Curso personalizado de capacitación al area sistemas para NNN ( reservado )
5/1 al 27/1 del 2010, Academia local Cisco, Rosario
Instructor: Ernesto Vilarrasa
Administración / Spanning tree / VLAN / Wireless LAN / Seguridad
Parte 1
Parte 3
Spannning Tree: para dar redundancia a la topología, agregamos un segundo enlace
entre los switchs. Para ello, también debemos configurar los ports como trunk:
SW_LAYER3#
SW_LAYER3#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW_LAYER3(config)#int gig 0/2
SW_LAYER3(config-if)#switchport mode trunk
%LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/2,
changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface
GigabitEthernet0/2, changed state to up
SW_LAYER3(config-if)#end
SW_LAYER3#
SW_2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW_2(config)#int gig 1/2
SW_2(config-if)#switchport mode trunk
SW_2(config-if)#end
SW_2#
%SYS-5-CONFIG_I: Configured from console by console
SW_2#
SW_LAYER3#show spanning-tree summ
Switch is in pvst mode
Root bridge for: default vlan10 vlan20 seguridad
pruebas
Extended system ID is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is disabled
EtherChannel misconfig guard is disabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name
Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- --------
---------- ----------
VLAN0001 0
0 0 3 3
VLAN0010 0
0 0 2 2
VLAN0020 0
0 0 2 2
VLAN0030 0
0 0 2 2
VLAN0050 0
0 0 2 2
---------------------- -------- --------- --------
---------- ----------
5 vlans 0
0 0 11 11
SW_LAYER3#
SW_1#sh spanning-tree summary
Switch is in pvst mode
Root bridge for:
Extended system ID is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is disabled
EtherChannel misconfig guard is disabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name
Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- --------
---------- ----------
VLAN0001 1
0 0 1 2
VLAN0010 1
0 0 2 3
VLAN0020 1 0 0 2 3
VLAN0030 1 0 0 1 2
VLAN0050 1
0 0 1 2
---------------------- -------- --------- --------
---------- ----------
5 vlans 5
0 0 7 12
SW_1#
SW_2#sh spanning-tree summary
Switch is in pvst mode
Root bridge for:
Extended system ID is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is disabled
EtherChannel misconfig guard is disabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name
Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- --------
---------- ----------
VLAN0001 0
0 0 4 4
VLAN0010 0
0 0 2 2
VLAN0020 0
0 0 2 2
VLAN0030 0
0 0 2 2
VLAN0050 0
0 0 2 2
---------------------- -------- --------- --------
---------- ----------
5 vlans 0
0 0 12 12
SW_2#
Verficación:
Escenario 1:
Cae el enlace Switch_1 – SW_LAYER3: inmediatamente spannning-tree recalcula la nueva
ruta hacia SW_LAYER3, luego de aproximadamente 50 segundos, el vínculo de backup
entra en línea.
SW_1#sh spanning-tree summary
Switch is in pvst mode
Root bridge for:
Extended system ID is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is disabled
EtherChannel misconfig guard is disabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name
Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- --------
---------- ----------
VLAN0001 0
0 0 1 1
VLAN0010 0
0 0 2 2
VLAN0020 0
0 0 2 2
VLAN0030 0 0 0 1 1
VLAN0050 0
0 0 1 1
---------------------- -------- --------- --------
---------- ----------
5 vlans 0
0 0 7
7
SW_1#
Al reestablecerse el vínculo spanning.tree se recalcula, por lo que se pierde la conectividad
Switch_1 – SW_LAYER3 nuevamente
por hasta 50 segundos.
Escenario 2:
Cae el enlace Switch_2 – SW_LAYER3: inmediatamente spannning-tree recalcula la nueva
ruta hacia SW_LAYER3, luego de aproximadamente 50 segundos, el vínculo de backup
entra en línea.
Switch is in pvst mode
Root bridge for:
Extended system ID
is enabled
Portfast Default is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default is disabled
EtherChannel misconfig guard is disabled
UplinkFast is disabled
BackboneFast is disabled
Configured Pathcost method used is short
Name
Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- --------
---------- ----------
VLAN0001 0 0 0 2 2
VLAN0010 0
0 0 3 3
VLAN0020 0
0 0 3 3
VLAN0030 0
0 0 2 2
VLAN0050 0
0 0 2 2
---------------------- -------- --------- --------
---------- ----------
5 vlans 0
0 0 12 12
SW_1#