Intellinet 560931, Руководство пользователя

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System Configuration
Mode
Indicates if Limit Control is globally enabled or disabled on the switch. If globally 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 Period 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 third-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 weren't for aging, the end-host would still take up resources on
this switch and would 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 up on the switch.
Port Configuration
The table allows you to configure the Port Configuration parameters:
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 will be sent every time the limit gets
exceeded.