Dell PowerSwitch S5212F-ON OS10 Enterprise Edition User Guide Release 10.4.3.0 - Page 343
Loop guard, Global parameters
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Configured hello time 2, max age 20, forward delay 15 Interface Designated Name PortID Prio Cost Sts Cost Bridge ID PortID ethernet1/1/5 128.276 128 500 FWD 0 24577 90b1.1cf4.a523 128.276 ethernet1/1/6 128.280 128 500 LRN 0 24577 90b1.1cf4.a523 128.280 Interface Name Role PortID Prio Cost Sts Cost Link-type Edge ethernet1/1/5 Desg 128.276 128 500 FWD 0 AUTO No ethernet1/1/6 Desg 128.280 128 500 LRN 0 AUTO No Loop guard To configure loop guard on an interface: • Enable loop guard on a per-port or port-channel interface in INTERFACE mode. spanning-tree guard {loop | root | none} - loop - Enables loop guard on an interface. - root - Enables root on an interface. - none - Enables the guard mode to none. • Disable loop guard on a port or port-channel interface in INTERFACE mode. no spanning-tree guard loop Port enabled with loop guard conditions • Loop guard is supported on any STP-enabled port or port-channel interface in RPVST+ mode. • You cannot enable root guard and loop guard at the same time on an STP port. The loop guard configuration overwrites an existing root guard configuration and vice versa. • Enabling BPDU guard and loop guard at the same time on a port results in a port that remains in the Blocking state and prevents traffic from flowing through it. For example, when you configure both Portfast BPDU guard and loop guard: - If a BPDU is received from a remote device, BPDU guard places the port in the Err-Disabled Blocking state and no traffic forwards on the port. - If no BPDU is received from a remote device which was sending BPDUs, loop guard places the port in the Loop-Inconsistent Blocking state and no traffic forwards on the port. • When used in a PVST+ network, STP loop guard performs per-port or per port-channel at a VLAN level. If no BPDUs are received on a port-channel interface, the port or port-channel transitions to a Loop-Inconsistent or Blocking state only for this VLAN. Global parameters All non-root bridges accept the timer values on the root bridge. Forward-time Hello-time Max-age Amount of time required for an interface to transition from the Discarding state to the Learning state or from the Learning state to the Forwarding state. Time interval within which the bridge sends BPDUs. Length of time the bridge maintains configuration information before it refreshes information by recomputing the RPVST+ topology. • Modify the forward-time in seconds in CONFIGURATION mode, from 4 to 30, default 15. spanning-tree vlan vlan-id forward-time seconds • Modify the hello-time in seconds in CONFIGURATION mode, from 1 to 10, default 2. With large configurations involving more numbers of ports, Dell EMC recommends increasing the hello-time. spanning-tree vlan vlan-id hello-time seconds Layer 2 343
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1,162
-
1,163
-
1,164
-
1,165
-
1,166
-
1,167
-
1,168
-
1,169
-
1,170
-
1,171
-
1,172
-
1,173
-
1,174
-
1,175
-
1,176
-
1,177
-
1,178
-
1,179
-
1,180
-
1,181
-
1,182
-
1,183
-
1,184
-
1,185
-
1,186
-
1,187
-
1,188
-
1,189
-
1,190
-
1,191
-
1,192
-
1,193
-
1,194
-
1,195
-
1,196
-
1,197
-
1,198
-
1,199
-
1,200
-
1,201
-
1,202
-
1,203