2950 trunk

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John Tressle 19 years ago

Help! I'm trying to setup a trunk between 2 x 2950 switches so that I can access all vlans from both switches. Devices patched into vlan1 can see each other no problem but I can't seem to get any other vlans working over the trunk. I'm testing by pinging the devices patched into the appropriate vlans on the other switch - there's no routing involved. Configs of both switches are below - any help would be greatly appreciated!

Cheers, John

SWITCH1#show running-config Building configuration...

Current configuration : 3339 bytes ! version 12.1 no service pad service timestamps debug uptime service timestamps log datetime no service password-encryption service sequence-numbers ! hostname SWITCH1 ! enable secret 5 ------------------- enable password ------------------- ! ip subnet-zero no ip finger ! ! no spanning-tree vlan 2 no spanning-tree vlan 3 no spanning-tree vlan 4 no spanning-tree vlan 5 no spanning-tree vlan 6 ! ! interface FastEthernet0/1 switchport mode access duplex full speed 100 ! interface FastEthernet0/2 switchport access vlan 5 switchport mode access duplex full speed 100 ! interface FastEthernet0/3 switchport mode access ! interface FastEthernet0/4 switchport mode access duplex full speed 100 ! interface FastEthernet0/5 switchport mode access duplex full speed 100 ! interface FastEthernet0/6 switchport mode access ! interface FastEthernet0/7 switchport mode access ! interface FastEthernet0/8 switchport mode access ! interface FastEthernet0/9 switchport access vlan 3 switchport mode access duplex full speed 10 ! interface FastEthernet0/10 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/11 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/12 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/13 switchport access vlan 3 switchport mode access duplex full speed 10 ! interface FastEthernet0/14 switchport access vlan 2 switchport mode access duplex full speed 10 ! interface FastEthernet0/15 switchport access vlan 2 switchport mode access duplex full speed 10 ! interface FastEthernet0/16 switchport access vlan 2 switchport mode access duplex full speed 10 ! interface FastEthernet0/17 switchport access vlan 2 switchport mode access duplex full speed 10 ! interface FastEthernet0/18 switchport access vlan 5 switchport mode access duplex full speed 100 ! interface FastEthernet0/19 switchport access vlan 5 switchport mode access duplex full speed 100 ! interface FastEthernet0/20 switchport mode trunk switchport nonegotiate duplex full speed 10 ! interface FastEthernet0/21 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/22 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/23 switchport access vlan 4 switchport mode access duplex full speed 100 ! interface FastEthernet0/24 switchport access vlan 6 switchport mode access ! interface Vlan1 ip address 192.168.1.3 255.255.255.0 no ip route-cache ! ip http server ! line con 0 transport input none line vty 0 4 password ---------- login line vty 5 15 password M---------- login ! end

SWITCH1#show interface trunk

Port Mode Encapsulation Status Native vlan Fa0/20 on 802.1q trunking 1

Port Vlans allowed on trunk Fa0/20 1-1005

Port Vlans allowed and active in management domain Fa0/20 1-5,99

Port Vlans in spanning tree forwarding state and not pruned Fa0/20 1-5,99

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SWITCH2#show running-config Building configuration...

Current configuration : 1346 bytes ! version 12.1 no service pad service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname SWITCH2 ! enable secret 5 ------------------- enable password ------------------- ! ip subnet-zero ! ! ! spanning-tree mode pvst no spanning-tree optimize bpdu transmission spanning-tree extend system-id no spanning-tree vlan 2-6 ! ! ! ! interface FastEthernet0/1 switchport mode trunk switchport nonegotiate speed 10 duplex full spanning-tree bpduguard disable ! interface FastEthernet0/2 switchport mode access speed 100 duplex full ! interface FastEthernet0/3 switchport mode access speed 100 duplex full ! interface FastEthernet0/4 switchport access vlan 2 switchport mode access duplex full speed 100 ! interface FastEthernet0/5 switchport access vlan 2 switchport mode access duplex full speed 100 ! interface FastEthernet0/6 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/7 switchport access vlan 3 switchport mode access duplex full speed 100 ! interface FastEthernet0/8 switchport access vlan 4 switchport mode access duplex full speed 100 ! interface FastEthernet0/9 switchport access vlan 4 switchport mode access duplex full speed 100 ! interface FastEthernet0/10 switchport access vlan 5 switchport mode access duplex full speed 100 ! interface FastEthernet0/11 switchport access vlan 5 switchport mode access duplex full speed 100 ! interface FastEthernet0/12 speed 100 duplex full ! interface Vlan1 ip address 192.168.1.2 255.255.255.0 no ip route-cache ! ip http server ! line con 0 line vty 0 4 password ---------- login line vty 5 15 password ---------- login ! ! end

