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ManuelFlag for United States of America

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URGENT CANNOT CONNECT TO A SWITCH THROUGH ROUTER

Hello,

   Here is the situation. There is a 3500 switch which has all ports on VLAN 1 by default. Connected to the 3500 switch is RouterB. RouterB Ethernet interface is 10.1.1.10 located on VLAN 1 of the 3500 Switch. Connected to RouterB serial interface is RouterA. The serial interfaces are using 5.0.2.2 and 5.0.2.1 respectively. Connected to RouterA Ethernet interface is a 2950 Switch. This switch is also connected back into the 3500 using ports 7 and 11 on the 2950 Switch for redundancy. Ports 7 and 11 are on VLAN 1 which all ports on the 3500 switch also are. RouterA is connected to port 3 which is on Vlan 23 that is located on the 2950 Switch. Between the routers EIGRP with PPP encapsulation is configured. My problem is that if I am connected to RouterB I am able to ping and ssh into the 2950 Switch. However, if I am on RouterA and I try to ping or ssh into the 2950 Switch, I am not able to. RouterA has a route to get to the 10.1.1.0 network. So what could I be doing wrong.

                  Thank You in Advance,
                 Victor
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Don Johnston
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I think I understand your topology, but could you provide some type of diagram?

What is the IP address of the ethernet interface on Router A?

What VLAN interface is used formanagement on the 2950 and what is the IP address of that interface?
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ASKER

Thank You for the fast response.

 Please go to www.virgoletta.com where you will find the diagram of the network.

                Thank You,
                Victor
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Don Johnston
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Shouldn't the default gateway be 80.1.1.1 for the 2950 Switch. If not can you please explain why.

              Thank You,
             Victor
A devices default gateway MUST be on the same network as the device. Since the IP address of the 2950 is 10.1.1.12/24, it's default gateway would have to be a router on the 10.1.1.0 network. The only router that meets this requirement is 10.1.1.10

Does this help?
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The only reason why I ask is because I tried 80.1.1.1 as the default gateway and I got the same results as when I was using 10.1.1.10 as the default gateway. The 2950 switch as two vlans one in the 10.1.1.0 network (VLAN 1) and the other is 80.1.1.0 network (VLAN 23). So that is why I am thinking I can use 80.1.1.1 as the default gateway?


                                Thank You
The 2950 cannot have more than one active VLAN interface at a time.

Please post the output of a "show ip int brief".
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Do you have an idea why I was able to use 80.1.1.1 as the default gateway and still get the same results as if I was using 10.1.1.10 as the default gateway? I see that Vlan 1 only shows but not Vlan 23.

                          Thank You

LabSwitch#sh ip int brief
Interface                  IP-Address      OK? Method Status                Protocol
Vlan1                      10.1.1.12       YES NVRAM  up                    up
FastEthernet0/1            unassigned      YES unset  down                  down
FastEthernet0/2            unassigned      YES unset  down                  down
FastEthernet0/3            unassigned      YES unset  up                    up
FastEthernet0/4            unassigned      YES unset  down                  down
FastEthernet0/5            unassigned      YES unset  down                  down
FastEthernet0/6            unassigned      YES unset  down                  down
FastEthernet0/7            unassigned      YES unset  up                    up
FastEthernet0/8            unassigned      YES unset  down                  down
FastEthernet0/9            unassigned      YES unset  down                  down
FastEthernet0/10           unassigned      YES unset  down                  down
FastEthernet0/11           unassigned      YES unset  up                    up
FastEthernet0/12           unassigned      YES unset  down                  down
LabSwitch#


The correct gateway for the 2950 is 10.1.1.10. After you have configured this, make sure you can ping that address from the 2950. If you can, try to ping 5.0.2.2 from the 2950. If you can ping the 10.1.1.10 address but not the 5.0.2.2 address the problem is with Router B.

Setting the default gateway to anything else will not allow you to communicate with anything on another network.

The reason you don't see VLAN 23 is that the "show ip int brief" shows VLAN interfaces. Not the VLAN's themselves.
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ASKER

I understand now, I pinged 10.1.1.10 from the 2950 and it worked. I also pinged 5.0.2.2 from the 2950 and it worked. So looks like everything is working well. Thank You for your help.


                       Thanks again.