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Creating a trunk between two 2950s

This should be an easy "red-meat" question for this group.

I was asked to set up a trunk between two 2950 switches. When I configured the two switches (via a Windows VPN connection, via Remote Desktop, via a telnet connection), once the interfaces came up, I lose my connection. A person onsite would disconnect the cable between the switches and I was able to get back in. I will post the original running configs below of the two switches so that you can see how it was initially set up (before trying to set up the trunking). Note that I did not do the initial configuration of these switches and this is the first time I have laid eyes on them, so I am wondering if there is something in these configurations that is causing the issue. If anyone could let me know what modifications might be made to clear up this issue that would be much appreciated. BTW -- Port 24 on both switches are the ones that are currently connected and thus the ones that will need to be changed to trunk mode.

Thanks in advance for any help offered

MTD

Swirtch #1: sh ru Building configuration...

Current configuration : 4195 bytes ! version 12.1 no service pad service timestamps debug datetime service timestamps log datetime service password-encryption ! hostname Catalyst_1 ! enable secret 5 $1$6Cr0$w6SznsoXQVCTDsG3Kn5WU. ! ip subnet-zero ! vtp domain synsw1 vtp mode transparent ! ! spanning-tree mode pvst no spanning-tree optimize bpdu transmission spanning-tree extend system-id spanning-tree vlan 1 priority 49152 no spanning-tree vlan 701 spanning-tree vlan 701 priority 4096 no spanning-tree vlan 702 spanning-tree vlan 702 priority 49152 spanning-tree vlan 999 priority 49152 ! ! vlan 701 name Outside ! vlan 702 name joeblow ! vlan 999 name black state suspend ! interface FastEthernet0/1 description LB2-1 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/2 description LB1-1 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/3 description ProStructure Monitoring Server switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/4 description firewall-3 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/5 description inflow port for monitoring switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/6 description monitoring port switchport access vlan 701 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/7 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/8 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/9 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/10 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/11 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/12 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/13 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/14 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/15 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/16 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/17 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/18 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/19 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/20 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/21 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/22 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/23 switchport access vlan 999 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/24 description sw1:fa0/24 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 ! interface Vlan1 ip address 1.1.1.10 255.255.255.0 no ip route-cache shutdown ! interface Vlan2 no ip address no ip route-cache shutdown ! interface Vlan702 ip address 10.11.12.146 255.255.255.0 no ip route-cache ! no ip http server ! ! line con 0 exec-timeout 5 0 password 7 083255400D1C091B login line vty 0 4 exec-timeout 5 0 password 7 111A000B13170700 login line vty 5 15 exec-timeout 5 0 password 7 120A1C19160E0008 login ! end

Catalyst_1#

Switch #2:

sh ru Building configuration...

Current configuration : 4362 bytes ! version 12.1 no service pad service timestamps debug datetime service timestamps log datetime service password-encryption ! hostname Catalyst_2 ! enable secret 5 $1$QpdK$WIVRCX3T/o20YdzHwHPrw. ! ip subnet-zero ! ! ! spanning-tree mode pvst no spanning-tree optimize bpdu transmission spanning-tree extend system-id no spanning-tree vlan 701 spanning-tree vlan 701 priority 8192 no spanning-tree vlan 702 spanning-tree vlan 702 priority 8192 spanning-tree vlan 999 priority 53248 ! ! interface FastEthernet0/1 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/2 description monitoring port switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/3 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/4 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/5 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/6 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/7 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/8 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/9 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/10 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/11 switchport access vlan 701 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/12 description SunGard connection to monitor net switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/13 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/14 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/15 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/16 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/17 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/18 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/19 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/20 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/21 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/22 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 no cdp enable ! interface FastEthernet0/23 description prostructure-monitoring switchport access vlan 702 switchport mode access no ip address duplex full speed 100 ! interface FastEthernet0/24 description sw1:fa0/24 switchport access vlan 702 switchport mode access no ip address duplex full speed 100 ! interface Vlan1 no ip address no ip route-cache shutdown ! interface Vlan2 no ip address no ip route-cache shutdown ! interface Vlan702 ip address 10.11.12.145 255.255.255.0 no ip route-cache ! no ip http server ! ! line con 0 exec-timeout 5 0 password 7 105D101701121E07 login line vty 0 4 exec-timeout 5 0 password 7 105D101701121E07 login line vty 5 15 exec-timeout 5 0 password 7 02151D550F03032D login ! ! monitor session 1 source interface Fa0/5 - 8 , Fa0/17 - 18 monitor session 1 destination interface Fa0/23 end

Catalyst_2#

Reply to
MTD
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Hi,

interface FastEthernet0/24 switchport trunk encapsulation isl (or dot1q as you decide) switchport mode trunk

these are the basic config commands, if there are only is only one trunk link this will do. in any other case you should configure the spanning tree

good luck

andreas

awurf (AT) gmx(dot)de

Reply to
DruideDerNacht

Thanks for the response. That is how I did configure port 24 on both switches. It is once I completed configuring the second one and the port comes back online that I appear to lose connectivity. That is why I am thinking there may be something in the switches' current configuration that is causing the issue. Can anyone tell from the configs above whether there may be an issue with how the spanning tree protocol or the VLAN interfaces (or anything else) were originally configured? I am not familiar enough to know if something there is causing this issue. Thanks.

Reply to
MTD

reason why you loose connection, also with the above: The vlan On sw-1 the only port i vlan 702 which is the management vlan is the port you are configureing to trunk port. There must allway bee one port active in that vlan else the SVI doesnt get up.

HTH Martin

Reply to
Martin Bilgrav

Hi, the reason might be different VTP domains. the vtp configuration depends on the ios release. there are significant changes in the way of configuring vtp

former vtp database....

try to set both switches to

vtp domain synsw1 no vtp mode transparent

good luck

andreas

Reply to
DruideDerNacht

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