User's Manual

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egress means to exert an influence on the
egress.
exit Backs to the global configuration mode.
exit Backs to the EXEC mode.
25.5 Loopback Detection
Loopback detection is used to check whether loopback exists on an interface. You can configure the
interval for a port to transmit the loop check packets. Run the following command in EXEC mode to forward
the time interval of the loopback detection packets.
Command Purpose
config Enters the global configuration mode.
Interface g0/1 Enters the to-be-configured port.
[no] keepalive [second]
To configure the interval for a port to transmit
the loop check packets, run keepalive second.
second means the interval of transmitting the
packets.
exit Backs to the global configuration mode.
exit Backs to the EXEC mode.
25.6 MAC Address Learning
To enable or disable MAC learning on a port, run the following commands.
Command Purpose
config Enters the global configuration mode.
interface g0/1 Enters the to-be-configured port.
[no] switchport disable-learning
Configures MAC Learning on a Port.
Enable/disable port MAC address learning.
exit Backs to the global configuration mode.
exit Backs to the EXEC mode.
25.7 Port Security
Port security supports security control on an interface. Port security has three modes: dynamic security
mode, static reception mode and static rejection mode. In dynamic security mode, you can set the threshold
of MAC addresses that can be learned by a port. If the learned MAC addresses on a port have reached the
threshold in number, the switch will not learn the MAC addresses any more and at the same time drop all DLF