User manual

C HAPTER 4 | Configuring the Switch
Configuring Security
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◆ 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 “initialized” 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 the specified Limit of 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 is
exceeded.
■
Shutdown: If Limit + 1 MAC addresses is seen on the port, shut
down the port. This implies that all secured MAC addresses will be
removed from the port, and no new addresses will be learned. Even
if the link is physically disconnected and reconnected on the port
(by disconnecting the cable), the port will remain shut down. There
are three ways to re-open the port:
■
Boot the switch,
■
Disable and re-enable Limit Control on the port or the switch,
■
Click the Reopen button.
■
Trap & Shutdown: If Limit + 1 MAC addresses is seen on the port,
both the “Trap” and the “Shutdown” actions described above will be
taken.
◆ State – This column shows the current state of the port as seen from
the Limit Control's point of view. The state takes one of four values:
■
Disabled: Limit Control is either globally disabled or disabled on the
port.
■
Ready: The limit is not yet reached. This can be shown for all
Actions.
■
Limit Reached: Indicates that the limit is reached on this port. This
state can only be shown if Action is set to None or Trap.
■
Shutdown: Indicates that the port is shut down by the Limit Control
module. This state can only be shown if Action is set to Shutdown or
Trap & Shutdown.
◆ Re-open – If a port is shut down by this module, you may reopen it by
clicking this button, which will only be enabled if this is the case. For
other methods, refer to Shutdown in the Action section.
Note, that clicking the Reopen button causes the page to be refreshed,
so non-committed changes will be lost.