Dell Force10 S4810P, Справочное руководство

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portfast
[bpduguard
[shutdown-on-
viol ation]]
Enter the keyword
portfast
to enable Portfast to move the
interface into Forwarding mode immediately after the root fails.
Enter the optional keyword
bpduguard
to disable the port when it
receives a BPDU.
Enter the optional keyword
shutdown-on-violation
to
hardware disable an interface when a BPDU is received and the port
is disabled.
priority
priority
Enter keyword
priority
followed by a number as the priority. The
range is zero (0) to 15. The default is 8.
Defaults cost = depends on the interface type; priority = 8
Command Modes INTERFACE
Command History
Version 8.3.11.1 Introduced on the Z9000.
Version 8.3.10.1 Introduced the
loopguard
and
rootguard
options on the S4810.
Version 8.4.2.1 Introduced the
loopguard
and
rootguard
options on the E-
Series TeraScale, C-Series, and S-Series.
Version 8.3.7.0 Introduced on the S4810.
Version 8.2.1.0 Introduced the
shutdown-on-violation
option.
Version 7.7.1.0 Introduced on the S-Series.
Version 7.5.1.0 Introduced on the C-Series.
Version 6.2.1.1 Introduced on the E-Series.
Usage
Information
If you enable
portfast bpduguard
on an interface and the interface receives a BPDU,
the software disables the interface and sends a message stating that fact. The port is in
ERR_DISABLE mode, yet appears in the
show interface
commands as enabled. If you do
not enable
shutdown-on-violation
, BPDUs still are sent to the RPM CPU.
STP loop guard and root guard are supported on a port or port-channel enabled in any
Spanning Tree mode: Spanning Tree Protocol (STP), Rapid Spanning Tree Protocol (RSTP),
Multiple Spanning Tree Protocol (MSTP), and Per-VLAN Spanning Tree Plus (PVST+).
Root guard is supported on any STP-enabled port or port-channel except when used as a
stacking port. When enabled on a port, root guard applies to all VLANs configured on the port.
STP root guard and loop guard cannot be enabled at the same time on a port. For example, if
you configure loop guard on a port on which root guard is already configured, the following
error message is displayed:
% Error: RootGuard is configured. Cannot
configure LoopGuard
.
Do not enable Portfast BPDU guard and loop guard at the same time on a port. Enabling both
features may result in a port that remains in a blocking state and prevents traffic from flowing
through it. For example, when Portfast BPDU guard and loop guard are both configured:
• If a BPDU is received from a remote device, BPDU guard places the port in an Err-
Disabled Blocking state and no traffic is forwarded on the port.
• If no BPDU is received from a remote device, loop guard places the port in a Loop-
Inconsistent Blocking state and no traffic is forwarded on the port.
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