SWITCH2#show interface trunk

Port Mode Encapsulation Status Native vlan Fa0/1 on 802.1q trunking 1

Port Vlans allowed on trunk Fa0/1 1-4094

Port Vlans allowed and active in management domain Fa0/1 1-5,99

Port Vlans in spanning tree forwarding state and not pruned

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BernieM 19 years ago

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Have you actually created the other vlans on the switches?

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Trendkill 19 years ago

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You need to run VTP. Second, you need to make sure that the VLANs are showing as up/up in show ip int brief. This will require either an interface that is up in those VLANs, or a configured layer 3 interface.

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John Tressle 19 years ago

I deleted all VLANS on switch2, configured switch1 as a VTP server and switch2 as a VTP client - both in the same VTP domain. I can see the VLANS have been transferred to switch2 and if I plug 2 devices into the same VLAN on switch2 (e.g. vlan2) they can ping each other. They still can't ping a device plugged into vlan2 on switch1 however. Devices patched into vlan1 only can ping each other across the link.

Is there anything else I'm missing here? - I'm at my wits end!

Many thanks, John

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Trendkill 19 years ago

paste configs again please. Along with show ip int brief, show int trunk, show spanning-tree vlan 1 and show spanning-tree vlan 2 on the switches.

What ip range is vlan 1 vs. 2?

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Brian V 19 years ago

what are you using to route the vlans? The 2950 is only a layer 2 switch, the vlans will never be able to talk to eachother without a layer 3 device.

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Smokey 19 years ago

You should be able to create vlans on 2 switches and communicate as long as the 2 devices are in the same vlan. you do not need a layer 3 device unless you are routing to a different vlan.

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BernieM 19 years ago

There's no specific requirement to run vtp at all. We run a network of

6500's, 3750's, 3560's and 2950's and do not use vtp. I'd steer away from the default values ie. instead of assuming "switchport trunk allowed vlan all" is active, actually configure what vlans you want trunked ... "switchport trunk allowed vlan ".

I'm curious as to why you have disabled spanning tree. If you're concerned about delays with ports becoming active just configure "spanning-tree portfast" on access ports. With spanning-tree enabled you'll be able to see the layer-2 topology using "show spanning-tree vlan ".

BernieM

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linkwood 19 years ago

Hi John,

why do you use 10Mbps for the trunk? I'm not shure whether 802.1q is running on 10Mbps.

If it doesn't help: send an overview, something like PC - fa0/1 - switchA - fa0/20 - fa0/1 - switchB - fa0/24 PC send also a "show cdp neigh" and of course the config (if you've allredy changed something)

lw

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John Tressle 19 years ago

Thanks for your help with this so far - it's really appreciated. The trunk ports are currently set to 10Mb because the link between the 2 switches is actually a leased line which is presented as 10Mb on both ends - should this make a difference?

The connection is not routed - up until this point we've been using the connection specifically for vlan1 traffic with devices on the same subnet (192.168.1.0/24) connected on both ends without a problem. We're implementing the trunk because we now need devices on the 2nd switch on other vlans (again no routing involved - devices within vlans on both switches are configured in the same subnet). To confirm - since implementing the trunk, devices on vlan1 can ping each other over the trunk - but no devices in other vlans will see each other. Spanning Tree is disabled because we had problems connecting our Internet connection (VLAN2 on switch

1) and were recommended to disable by the provider.

