About types of discovery

Discovery and rediscovery

Discovery

The term discovery is used generally to mean any kind of discovery. Technically, only the first discovery that is run after the discovery engine, ncp_disco, is started can properly be called a discovery, and every discovery after that is a rediscovery. Because there is no discovery data in memory yet, discoveries take slightly longer than rediscoveries.

Rediscovery

After a discovery has been run, any further discoveries that are run are rediscoveries. Rediscoveries use a different data flow to discoveries, with some different stitchers and database tables. If ncp_disco is restarted, the next discovery is again just a discovery, and further discoveries after that are rediscoveries. Unless you are running advanced discoveries or modifying the discovery data flow, the difference between a discovery and a rediscovery is not usually important, and, for ease of reading, the instructions in this information do not distinguish between discovery and rediscovery unless it is necessary.

Full and partial discovery

Full discovery

A full discovery is a discovery run with a large scope, intended to discover all of the network devices that you want to manage. Full discoveries are usually just called discoveries, unless they are being contrasted with partial discoveries.

Partial discovery

A partial discovery is a subsequent rediscovery of a section of the previously discovered network. The section of the network is usually defined using a discovery scope consisting of either an address range, a single device, or a group of devices. A partial discovery relies on the results of the last full discovery, and can only be run if the discovery engine, the ncp_disco process, has not been stopped since the last full discovery. A partial discovery is, therefore, actually a type of rediscovery.

Scheduled discovery

You can schedule a full discovery to start at a certain time. For example, you can schedule a full discovery to run at the same time every night, or at the same time on the same day every week, or at the same time every day of the month.

Queued discovery

You can queue discoveries for different domains. When the discovery for one domain finishes, the discovery for the next domain in the queue is triggered. Only full discoveries can be queued.