On startup, the discovery engine, ncp_disco, populates
the agent and stitcher databases with information extracted from the
discovery agent and discovery stitcher files. While operating, ncp_disco
scans for alterations to the agent and stitcher files and updates
the agent and stitcher databases if necessary. The frequency of scans
is set in the disco database.
The agents and stitchers databases contain definition and
configuration information for the agents and stitchers, such as a
list of the types of devices that are sent to any given agent. The
information in these databases is extracted by the discovery engine
from the following directories:
- /precision/disco/agents
- /precision/disco/stitchers
The stitchers databases also contain information about when any
given stitcher is triggered; for example, "start stitcher X upon completion
of agent Y," or "start stitcher X upon the insertion of an entry into
database table Z." It is therefore possible to start stitchers on
demand by inserting their name into the appropriate actions table
using OQL. The necessary agents are started automatically when a device
is inserted into the despatch table of the agent.