ECIS4500 series Web Management Guide R02

Command Descriptions
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disabled, other modules may still use the underlying functionality, but limit checks and
corresponding actions are disabled.
Aging Enabled
If checked, secured MAC addresses are subject to aging as discussed under Aging
Period .
Aging Period
If Aging Enabled is checked, then the aging period is controlled with this input. If other
modules are using the underlying port security for securing MAC addresses, they may
have other requirements to the aging period. The underlying port security will use the
shorter requested aging period of all modules that use the functionality.
The Aging Period can be set to a number between 10 and 10,000,000 seconds.
To understand why aging may be desired, consider the following scenario: Suppose
an end-host is connected to a 3rd party switch or hub, which in turn is connected to a
port on this switch on which Limit Control is enabled. The end-host will be allowed to
forward if the limit is not exceeded. Now suppose that the end-host logs off or powers
down. If it wasn't for aging, the end-host would still take up resources on this switch
and will be allowed to forward. To overcome this situation, enable aging. With aging
enabled, a timer is started once the end-host gets secured. When the timer expires,
the switch starts looking for frames from the end-host, and if such frames are not seen
within the next Aging Period, the end-host is assumed to be disconnected, and the
corresponding resources are freed on the switch.
Port Configuration
Port
The port number to which the configuration below applies.
Mode
Controls whether Limit Control is enabled on this port. Both this and the Global Mode
must be set to Enabled for Limit Control to be in effect. Notice that other modules may
still use the underlying port security features without enabling Limit Control on a given
port.
Limit
The maximum number of MAC addresses that can be secured on this port. This
number cannot exceed 1024. If the limit is exceeded, the corresponding action is
taken.
The switch is "born" with a total number of MAC addresses from which all ports draw
whenever a new MAC address is seen on a Port Security-enabled port. Since all ports
draw from the same pool, it may happen that a configured maximum cannot be
granted, if the remaining ports have already used all available MAC addresses.
Action
If Limit is reached, the switch can take one of the following actions:
None: Do not allow more than Limit MAC addresses on the port, but take no further
action.
Trap: If Limit + 1 MAC addresses is seen on the port, send an SNMP trap. If Aging is
disabled, only one SNMP trap will be sent, but with Aging enabled, new SNMP traps