Cabletron Systems NB30, Руководство пользователя

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USING BRIDGE MANAGEMENT OPTIONS
5-26
CRC Errors:
Indicates the number of packets detected with Cyclical Redundancy
Check (CRC) failures.
Frame Alignment Errors:
Indicates the number of errors due to misaligned packets.
After you have examined all pertinent counter data, you can return to the
Bridge Counters Screen to select another option by highlighting
RETURN and pressing the Return key.
5.4 THE FILTERING DATABASE OPTION
The Filtering Database is composed of three databases: the Permanent
Database, the Acquired Database, and the Special Filtering Database. The
Permanent and Acquired databases make up the Source Address Table.
The Special Database allows you to create additional filters to screen
frames passing through the bridge. See Figure 5-9.
The Permanent Database
This contains addresses that remain in the Source Address Table when the
system is shut down. With Local Management for the NB30, the network
manager can add to or delete from this database.
The Acquired Database
This consists of address entries that accumulate as part of the Filtering
Database while the bridge is up and running. The Acquired Database also
contains the addresses that are in the Permanent Database upon startup of
the bridge. The entries that accumulate in this database are not saved
when the system is shut down. Entries to this database are one of two
types: Static or Dynamic.
Dynamic entries are addresses that are added to the Acquired Database
through the bridge's learning process. Static entries are addresses that the
network manager adds to the Acquired Database. The network manager
can also delete both static and dynamic entries from the Acquired
Database.