I've attached show interface trunk, the current vlans, show cdp neighbor and show ip interface brief:

Thanks again for your assistance, John

SWITCH1#show interface trunk

Port Mode Encapsulation Status Native vlan Fa0/20 on 802.1q trunking 1

Port Vlans allowed on trunk Fa0/20 1-1005

Port Vlans allowed and active in management domain Fa0/20 1-6,99

Port Vlans in spanning tree forwarding state and not pruned Fa0/20 1,6

SWITCH1#show cdp neigh Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater

Device ID Local Intrfce Holdtme Capability Platform Port ID SWITCH2 Fas 0/20 125 S I WS-C2950-1Fas 0/1 SWITCH3 Fas 0/18 172 S I WS-C2950-2Fas 0/20

SWITCH1 (vlan)#show current VLAN ISL Id: 1 Name: default Media Type: Ethernet VLAN 802.10 Id: 100001 State: Operational MTU: 1500

VLAN ISL Id: 2 Name: VLAN0002 Media Type: Ethernet VLAN 802.10 Id: 100002 State: Operational MTU: 1500

VLAN ISL Id: 3 Name: VLAN0003 Media Type: Ethernet VLAN 802.10 Id: 100003 State: Operational MTU: 1500

VLAN ISL Id: 4 Name: VLAN0004 Media Type: Ethernet VLAN 802.10 Id: 100004 State: Operational MTU: 1500

VLAN ISL Id: 5 Name: VLAN0005 Media Type: Ethernet VLAN 802.10 Id: 100005 State: Operational MTU: 1500

VLAN ISL Id: 6 Name: VLAN0006 Media Type: Ethernet VLAN 802.10 Id: 100006 State: Operational MTU: 1500

VLAN ISL Id: 99 Name: Autotest_Lab Media Type: Ethernet VLAN 802.10 Id: 100099 State: Operational MTU: 1500

VLAN ISL Id: 1002 Name: fddi-default Media Type: FDDI VLAN 802.10 Id: 101002 State: Operational MTU: 1500 Ring Number: 0

VLAN ISL Id: 1003 Name: token-ring-default Media Type: Token Ring VLAN 802.10 Id: 101003 State: Operational MTU: 1500 Ring Number: 0

VLAN ISL Id: 1004 Name: fddinet-default Media Type: FDDI Net VLAN 802.10 Id: 101004 State: Operational MTU: 1500 Bridge Number: 1 STP Type: IEEE

VLAN ISL Id: 1005 Name: trnet-default Media Type: Token Ring Net VLAN 802.10 Id: 101005 State: Operational MTU: 1500 STP Type: IBM

SWITCH1#show ip interface brief Interface IP-Address OK? Method Status Protocol Vlan1 192.168.1.3 YES NVRAM up up

FastEthernet0/1 unassigned YES unset up up

FastEthernet0/2 unassigned YES unset up up

FastEthernet0/3 unassigned YES unset up up

FastEthernet0/4 unassigned YES unset up up

FastEthernet0/5 unassigned YES unset up up

FastEthernet0/6 unassigned YES unset up down

FastEthernet0/7 unassigned YES unset up up

FastEthernet0/8 unassigned YES unset up up

FastEthernet0/9 unassigned YES unset up up

FastEthernet0/10 unassigned YES unset up up

FastEthernet0/11 unassigned YES unset up up

FastEthernet0/12 unassigned YES unset up up

FastEthernet0/13 unassigned YES unset up up

FastEthernet0/14 unassigned YES unset up up

FastEthernet0/15 unassigned YES unset up up

FastEthernet0/16 unassigned YES unset up up

FastEthernet0/17 unassigned YES unset up up

FastEthernet0/18 unassigned YES unset up up

FastEthernet0/19 unassigned YES unset up up

FastEthernet0/20 unassigned YES unset up up

FastEthernet0/21 unassigned YES unset up down

FastEthernet0/22 unassigned YES unset up down

FastEthernet0/23 unassigned YES unset up down

FastEthernet0/24 unassigned YES unset up down

SWITCH2#show interface trunk

Port Mode Encapsulation Status Native vlan Fa0/1 on 802.1q trunking 1

Port Vlans allowed on trunk Fa0/1 1-4094

Port Vlans allowed and active in management domain Fa0/1 1-6,99

Port Vlans in spanning tree forwarding state and not pruned Fa0/1 1-3,5-6

SWITCH2#show cdp neigh Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone

Device ID Local Intrfce Holdtme Capability Platform Port ID SWITCH1 Fas 0/1 155 S I WS-C2950-2Fas 0/20

