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C
HAPTER
36
| Spanning Tree Commands
– 759 –
Where more than one port is assigned the highest priority, the port with
lowest numeric identifier will be enabled.
E
XAMPLE
Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree port-priority 0
R
ELATED
C
OMMANDS
spanning-tree root-
guard
This command prevents a designated port
22
from taking superior BPDUs
into account and allowing a new STP root port to be elected. Use the
no
form to disable this feature.
S
YNTAX
[
no
]
spanning-tree
root-guard
D
EFAULT
S
ETTING
Disabled
C
OMMAND
M
ODE
Interface Configuration (Ethernet, Port Channel)
C
OMMAND
U
SAGE
A bridge with a lower bridge identifier (or same identifier and lower
MAC address) can take over as the root bridge at any time.
When Root Guard is enabled, and the switch receives a superior BPDU
on this port, it is set to the Discarding state until it stops receiving
superior BPDUs for a fixed recovery period. While in the discarding
state, no traffic is forwarded across the port.
Root Guard can be used to ensure that the root bridge is not formed at
a suboptimal location. Root Guard should be enabled on any designated
port connected to low-speed bridges which could potentially overload a
slower link by taking over as the root port and forming a new spanning
tree topology. It could also be used to form a border around part of the
network where the root bridge is allowed.
When spanning tree is initialized globally on the switch or on an
interface, the switch will wait for 20 seconds to ensure that the
spanning tree has converged before enabling Root Guard.
22. See Port Role under “
Содержание DG-FS4528P
Страница 2: ......
Страница 4: ......
Страница 148: ...CHAPTER 5 Simple Network Management Protocol Configuring SNMPv3 Groups 148 ...
Страница 279: ...CHAPTER 8 Interface Configuration Showing Port or Trunk Statistics 279 Figure 130 Showing Port Statistics ...
Страница 289: ...CHAPTER 10 Address Table Settings Changing the Aging Time 289 4 Click Apply Figure 137 Setting the Address Aging Time ...
Страница 389: ...CHAPTER 17 VoIP Traffic Configuration Configuring Telephony OUI 389 ...
Страница 414: ...CHAPTER 18 Multicast Filtering Multicast VLAN Registration 414 Figure 216 Configuring Static MVR Receiver Group Members ...
Страница 515: ...CHAPTER 22 System Management Commands UPnP 515 TTL 20 Console ...
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Страница 973: ...DG FS4528P ...