Database File Format - 3Com 3C15500 - Network Director User Manual

396 C 9: P
HAPTER ERFORMANCE

Database file format

R
EPORTING
If you do not know the MAC address, or the device in question has
multiple MAC addresses, you can find the device on the 3Com Network
Director map using the Edit > Find dialog box, and launch its Properties
dialog box. The MAC address used by 3Com Network Director for
historical data logging will be the first MAC address listed in this dialog
box.
Links are handled differently depending on the end type. If the link is
between two switches or hubs, then the link is identified based solely on
the devices' MAC addresses. So if the link changes, or ports or links are
added to an aggregated link, any existing logged data is retained.
A link between a switch or hub and an end station or cloud is handled
differently. The link is identified based on the MAC address of the switch
or hub, and on the unit and port that the link is connected to on that
switch or hub. This means if the end station is swapped out, and replaced
with a different end station, the data is retained.
This is illustrated in the following scenarios:
An end station connected to a switch is replaced with another end
station and connected to the same port.
Data for the link is retained
Data for the new end station starts from scratch
A switch is hot-swapped and connected up in the same fashion as the old
switch.
Data for all links starts from scratch
Data for the new switch starts from scratch
A core link between two switches is moved from one port to another.
Data for the connection between the two switches is retained.
Data gathered by 3Com Network Director is held in RRDTool round robin
databases. See "Database"
These files may be accessed directly via the RRDTool utility, which is
located in the directory:
on page 391 for further details.