FibroLAN Falcon Gen-3 M-Class, User Manual

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Falcon M-Class | User Guide
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Table 4-75: System and Port Configuration Parameters
1.
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
Age 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.
The table has one row for each port on the selected switch and a number of columns.
2.
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 (refer to next page).
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.