SWITCH2(vlan)#show current VLAN ISL Id: 1 Name: default Media Type: Ethernet VLAN 802.10 Id: 100001 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 2 Name: VLAN0002 Media Type: Ethernet VLAN 802.10 Id: 100002 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 3 Name: VLAN0003 Media Type: Ethernet VLAN 802.10 Id: 100003 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 4 Name: VLAN0004 Media Type: Ethernet VLAN 802.10 Id: 100004 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 5 Name: VLAN0005 Media Type: Ethernet VLAN 802.10 Id: 100005 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 6 Name: VLAN0006 Media Type: Ethernet VLAN 802.10 Id: 100006 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 99 Name: Autotest_Lab Media Type: Ethernet VLAN 802.10 Id: 100099 State: Operational MTU: 1500 Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 1002 Name: fddi-default Media Type: FDDI VLAN 802.10 Id: 101002 State: Operational MTU: 1500 Bridge Type: SRB Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 1003 Name: token-ring-default Media Type: Token Ring VLAN 802.10 Id: 101003 State: Operational MTU: 1500 Bridge Type: SRB Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 1004 Name: fddinet-default Media Type: FDDI Net VLAN 802.10 Id: 101004 State: Operational MTU: 1500 Bridge Number: 1 STP Type: IEEE Backup CRF Mode: Disabled Remote SPAN VLAN: No

VLAN ISL Id: 1005 Name: trnet-default Media Type: Token Ring Net VLAN 802.10 Id: 101005 State: Operational MTU: 1500 Bridge Number: 1 STP Type: IBM Backup CRF Mode: Disabled Remote SPAN VLAN: No

SWITCH2#show ip int brief Interface IP-Address OK? Method Status Protocol Vlan1 192.168.1.2 YES manual up up

FastEthernet0/1 unassigned YES unset up up

FastEthernet0/2 unassigned YES unset up up

FastEthernet0/3 unassigned YES unset up up

FastEthernet0/4 unassigned YES unset up up

FastEthernet0/5 unassigned YES unset up up

FastEthernet0/6 unassigned YES unset up up

FastEthernet0/7 unassigned YES unset up up

FastEthernet0/8 unassigned YES unset up up

FastEthernet0/9 unassigned YES unset up up

FastEthernet0/10 unassigned YES unset up up

FastEthernet0/11 unassigned YES unset up up

FastEthernet0/12 unassigned YES unset up up

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Brian V 19 years ago

Obviously. I misread his statement, I thought he said devices within the same vlan could ping eachother but could not ping other vlans which would imply a layer 3 device is needed.

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BernieM 19 years ago

I think you'll find it's what makes the difference. Does your vendor support the trunking of 'non-default vlans'? ie. provide for the other vlans being trunked through their equipment.

BernieM

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Peter 19 years ago

Hi John,

What format is this "Leased Line" presented in, is it capable of passing data as a TRUNK or is it presented as a simple VLAN itself? If it is a simple VLAN, then it will only be capable of delivering the DEFAULT vlan for the switch, which is VLAN 1, as your TRUNK port will be treated as an ACCESS port by the WAN link. You could test this by changing the DEFAULT VLAN on the switch and see if that one is passed instead of VLAN 1.

Cheers.................pk.

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John Tressle 19 years ago

Guys - thanks for all your help with this. I've spoken with the provider of the leased line and that is indeed where the problem lies. Hopefully they'll be able to enable this on the line which should sort out my issue. Thanks again - you've saved my a great deal of time.

Cheers, John

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linkwood 19 years ago

Hi John,

I guess your provider somehow drops 802.1q tagged frames. (Since vlan1 is native it's not tagged and therefor it works) This could be due to the fact that the provider provides a vlan to you. So if this provider vlan should support transport of your vlans your provider needs to support Q-in-Q tagging.

Best way is to check this with your provider since as far as I can see your config should work.

Regards lw

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