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Native VLAN Mismatch

We have a Catalyst 2924XL with 4 port fiber module, each goes to another 2924 switch, usually port 24. I am getting this error message on the switches that are connected to the backbone switch via fiber:

%CDP-4-NATIVE_VLAN_MISMATCH: Native VLAN mismatch discovered on FastEthernet0/24 (0), with SWI01_RPCHM01.rpc.net FastEthernet1/1 (1)

Of course the interface is different with all the errors, 1/1, 1/2, 1/3, 1/4.

Whats strange about this is every port on all of the switches are assigned to VLAN 1, the default VLAN. I did a show vlan and everything looks fine.

Any Ideas?

geoffryn

What does a "sho cdp nei" say?

tduplantis

ASKER

This is the core router.

RTR03_RPCHM01 Fas 0/24 150 R 2620 Fas 0/0
RTR01_RPCHM01 Fas 0/24 153 R 3620 Eth 0/0
SWI07_RPCHM01 Fas 1/2 172 S WS-C2924C-Fas 0/24
SWI06_RPCHM01 Fas 1/1 155 S WS-C2924C-Fas 0/24
SWI04_RPCHM01 Fas 1/4 177 S WS-C2924C-Fas 0/24
SWI03_RPCHM01 Fas 1/3 158 S WS-C2924C-Fas 0/24

This is SWI07_RPCHM01

SWI01_RPCHM01.rpc Fas 0/24 149 T S WS-C2924M-Fas 1/2
SWI08_RPCHM01 Fas 0/23 152 T S WS-C2924C-Fas 0/24

I'm not sure why it is saying SWI01_RPCHM01.rpc(.net), you think this can cause a problem?

geoffryn

Can you post the VLAN config from both switches?

tduplantis

ASKER

CORE SWITCH:

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, Fa0/23, Fa0/24,
Fa1/1, Fa1/2, Fa1/3, Fa1/4
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

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

ONE THAT IS GETTING ERRORS:

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, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1 enet 100001 1500 - - - - - 1002 1003
1002 fddi 101002 1500 - - - - - 1 1003
1003 tr 101003 1500 1005 0 - - srb 1 1002
1004 fdnet 101004 1500 - - 1 ibm - 0 0
1005 trnet 101005 1500 - - 1 ibm - 0 0
SWI06_RPCHM01#

geoffryn

Do you have any ports configured as trunks?

tduplantis

ASKER

Yes, I have 7 of them setup on the core switch. Here is config:

Building configuration...

Current configuration:
!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname SWI01_RPCHM01
!
no logging console
enable secret 5 $1$JE5M$SJwn.lTMBNQkRMevTzD0d0
!
!
!
!
!
!
spanning-tree vlan 1 priority 100
ip subnet-zero
!
!
!
interface FastEthernet0/1
description XXXXX
duplex full
speed 100
port group 1
spanning-tree portfast
!
interface FastEthernet0/2
description XXXXX
duplex full
speed 100
port group 1
spanning-tree portfast
!
interface FastEthernet0/3
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/4
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/5
description XXXXX
duplex full
speed 100
port group 3
spanning-tree portfast
!
interface FastEthernet0/6
description XXXXX
duplex full
speed 100
port group 3
spanning-tree portfast
!
interface FastEthernet0/7
description XXXXX
duplex full
speed 100
port group 4
spanning-tree portfast
!
interface FastEthernet0/8
description XXXXX
duplex full
speed 100
port group 4
spanning-tree portfast
!
interface FastEthernet0/9
description XXXXX
duplex full
speed 100
port group 5
spanning-tree portfast
!
interface FastEthernet0/10
description XXXXX
duplex full
speed 100
port group 5
spanning-tree portfast
!
interface FastEthernet0/11
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/12
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/13
description XXXXX
duplex full
speed 100
port group 7
spanning-tree portfast
!
interface FastEthernet0/14
description XXXXX
duplex full
speed 100
port group 7
spanning-tree portfast
!
interface FastEthernet0/15
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/16
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/17
spanning-tree portfast
!
interface FastEthernet0/18
description XXXXX
duplex full
speed 100
spanning-tree portfast
!
interface FastEthernet0/19
spanning-tree portfast
!
interface FastEthernet0/20
spanning-tree portfast
!
interface FastEthernet0/21
!
interface FastEthernet0/22
spanning-tree portfast
!
interface FastEthernet0/23
spanning-tree portfast
!
interface FastEthernet0/24
description 12 Port 3COM Switch (Connected to PORT 1)
!
interface FastEthernet1/1
!
interface FastEthernet1/2
!
interface FastEthernet1/3
!
interface FastEthernet1/4
!
interface VLAN1
ip address 10.1.3.4 255.255.255.0
no ip directed-broadcast
no ip route-cache
!
ip default-gateway 192.168.1.1
snmp-server engineID local 00000009020000502AE4B0C0
snmp-server community private RW
snmp-server community public RO
snmp-server location 2nd Floor - RPC-Houma, LA
snmp-server contact David Landry
snmp-server chassis-id Sun
banner motd ^C
WARNING: The unauthorized use of devices or the tampering with access
to this network and its resources are CRIMINAL offenses!

***** ALL VIOLATORS ARE SUBJECT TO PROSECUTION *****^C
!
line con 0
transport input none
stopbits 1
line vty 0 4
password 7 050A081B2D495C5B4A
login
line vty 5 15
password 7 050A081B2D495C5B4A
login
!
end

SWI01_RPCHM01#

tduplantis

ASKER

Strange, I just noticed that default gateway statement in there, that shouldn't be in there at all.

tduplantis

ASKER

Well it should be, but its wrong. I corrected it, wonder if that was causing the problem? Especially considering all the other switches are pointed to the proper default gateway.

ASKER CERTIFIED SOLUTION

geoffryn

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tduplantis

ASKER

Well it should be, but its wrong. I corrected it, wonder if that was causing the problem? Especially considering all the other switches are pointed to the proper default gateway.

tduplantis

ASKER

We are not using vlans for anything.

tduplantis

ASKER

This has been resolved and was a cosmetic error only. One of our switches was running Version 12.0(5.4)WC(1) which has a bug associated with CDP version 2. We set all switches to CDP version 1 and the error went away. Thanks everyone for your responses.

tduplantis

ASKER

Thanks Geoffryn for your help on this, I called Cisco to get is resolved, but I learned a lot from our discussion. Have a great one!