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DGS-3400 Series Layer 2 Gigabit Managed Switch CLI Manual
96
config fdb aging_time
Purpose
Used to set the aging time of the forwarding database.
Syntax
config fdb aging_time <sec 10–1000000>
Description
The aging time affects the learning process of the Switch. Dynamic forwarding table
entries, which are made up of the source MAC addresses and their associated port
numbers, are deleted from the table if they are not accessed within the aging time. The
aging time can be from 10 to 1000000 seconds with a default value of 300 seconds. A
very long aging time can result in dynamic forwarding table entries that are out–of–date
or no longer exist. This may cause incorrect packet forwarding decisions by the Switch. If
the aging time is too short however, many entries may be aged out too soon. This will
result in a high percentage of received packets whose source addresses cannot be found
in the forwarding table, in which case the Switch will broadcast the packet to all ports,
negating many of the benefits of having a switch.
Parameters
<sec 10–1000000>
−
The aging time for the MAC address forwarding database value.
The value in seconds may be between 10 and 1000000 seconds.
Restrictions
Only Administrator and Operator-level users can issue this command.
Example usage:
To set the FDB aging time:
D G S – 3 4 2 6 : 5 # c o n f i g f d b a g i n g _ t i m e 3 0 0
C o m m a n d : c o n f i g f d b a g i n g _ t i m e 3 0 0
S u c c e s s .
D G S – 3 4 2 6 : 5 #
delete fdb
Purpose
Used to delete an entry to the Switch’s forwarding database.
Syntax
delete fdb <vlan_name 32> <macaddr>
Description
This command is used to delete a previous entry to the Switch’s MAC address forwarding
database.
Parameters
<vlan_name 32>
−
The name of the VLAN on which the MAC address resides.
<macaddr>
−
The MAC address that will be deleted from the forwarding table.
Restrictions
Only Administrator and Operator-level users can issue this command.
Example usage:
To delete a permanent FDB entry:
D G S – 3 4 2 6 : 5 # d e l e t e f d b d e f a u l t 0 0 – 0 0 – 0 0 – 0 0 – 0 1 – 0 2
C o m m a n d : d e l e t e f d b d e f a u l t 0 0 – 0 0 – 0 0 – 0 0 – 0 1 – 0 2
S u c c e s s .
D G S – 3 4 2 6 : 5 #
Example usage:
To delete a multicast FDB entry:
