Ports blocked from spanning tree

I am trying to replace a failing 2950 switch (DT01) with a new switch. Both switches are connected to an ASA. All ports on DT01 are assigned to default vlan 1.

interface Ethernet0/1
 description DT01-0/23
 switchport access vlan 100
!
interface Ethernet0/2
 description SW02-0/47
 switchport trunk allowed vlan 50,80,100,800
 switchport mode trunk
!

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When I try to bring up the new switch (SW02) , the vlan are blocked from spanning tree despite nothing is plugged in to the new switch (SW02). All ports on SW02 are configured to use vlan100 with access mode. (vlan 1 and 100 are in the same network, 192.168.200.0/24).

DT01#sh spanning-tree summary 
Switch is in pvst mode
Root bridge for: VLAN0100
EtherChannel misconfig guard is enabled
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
UplinkFast                   is disabled
BackboneFast                 is disabled
Pathcost method used         is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001                     0         0        0         10         10
VLAN0100                     0         0        0          2          2
---------------------- -------- --------- -------- ---------- ----------
2 vlans                      0         0        0         12         12

#sh spanning-tree 

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID    Priority    32769
             Address     0014.a8ba.2340
             Cost        38
             Port        24 (FastEthernet0/24)
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32769  (priority 32768 sys-id-ext 1)
             Address     001a.2fc0.f7c0
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/2            Desg FWD 19        128.2    Edge P2p 
Fa0/4            Desg FWD 19        128.4    Edge P2p 
Fa0/8            Desg FWD 19        128.8    Edge P2p 
Fa0/10           Desg FWD 19        128.10   Edge P2p 
Fa0/12           Desg FWD 19        128.12   Edge P2p 
Fa0/13           Desg FWD 19        128.13   Edge P2p 
Fa0/16           Desg FWD 19        128.16   P2p 
Fa0/21           Desg FWD 19        128.21   P2p 
Fa0/23           Desg FWD 19        128.23   Edge P2p 
Fa0/24           Root FWD 19        128.24   P2p

VLAN0100
  Spanning tree enabled protocol ieee
  Root ID    Priority    32868
             Address     001a.2fc0.f7c0
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32868  (priority 32768 sys-id-ext 100)
             Address     001a.2fc0.f7c0
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/23           Desg FWD 19        128.23   Edge P2p 
Fa0/24           Desg FWD 19        128.24   P2p 

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SW02#sh spanning-tree summary 
Switch is in pvst mode
Root bridge for: VLAN0001, VLAN0050, VLAN0100, VLAN0800
EtherChannel misconfig guard is enabled
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
UplinkFast                   is disabled
BackboneFast                 is disabled
Pathcost method used         is short



Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001                     1         0        0          0          1
VLAN0050                     0         0        0          1          1
VLAN0100                     1         0        0          0          1
VLAN0800                     0         0        0          1          1
---------------------- -------- --------- -------- ---------- ----------
4 vlans                      2         0        0          2          4

SWCH02#sh spanning-tree 

VLAN0001
  Spanning tree enabled protocol ieee
  Root ID    Priority    32769
             Address     0015.c620.2240
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32769  (priority 32768 sys-id-ext 1)
             Address     0015.c620.2240
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/47           Desg BKN*19        128.47   P2p *PVID_Inc

          
VLAN0050
  Spanning tree enabled protocol ieee
  Root ID    Priority    32818
             Address     0015.c620.2240
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32818  (priority 32768 sys-id-ext 50)
             Address     0015.c620.2240
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/47           Desg FWD 19        128.47   P2p 

VLAN0100
  Spanning tree enabled protocol ieee
  Root ID    Priority    32868
             Address     0015.c620.2240
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    32868  (priority 32768 sys-id-ext 100)
             Address     0015.c620.2240
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/47           Desg BKN*19        128.47   P2p *PVID_Inc

          
VLAN0800
  Spanning tree enabled protocol ieee
  Root ID    Priority    33568
             Address     0015.c620.2240
             This bridge is the root
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    33568  (priority 32768 sys-id-ext 800)
             Address     0015.c620.2240
             Hello Time   2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time 300

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/47           Desg FWD 19        128.47   P2p 

# sh log
Apr  4 16:23:13: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 1 on FastEthernet0/47 VLAN100.
.Apr  4 16:23:13: %SPANTREE-2-BLOCK_PVID_PEER: Blocking FastEthernet0/47 on VLAN0001. Inconsistent peer vlan.
.Apr  4 16:23:13: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking FastEthernet0/47 on VLAN0100. Inconsistent local vlan.

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LVL 21
MazdajaiAsked:
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Salah Eddine ELMRABETTechnical Lead Manager (Owner)Commented:
Hi,,

Is the first command lines are from DT01? if so why connecting Fa0/1 to Fa0/23??

On SW02, the logs shows that the VLAN misunderstood, do you have ISL configured?

If you want to make a HW replace after failed Switch, do you have a backup configuration file used to configure the new switch or you are configuring the new switch from scrach?

Please post configuration and show vlan output in order to understand you topology.

Best Regards.

Salah
Don JohnstonInstructorCommented:
You don't have a spanning-tree problem.  The ports aren't "blocked", they're "broken". This is due to what appears to be a native VLAN mismatch.  The native VLAN on each end of the link has to be the same.
MazdajaiAuthor Commented:
Salah,

They are connected to an ASA. These are 802.1Q. I have a back up config but I would like to migrate away from default vlan 1 and add new vlans on SW02 (replacement). That's the reason I trunk couple new vlans on it.

