Problems to comunicate Cisco 3750 with 2960

[Junior27]

Hi,

We have a Cisco 3750 with 12 Fiber Ports. Went this switch was connected to old 2950 works fine but know I am changing to 2960 switches and dont communicate between them. In the Cisco 3750 the trunk port are setup with;

switchport trunk encapsulation dot1q

switchport mode trunk

In the 2960 with

switchport mode trunk

because the 2960 dont have the option of the encapsulation dot1q

And I cant ping from the 3750 to the 2960 and vise-versa 

Any recomendation or additional instruction that I need to add to the 2960 switches?

Please let me know.

Thanks

[Leo Laohoo]

Post the complete output to the command "sh interface trunk".

[balaji.bandi]

adding to other post can you also post 

show vlan 

show run interface XX (part of trunk)

[Junior27]

Switch#sh run interface vlan 10
Building configuration...

Current configuration : 111 bytes
!
interface Vlan10
ip address 172.10.5.11 255.255.248.0
no ip route-cache
no ip mroute-cache
shutdown
end
Switch#ping 172.10.5.11

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.10.5.11, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
Switch#sh int trunk

Port Mode Encapsulation Status Native vlan
Gi3/0/1 on 802.1q trunking 1
Gi3/0/12 on 802.1q trunking 1

Port Vlans allowed on trunk
Gi3/0/1 1-4094
Gi3/0/12 1-4094

Port Vlans allowed and active in management domain
Gi3/0/1 1
Gi3/0/12 1

Port Vlans in spanning tree forwarding state and not pruned
Gi3/0/1 1
Gi3/0/12 1
Switch#

[balaji.bandi]

High level

interface Vlan10
ip address 172.10.5.11 255.255.248.0
no ip route-cache
no ip mroute-cache
shutdown   <--- no shut
end

test and advise.

[Junior27]

I already made the no shut went I saw that is shutdown
but continue with the same problem that no traffic between the 3750 and the 2 2960.
In the 2960 I can ping the vlan 10 with any problem but in the 3750 I cant ping it

[balaji.bandi]

Can you post both the device full configuration.

show run from both the devices.

[Junior27]

Switch 3750
sh conf
Using 2194 out of 524288 bytes
version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname Switch
boot-start-marker
boot-end-marker
enable secret 5 $1$uz8x$CZaA7NOpnMspdsWNVWZbA/
enable password Cisco
no aaa new-model
switch 3 provision ws-c3750g-12s
system mtu routing 1500
spanning-tree mode pvst
spanning-tree extend system-id
vlan internal allocation policy ascending
interface GigabitEthernet3/0/1
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/2
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/3
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/4
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/5
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/6
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/7
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/8
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/9
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/10
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/11
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface GigabitEthernet3/0/12
description trunk port
switchport trunk encapsulation dot1q
switchport mode trunk
interface Vlan1
ip address 192.168.120.11 255.255.248.0
shutdown
interface Vlan10
ip address 172.10.5.11 255.255.248.0
no ip route-cache
no ip mroute-cache
ip classless
ip http server
ip http secure-server
line con 0
line vty 0 4
password cisco
login
line vty 5 15
password cisco
login
end

Switch#ping 172.10.5.11
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.10.5.11, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
Switch#ping 172.10.5.15
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.10.5.15, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

Switch 2960
Using 6320 out of 524288 bytes
! Last configuration change at 06:25:15 UTC Wed Mar 30 2011
! NVRAM config last updated at 06:26:09 UTC Wed Mar 30 2011
version 15.0
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname Switch
boot-start-marker
boot-end-marker
enable secret 5 $1$GbJ3$njIVFNjewYlaEkk4G4KUU1
enable password Cisco
no aaa new-model
switch 1 provision ws-c2960s-48fpd-l
crypto pki trustpoint TP-self-signed-3269795968
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-3269795968
revocation-check none
rsakeypair TP-self-signed-3269795968
crypto pki certificate chain TP-self-signed-3269795968
certificate self-signed 01 nvram:IOS-Self-Sig#1.cer
spanning-tree mode pvst
spanning-tree extend system-id
vlan internal allocation policy ascending
interface FastEthernet0
no ip address
shutdown
interface GigabitEthernet1/0/1
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/2
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/3
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/4
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/5
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/6
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/7
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/8
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/9
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/10
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/11
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/12
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/13
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/14
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/15
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/16
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/17
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/18
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/19
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/20
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/21
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/22
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/23
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/24
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/25
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/26
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/27
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/28
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/29
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/30
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/31
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/32
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/33
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/34
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/35
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/36
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/37
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/38
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/39
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/40
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/41
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/42
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/43
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/44
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/45
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/46
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/47
description vlan 1
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/48
description vlan 10
switchport access vlan 10
switchport mode access
spanning-tree portfast
interface GigabitEthernet1/0/49
description port trunk
switchport mode trunk
interface GigabitEthernet1/0/50
interface TenGigabitEthernet1/0/1
interface TenGigabitEthernet1/0/2
interface Vlan1
ip address 192.168.120.15 255.255.255.0
shutdown
interface Vlan10
ip address 172.10.5.15 255.255.248.0
no ip route-cache
ip http server
ip http secure-server
line con 0
line vty 0 4
password cisco
login
line vty 5 15
password cisco
login
end

Switch#ping 172.10.5.15
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.10.5.15, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
Switch#ping 172.10.5.11
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.10.5.11, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
Switch#

[balaji.bandi · Accepted solution]

As per your config my understanding

3750 (port  Gig 3/0/1 ) ---Connected --- (Port  Gig 1/0/49) ---2960 

Is this correct  ?

If So on your 3750 all the ports are in Trunk Mode.

Form testing  on 3750 do following steps : ( No changes required on 2960X side for now).

config t

!

Default interface GigabitEthernet3/0/2
Default interface GigabitEthernet3/0/3

!

interface GigabitEthernet3/0/2

switchport mode access

switchport access vlan 10
!

interface GigabitEthernet3/0/3

switchport mode access

switchport access vlan 1

!

interface Vlan1

no shutdown

!

interface Vlan10

no shutdown

!

Try ping locally 

Switch#ping 172.10.5.11

remote  ping 

Switch#ping 172.10.5.15

Switch#ping 192.168.120.11

remote  ping 

Switch#ping 192.168.120.15

Post the results.  

[Junior27]

Hi Balaji.bandi,

You are the best. I configure the instruction you send me and now is working. I saw that the 3750 don't create the vlan 10 until I setup a port with this vlan and that was the problem.

Thanks a lot