Bpdu Cop - Allied Telesis SwitchBlade x3100 Series Manual

BPDU COP

Introduction
4.5.10 BPDU COP
4.5.10.1 Overview
An SBx3112 interface could be connected to some other device (i.e.a switch), in which a network loop was implemented. To
prevent the network loop from affecting the entire network when the SBx3112 BPDU Cop enabled interface receives a
BPDU that interface will be temporarily or permanently disabled depending on how the interface is configured
This is prevented with a feature called BPDU Cop. The parameter BPDUCOP={ ON | OFF } is part of the SET STP
INTERFACE command and is set against the specific interface(s).
There is a second parameter (TIMEOUT=0..2048), that when set to a non-zero value determines how many minutes the
system will wait before it tries to re-enable the interface.
4.5.10.2 Feature without AutoRecovery (TIMEOUT=0)
When a BPDU is received and the feature is activated, the operational state goes to DOWN and the state changes to
AUTO-DISABLED, as shown in 4.5.11.
Note that once the interface is set to AutoDisabled by the system, the user must disable and enable the inter-
face to clear the alarm and bring the interface back into service. In other words, once an interface is placed
out of service by the BPDU Cop feature, it will stay disabled unless it is explicitly brought back up
by the user.
4.5.10.3 Feature with Auto Recovery (TIMEOUT=1 to 2048, Default = 10)
With the TIMEOUT parameter, the Auto-Recovery is activated, and this allows the option to have the system
wait 1 to 2048 minutes before automatically re-enabling the interface.
When BPDU Cop is enabled, the auto recovery is also enabled by default, with TIMEOUT set at 10 minutes.
4.5.10.4 Summary of Feature Operation
Table 4-14 shows the state of the interface, how the parameters can be set, and how the feature will work.
Included in the table are possible (although uncommon) situations where the user may change a parameter
while the interface is in a failed state.
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Software Reference for SwitchBlade x3100 Series Switches (Layer Two Switching)