DLS2#sh int trunk
Port Mode Encapsulation Status Native vlan
Po2 on 802.1q trunking 900
Po10 on 802.1q trunking 900
Port Vlans allowed on trunk
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans allowed and active in management domain
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans in spanning tree forwarding state and not pruned
Po2 10,20,30,100
Po10 10,20,30,50,100
note vlan 50 is not forwarding on po2...
DLS2#sh run int po2
Building configuration...
Current configuration : 223 bytes
!
interface Port-channel2
description Channel to ALS1
switchport trunk encapsulation dot1q
switchport trunk native vlan 900
switchport trunk allowed vlan 10,20,30,100
switchport mode trunk
switchport nonegotiate
as you can see that's by design... however it is forwarding on po10 although it is down...
DLS2#sh int vlan 50
Vlan50 is administratively down, line protocol is down
Hardware is EtherSVI, address is 0016.479e.5fc6 (bia 0016.479e.5fc6)
Internet address is 10.1.50.253/24
DLS2#sh spann vlan 50 | b Interface
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 12 128.128 P2p
spanning tree believes it is still forwarding simply because it's allowed on the trunk regardless of it's operational state...
DLS2#sh run int po10
Building configuration...
Current configuration : 227 bytes
!
interface Port-channel10
description Channel to DLS1
switchport trunk encapsulation dot1q
switchport trunk native vlan 900
switchport trunk allowed vlan 10,20,30,50,100
switchport mode trunk
switchport nonegotiate
of course dls1 can't ping it and it's getting no hsrp love...
DLS1>ping 10.1.50.253
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.50.253, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
DLS1>sh stand brie
P indicates configured to preempt.
|
Interface Grp Pri P State Active Standby Virtual IP
Vl10 10 110 P Active local 10.1.10.253 10.1.10.254
Vl20 20 100 P Standby 10.1.20.253 local 10.1.20.254
Vl30 30 110 P Active local 10.1.30.253 10.1.30.254
Vl50 50 100 P Active local unknown 10.1.50.254
Vl100 100 110 P Active local 10.1.100.253 10.1.100.254
hsrp was nice enough to take over on dls1, however...
DLS2#sh stand brie
P indicates configured to preempt.
|
Interface Grp Pri P State Active Standby Virtual IP
Vl10 10 100 P Standby 10.1.10.252 local 10.1.10.254
Vl20 20 110 P Active local 10.1.20.252 10.1.20.254
Vl30 30 100 P Standby 10.1.30.252 local 10.1.30.254
Vl50 50 110 P Init unknown unknown 10.1.50.254
Vl100 100 100 P Standby 10.1.100.252 local 10.1.100.254
once i disallow it on the trunk:
DLS2#sh spann vlan 50
Spanning tree instance(s) for vlan 50 does not exist.
it stops showing up in forwarding state...
DLS2#sh int trunk
Port Mode Encapsulation Status Native vlan
Po2 on 802.1q trunking 900
Po10 on 802.1q trunking 900
Port Vlans allowed on trunk
Po2 10,20,30,100
Po10 10,20,30,100
Port Vlans allowed and active in management domain
Po2 10,20,30,100
Po10 10,20,30,100
Port Vlans in spanning tree forwarding state and not pruned
Po2 10,20,30,100
Po10 10,20,30,100
and until it is added to the trunk, although it is no longer shut, it is up, down because it is not an active member of any port...
DLS2#sh int vlan 50
Vlan50 is up, line protocol is down
Hardware is EtherSVI, address is 0016.479e.5fc6 (bia 0016.479e.5fc6)
Internet address is 10.1.50.253/24
the point is it doesn't get pruned from the trunk, until it is taken out of allowed manually... allowed prevents dynamic pruning... makes sense...
DLS2(config)#int po10
DLS2(config-if)#sw trunk allowed vlan 10,20,30,50,100
DLS2(config-if)#
Jan 22 23:59:11: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan50, changedp
Jan 22 23:59:13: %HSRP-5-STATECHANGE: Vlan50 Grp 50 state Listen -> Active
DLS2(config-if)#do sh int trunk
Port Mode Encapsulation Status Native vlan
Po2 on 802.1q trunking 900
Po10 on 802.1q trunking 900
Port Vlans allowed on trunk
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans allowed and active in management domain
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans in spanning tree forwarding state and not pruned
Po2 10,20,30,100
Po10 10,20,30,50,100
DLS2(config-if)#sw trunk allowed vlan 10,20,30,50,100
DLS2(config-if)#
Jan 22 23:59:11: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan50, changedp
Jan 22 23:59:13: %HSRP-5-STATECHANGE: Vlan50 Grp 50 state Listen -> Active
DLS2(config-if)#do sh int trunk
Port Mode Encapsulation Status Native vlan
Po2 on 802.1q trunking 900
Po10 on 802.1q trunking 900
Port Vlans allowed on trunk
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans allowed and active in management domain
Po2 10,20,30,100
Po10 10,20,30,50,100
Port Vlans in spanning tree forwarding state and not pruned
Po2 10,20,30,100
Po10 10,20,30,50,100
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
Po10 Desg FWD 12 128.128 P2p