ASA # sh switch vlan
VLAN Name                             Status    Ports
---- -------------------------------- --------- -----------------------------
1    -                                down      Et0/7
40   outside                          up        Et0/0
50   guest50                          up        Et0/2, Et0/3, Et0/4, Et0/5
                                                Et0/6
80   prod80                           up        Et0/2, Et0/3, Et0/4, Et0/5
                                                Et0/6
100  inside                           up        Et0/1, Et0/2, Et0/3, Et0/4
                                                Et0/5, Et0/6
200  voice200                         down
500  serv500                          down
800  mgmt800                          up        Et0/2, Et0/3, Et0/4, Et0/5
                                                Et0/6

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DT01#sh vlan

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/1, Fa0/2, Fa0/3, Fa0/4
                                                Fa0/5, Fa0/6, Fa0/7, Fa0/8
                                                Fa0/9, Fa0/10, Fa0/11, Fa0/12
                                                Fa0/13, Fa0/14, Fa0/15, Fa0/16
                                                Fa0/17, Fa0/18, Fa0/19, Fa0/20
                                                Fa0/21, Fa0/22, Gi0/1, Gi0/2
100  VLAN0100                         active
1002 fddi-default                     act/unsup
1003 token-ring-default               act/unsup
1004 fddinet-default                  act/unsup
1005 trnet-default                    act/unsup

VLAN Type  SAID       MTU   Parent RingNo BridgeNo Stp  BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1    enet  100001     1500  -      -      -        -    -        0      0
100  enet  100100     1500  -      -      -        -    -        0      0
1002 fddi  101002     1500  -      -      -        -    -        0      0
1003 tr    101003     1500  -      -      -        -    -        0      0
1004 fdnet 101004     1500  -      -      -        ieee -        0      0
1005 trnet 101005     1500  -      -      -        ibm  -        0      0

Remote SPAN VLANs
------------------------------------------------------------------------------


Primary Secondary Type              Ports
------- --------- ----------------- ------------------------------------------

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SW02#sh vlan

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/25, Fa0/26, Fa0/27, Fa0/28
                                                Fa0/29, Fa0/30, Fa0/31, Fa0/32
                                                Fa0/33, Fa0/34, Fa0/35, Fa0/36
                                                Fa0/37, Fa0/38, Fa0/39, Fa0/40
                                                Fa0/41, Fa0/42, Fa0/43, Fa0/44
                                                Fa0/45, Fa0/46, Fa0/48, Gi0/1
                                                Gi0/2
50   guest50                          active
100  prod100                          active    Fa0/1, Fa0/2, Fa0/3, Fa0/4
                                                Fa0/5, Fa0/6, Fa0/7, Fa0/8
                                                Fa0/9, Fa0/10, Fa0/11, Fa0/12
                                                Fa0/13, Fa0/14, Fa0/15, Fa0/16
                                                Fa0/17, Fa0/18, Fa0/19, Fa0/20
                                                Fa0/21, Fa0/22, Fa0/23, Fa0/24
500  serv500                          active
800  mgmt800                          active
1002 fddi-default                     act/unsup
1003 token-ring-default               act/unsup
1004 fddinet-default                  act/unsup
1005 trnet-default                    act/unsup

VLAN Type  SAID       MTU   Parent RingNo BridgeNo Stp  BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1    enet  100001     1500  -      -      -        -    -        0      0
50   enet  100050     1500  -      -      -        -    -        0      0
100  enet  100100     1500  -      -      -        -    -        0      0
500  enet  100500     1500  -      -      -        -    -        0      0
800  enet  100800     1500  -      -      -        -    -        0      0
1002 fddi  101002     1500  -      -      -        -    -        0      0
1003 tr    101003     1500  -      -      -        -    -        0      0
1004 fdnet 101004     1500  -      -      -        ieee -        0      0
1005 trnet 101005     1500  -      -      -        ibm  -        0      0

Remote SPAN VLANs
------------------------------------------------------------------------------


Primary Secondary Type              Ports
------- --------- ----------------- -----------------------------------------

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Don,
I didn't specify native vlan on these ones. I am confused here as spanning tree reporting they are blocked.
Is it possible to have vlan 100 coexist with vlan 1 and other switch? If not, any suggestion?

SW02#sh spanning-tree blockedports

Name                 Blocked Interfaces List
-------------------- ------------------------------------
VLAN0001             Fa0/47
VLAN0100             Fa0/47

Number of blocked ports (segments) in the system : 2

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Craig BeckCommented:
(vlan 1 and 100 are in the same network, 192.168.200.0/24).
Is it possible to have vlan 100 coexist with vlan 1 and other switch?
That's your problem.  The switch is seeing a BPDU with two VLAN IDs as native, and blocking the port.  Choose an unused VLAN ID as the native VLAN if you can, and don't use the same IP subnet on both VLANs.
MazdajaiAuthor Commented:
don't use the same IP subnet on both VLANs. 

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This is tough as I have some hard coded ip address deviced that are not easy migrated off. I will try it again this weekend. (Can't touch it during weekday)Can I temporary shut off spanning tree and turn it back on after moving all interfaces over?
Craig BeckCommented:
It's not hard.  You can run 2 IP ranges on one VLAN - that's OK.  What makes things difficult is managing STP with bridged VLANS, etc.
MazdajaiAuthor Commented:
Is it possible to disable STP temporary while I migrate the VLANs?
Craig BeckCommented:
You can disable STP globally, or per VLAN if you're running PVST, RPVST or MST.

no spanning-tree vlan 1,10,20-40

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