HP Network Direr Software Products manual Key Concepts

Key Concepts 105

Once 3Com Network Director completes its additional discovery it then updates the main database (and subsequently the map) with the newly discovered information. It does this by comparing the information that exists in the main database with that in the new, temporary database. The basic rules it applies, when updating the main database, are as follows:

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Any new subnets are simply added to the new database as they would be on an initial discovery

Any new devices are simply added to the appropriate subnets (either existing or new).

Any devices that have changed (e.g. unit added/removed) are updated

– you can view their new details using the Properties dialog box.

Devices that exist in the main database but have been removed from the network and/or simply did not respond in the second discovery will not be deleted from the database or the map. The exception to this is if a device’s IP address now belongs to another device. For example: device A initially has address x, device B has address y. On a subsequent discovery device A now has both addresses x and y. In this scenario device A’s information will be updated to reflect its new addresses and device B will be deleted.

■Any new links (that is, connections between devices and/or device’s ports) detected by the topology process will be added to the relevant devices on the map.

■If a port previously had a link to a device and that port is subsequently detected as being connected to a different device, the old link will be deleted and the new one created. A port can only be connected to one other node.

■If a port previously had a link and the second discovery could not successfully establish that the same port was connected (for example, 3Com Network Director lost communication part way through) then that link will not be deleted. Instead it will be marked as unconfirmed and as a result will appear as a dashed line on the map.

Any changes detected as a result of additional discoveries are fully described in the Changes report, automatically generated by 3Com Network Director at the end of a rediscovery operation. See “The Changes Report” on page 133.