11-04-2002 05:46 PM - edited 03-02-2019 02:37 AM
I have a switch 2950 switch providing connectivity to remote site users through a connection to router. No trunking configured and being a stand-alone switch no VTP configured on switch therefore by default it configured as server with ver. 2. But, when I connect a sniffer to span traffic on uplink port that is the link between router 2621 and switch. I'm start receiving the packet with 802.1Q encapsulation that causes me to open each packet.
I'm wondering why in first place it encapsulation packet with 802.1Q.
Any help appreciated.
Thank in advance.
11-05-2002 01:22 AM
How is the uplink port configured, as well as the span port configured?
What may be happening is it may be trying to autoneg. trunking if there isn't a 'switchport mode access' command on these interfaces to define them as access ports only. The 2621 doesn't have any dot1q subinterfaces that the packets could be coming from? Perhaps the sniffer is displaying the traffic wrong - I've seen that before.
HTH, Erick
11-05-2002 05:34 PM
Bellow is switch configuration:
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname xxxxxxxxxxxxxxxxxxx
!
aaa new-model
aaa authentication login admin group tacacs+ line
aaa authentication enable default group tacacs+ enable
enable secret
!
clock timezone PST -8
ip subnet-zero
no ip finger
ip domain-name xxxxxxxxxxxxxxxxx
ip name-server xxxxxxxxxxxx
ip name-server xxxxxxxxxxxxxx
!
!
!
interface FastEthernet0/1
description sw. to router
duplex full
speed 100
!
interface FastEthernet0/2
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/3
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/4
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/5
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/6
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/7
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/8
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/9
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/10
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/11
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/12
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/13
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/14
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/15
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/16
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/17
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/18
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/19
duplex half
speed 10
spanning-tree portfast
!
interface FastEthernet0/20
description link to xxxxxxxxxxx
switchport mode access
duplex half
speed 10
!
interface FastEthernet0/21
duplex half
speed 10
!
interface FastEthernet0/22
duplex half
speed 10
!
interface FastEthernet0/23
duplex half
speed 10
!
interface FastEthernet0/24
duplex half
speed 10
!
interface Vlan1
ip address xxxxxxxxxxxxx xxxxxxxxxxxxxx
no ip route-cache
!
ip default-gateway xxxxxxxxxxx
no ip http server
logging trap notifications
logging 146.22.44.13
logging 146.22.44.10
access-list 10 permit xxxxxxxxxxxxxxxxx
access-list 10 permit xxxxxxxxxxxxxxxx
snmp-server engineID local 00000009020000087DEC7A00
snmp-server community xxxxxxxxxxxx RW 10
snmp-server community xxxxxxxxxxxxx RO
snmp-server contact xxxxxxxxxxxxxxxxxxxxxx
tacacs-server host xxxxxxxxxxxxxxxx
tacacs-server key keymaster
banner motd ^CCC
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
^C
!
line con 0
exec-timeout 15 0
password xxxxxxxxxxxxxxxxxxxx
login authentication admin
transport input none
stopbits 1
line vty 0 4
exec-timeout 15 0
password 7 xxxxxxxxxxxxxxxxxx
login authentication admin
line vty 5 15
!
ntp clock-period xxxxxxxxxx
ntp server xxxxxxxxxxx
!
monitor session 1 source interface Fa0/1
monitor session 1 destination interface Fa0/16
11-05-2002 04:41 AM
It's a bug. Use 12.1.11ea1 or later.
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