ZyXEL Communications RGS Series User Manual page 77

Port Configuration
Port
Mode
Limit
Action
State
Re-open Button
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 port number to which the configuration below applies.
Controls whether Limit Control is enabled on this port. Both this and the
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.
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
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.
If Limit is reached, the switch can take one of the following actions:
None: Do not allow more than
action.
Trap: If Limit + 1 MAC addresses are 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.
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
address 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:
1) Boot the switch,
2) Disable and re-enable Limit Control on the port or the switch,
3) Click the Reopen button.
Trap & Shutdown: If Limit
and the "Shutdown" actions described above will be taken.
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
If a port is shutdown 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.
Limit MAC addresses on the port, but take no further
+ 1 MAC addresses is seen on the port, both the "Trap"
Action is set to Shutdown or Trap & Shutdown.
Global Mode
action is
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