STP (Spanning tree protocol)
.2 4 STP
:
:
Case #1

, , . VLAN 1. , (, / ). , A C Ethernet (10 ). FastEthernet.

show spanning-tree
A C. , C Ethernet 0/13 , FastEthernet 0/14 . . , 10 , 100 . :
- , .
- , . Ethernet , Fast Ethernet, FastEthernet.
Ethernet 0/13?

, Ethernet 0/13 FastEthernet0/14 . , interface Ethernet 0/13.

, , - 19 ( FastEthernet).
SwitchC(config)#interface Ethernet 0/13 SwitchC(config-if)#no spanning-tree cost 19
cost.

, cost, , . FastEthernet 0/14 , Ethernet 0/13 100 ( Ethernet). !
: , , , .
Case #2

, . (FastEthernet). A VLAN 10, :

, ... A , FastEthernet 0/17 . , . B , . .

, A B VLAN 10. C, , VLAN 10. ?


. VLAN 10 C. , VLAN 10.

. , VLAN 10 . , :
- VLAN 10 .
- Spanning- VLAN 10.
, VLAN 10 C, , , ?
SwitchC(config)#spanning-tree vlan 10

! VLAN 10 ... ! , . , , - , , , . , :
SwitchC(config)#interface fa0/1 SwitchC(config-if)#no spanning-tree vlan 10 SwitchC(config)#
no spanning-tree vlan 10
, , . , , , . VLAN 10 ... !
: , .
Case #3

! ... . :

. , FastEthernet 0/16 B C ? A . , , ? ! ... FastEthernet 0/16 0/17 C , C ID . , , C BPDU .
? , BPDU, . BPDU - MAC access-lists, VLAN access-maps - spanning-tree toolkit?
SwitchA#show vlan access-map SwitchB#show vlan access-map SwitchC#show vlan access-map
VLAN access maps.
SwitchA#show access-lists SwitchB#show access-lists SwitchC#show access-lists
...


port security... , ?

- ! BPDU FastEthernet 0/16 0/17 B. - C BPDU B.
SwitchB(config)#interface fa0/16 SwitchB(config-if)#no spanning-tree bpdufilter enable SwitchB(config-if)#interface fa0/17 SwitchB(config-if)#no spanning-tree bpdufilter enable
BPDU.

, FastEthernet 0/16 0/17 . ... !
: , BPDU .
Case #4

. A VLAN 10. FastEthernet .

show spanning-tree vlan 10
, . , - B FastEthernet 0/16 . , FastEthernet 0/13 ? , FastEthernet 0/16.

show spanning-tree interface
, spanning-tree . , VLAN 1, FastEthernet 0/13 0/14.
, , , :

-, , VLAN. spanning-tree no spanning-tree vlan X. VLAN 10, FastEthernet 0/16 0/17.

, VLAN 10, , . show interfaces switchport, , VLAN 10 FastEthernet 0/13 0/14. . , , VLAN 1.
SwitchB(config)#interface fa0/13 SwitchB(config-if)#switchport mode trunk SwitchB(config-if)#interface fa0/14 SwitchB(config-if)#switchport mode trunk
, VLAN 10 .

, . VLAN 10 FastEthernet 0/13 0/14, , FastEthernet 0/13 . !
: , VLAN , .
, EtherChannel.