Another 2950 problem

[luvcisco]

I am trying to connect 6 2950s to a 6509 switch via portbased vlan. We supernetted the ip and herewith use an extended VLAN. All switches will have the same Vlan applied, lets say Vlan 1500. Her is the config of one of the switches:
The port on the 6509 is configured for VLAN1500

version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname stupidswitch
!
aaa new-model
aaa authentication login default group tacacs+ line
aaa authentication login no_tacacs+ line
aaa authentication login no-tacacs+ line
!
ip subnet-zero
!
ip domain-name visa.com
ip name-server 10.x.x.x
ip name-server 10.x.x.x
vtp mode transparent
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
vlan 1500
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface FastEthernet0/25
!
interface FastEthernet0/26
!
interface FastEthernet0/27
!
interface FastEthernet0/28
!
interface FastEthernet0/29
!
interface FastEthernet0/30
!
interface FastEthernet0/31
!
interface FastEthernet0/32
!
interface FastEthernet0/33
!
interface FastEthernet0/34
!
interface FastEthernet0/35
!
interface FastEthernet0/36
!
interface FastEthernet0/37
!
interface FastEthernet0/38
!
interface FastEthernet0/39
!
interface FastEthernet0/40
!
interface FastEthernet0/41
!
interface FastEthernet0/42
interface FastEthernet0/43
!
interface FastEthernet0/44
!
interface FastEthernet0/45
!
interface FastEthernet0/46
!
interface FastEthernet0/47
!
interface FastEthernet0/48
!
interface GigabitEthernet0/1
description 6509switch 3/6
switchport access vlan 1500
!
interface GigabitEthernet0/2
!
interface Vlan1
no ip address
no ip route-cache
shutdown

interface Vlan1500
ip address 10.55.150.12 255.255.252.0
no ip route-cache
!
ip default-gateway 10.55.150.1
no ip http server

When I enable both interface on either switch I get nothing, not even a peep. I was thinking hardware but I tried three switches and the same thing happened. I applied the same config on all of them with the exception of modifying the ip address.

Also on another note, I believe speed and duplex cannot be applied on teh giga interface, am I correct or is tehre something else I am missing...what a day.
Thanks for all your help

Connie

 

[ADB100]

1st - I think you missed the concept of VLAN's?

2nd - Having a common VLAN across all your switches is a stupid idea; make each switch have its own unique VLAN

3rd - The recommended way of connecting Access switches to the Core/Distribution is using VLAN trunks, although if multiple VLAN's are not required at each Access switch you can use access ports as the uplinks

To get yourself working change the access VLAN of your access ports to the same as the Uplink, otherwise all you access ports will stay in VLAN 1 (default) and only have access to other ports on the same switch in VLAN 1.

interface fastethernet0/1
switchport mode access
switchport access vlan 1


I hope this helps but I really think you should get someone in to deploy this correctly, not knowing is your worst enemy when things go wrong and your applications guys come looking for blood.....

Andy

 

[ADB100]

Sorry it should have read:

interface fastethernet0/1
switchport mode access
switchport access vlan 1500

Andy

 

[ADB100]

You will need a crossover-cable as well if both sides are 10/100/1000 interfaces - If one side (6500) is a 1000BaseT ONLY then it should work with a straight-cable, otherwise you will need a Gigabit Ethernet 1000BaseT Cross-Over:

http://www.cabling-design.com/references/pinouts/1000base_t_crossover.shtml

Andy

 

[luvcisco]

Thanks Andy for your input, however I am very familiar with vlans and the trunking principle. There is a reason why I deploy these switches the way they are. My question did not incorporate if this is a correct topology but rather if there could be another reason than a layer 1 problem that I am missing here between these two switches.
Also my uplink is a giga fiber connection and I do want to enable VLAN1.
Don't jump so quickly to conclusions and open your mind and knowledge. I am working with a company that has thousands of switches, routers firewalls etc...there is a logic behind this madness.
Thanks for your time.
Connie

 

[ADB100]

Connie, I wasn't jumping to conclusions - I simply looked at the configuration you posted and stated the obvious..... sorry if you took offence to it, I have been deploying networks for a long time and to be implementing Layer-2 networks these days is best avoided. The benefits of Layer-3 simply outweigh Layer-2 everytime, sorry but that is how it is \

A Layer-1/2 problem is likely to be the obvious - cables or GBIC's. Have you tried connecting the 2950 direct to the 6500 using a fibre patch cable (making sure to cross TX to RX....). If you are using LX/LH GBIC's on MultiMode fibre then you need to make sure you are using mode-conditioning patch cables.

Andy

 

[lui3]

Connie,

Which switch configuration are you posting here? The 2950 or the 6509 configuration.

If you have 6509 with uplink ports to 6 2950s then leave the 2950s at the defaults and change the switchport access vlan 1500 to apply on the 6509 ports.

The way it works is this. If you use the command

switchport access vlan x

you are essentially saying all traffic that comes in this port is on vlan x. there is not a concept of native vlan or vlans for that matter. the only time that vlan encapsulation takes place is when traffic is received on the port. In the case of

switch port access vlan 1500

on the switchport

all traffic received on that switchport will belong to vlan 1500 (on that switch) as it passes through the switch that received the traffic. When traffic is transmitted back out the switchport the vlan header information is stripped from the that packet. Since the port is not a trunk there is no need to further tag the traffic for reception by the down stream switch.

The receiving switch can reenncapsulated the received traffic to whatever vlan it wants to traffic to belong. Vlan tagging is only passed along on vlan trunks. Access ports strip vlan tagging since the downstream receiver assumes all traffic belongs to the native vlan configured on that device. Vlan 1 by default.

for the 6509 configuration the following would be configured


set vlan x/x 1500

for each port connecting to the 2950s

then all the 2950s would belong to vlan 1500

let me know if this helps/

Lui3
CCNP,CCDA,A+/Net+
Cisco Wireless Specialization

 

[luvcisco]

OK, thanks everybody for your input. I had my hardware installation guys test the fiber since they were connected via two patch panels. It seems once the GBICS were rolled on the 6509 the connections came up. Again all input was appreciated and thanks for taken out the time to evaluate the problem and write back.

Connie