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Cisco 3600 swith from T1 to fiber VLAN help

I am hoping someone can help me with this problem. Currently, I have an enterprise router, a Cisco 3600 that has four serial ports configured for T1 wan connections and Ethernet0/0 as the local LAN ethernet port (192.168.3.1) I am switching over from the T1 connections to fiber for the three of the four outside facilities. The fiber company pulled fiber and told me that they are now all configured in a VLAN. I have one ethernet cable that they are telling me that I just need to plug into the router. That's my problem. I don't know where to start. At first, I thought I could assign Ethernet0/1

192.168.3.2, plug the fiber into that and then add routing statements to tell it to get to 192.168.4.0, 5.0, and 6.0 to send the packet to 192.168.3.2. It wouldn't let me assign that IP to ethernet0/1. Strike 1. I then assigned 192.168.100.1 to ethernet0/1 and then added ip route 192.168.4.0 255.255.255.0 192.168.100.1, but it told me I couldn't add the route because the 100.1 interface is the same router. I also couldn't even ping 192.168.100.1 while telnetted to the router. Strike 2. Am I even thinking about this correctly? I am assuming I need to address Ethernet0/1, give it an IP address, plug in the ehternet cable to the fiber vlan, and then add routing statements to network id's in the VLAN so they go over Ethernet0/1 and not Ethernet0/0.

I hope my explanation isn't too confusing.

Reply to
Steve
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so they combined your 4 t1's into one fiber run?? and handed off a cat5 (ethernet) cable to you? and in this ethernet cable are your previous 4 T1 connections in seperate vlans?? if this is the case, you need to configure subinterfaces on the routers ethernet interface...you will need at least two things from your service provider - the vlan numbers and the encapsulation type. on each subinterface you need to configure the encapsulation type and vlan, and the ip address. eg>

conf t int eth 0/1 no ip address int eth0/1.100 encapsulation dot1q 100 (the 100 here is the isp assigned vlan) ip address 192.168.x.y 255.255.255.0 int eth0/1.200 encapsulation dot1q 200 (the 200 here is the isp assigned vlan) ip address 192.168.x.z 255.255.255.0

you get the picture? the subinterface number is arbitrary but best practice is to assign it the same number as the vlan. if this isn't what the isp was telling you, then i didn't understand your problem.

Reply to
john smith

Thanks for the reply, John.

The ISP ran fiber to the facilities, and combined them into just 1 VLAN. Each facility has a fiber box and an existing Cisco 3600 router. Would your configuration example still apply if it is just one VLAN? The ISP made it sound like it was plug and play, but they don't support anything past their equipment, namely helping configure the Cisco router.

The current setup: The enterprise hub router (Cisco 3600) has a private IP of 192.168.3.1 assigned to Ethernet0/0. The other sites have 192.168.4.1,

192.168.5.1, and 192.168.2.1 assigned to their Ethernet0/0 interfaces and they all connect to the router at 192.168.3.1 as the hub in a hub and spoke topology. The outer sites connect to the hub 3600 router via T1. The 3600 has csu/dsus connected to serial 0 1 2 3 for the outer sites. I am removing the csus and I want to use Ethernet0/1 to connect to the single fiber VLAN. I am just unclear of (1) how to address Ethernet0/0 on the router and (2) how to tell the router to use Ethernet0/1 to get to 192.168.4.0, 5.0 and 2.0. I know I will have to repeat the config on the routers at the other sites so the VLAN is completely used.

Sorry if my explanation is unclear.

Reply to
Steve

Sorry, I meant to ask: .

Reply to
Steve

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