for starting and stopping other servers.
There are three files that are relevant to the node:
Each of these is documented (in the module docstring, at least) with their relevant purposes and requirements (including e.g. registry keys).
The node is currently implemented as a Twisted plugin. As long as twisted.plugins.labrad_node is in your pythonpath, you can run the plugin like this:
twistd -n labradnode
where -n means "don't daemonize" and labradnode is the name of the plugin. (Note that either installing pylabrad with setup.py or putting the labrad/ folder in your pythonpath is sufficient.) Running the node as a plugin is handy because if you restart the manager, it will automatically attempt to reconnect.
There is also a new script in the scripts folder of pylabrad, labradnode.py. All this does is the equivalent of the twistd command given earlier. This makes it easy to start the node without a command line (e.g. in Windows).
Each node has a name--either the environment variable LABRADNODE or the system's hostname.
You must point the node to the folder where your servers are stored. There is a folder in the registry for the node, >> Nodes >> [node name], with the key "Directories", which is a list of directories (strings) that the node looks to for servers. (This registry directory may be created automatically when the node is first run with a given node name.)
The node is fairly self-explanatory to use; key settings are available_servers, running_servers, start, stop, status, etc.
Note that if you change the node such that there's a syntax error (i.e. so that the file errors on import) then the plugin will not show up in the list of twisted plugins (from twistd --help). You can check for import errors by simply doing import labrad.node.
The twisted plugin docs are here.