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Linking two sites core to core

david-swope
Level 1
Level 1

I have a design I am looking at putting together for a customer. There are two sites involved, AT&T has handed off Ethernet to me at my main site for a 100MB Opt-E-Man circuit.

They want to use this for DR to their other site. I was thinking going core->core to acheive this. AT&T has advised me of their vlan and to trunk to them

I have one vlan at each site that needs to pass over this 100MB circuit.

Main Site

VLAN 100 - 192.168.100.0/24

Site B

VLAN 200 - 192.168.200.0/24

How would you go about achieving this?

6 Replies 6

rfalconer.sffcu
Level 3
Level 3

As the simplest answer, set up a L3 link between them and let your routing protocol handle it.

But there are some other basic considerations as well. Are there other subnets at each site that shouldn't pass over this link? How does your routing work now? Can those switches handle any QoS that you want to use?

AT&T handed off ethernet and provided the VLAN ID (1580). If this is L2 then it's easy

Main Site - Core

int vlan 1580

ip address 192.168.1.1 255.255.255.240

int g0/52

switchport trunk encapsulation dot1q

switchport mode trunk

switchport trunk allowed vlan 100,1581

Site B - Core

int vlan 1580

ip address 192.168.1.2 255.255.255.240

int g0/52

switchport trunk encapsulation dot1q

switchport mode trunk

switchport trunk allowed vlan 200,1580

At this point I need more information, if this is L2 then I need a handoff at both sites...otherwise they need to provide me with public IP's for L3 routing yeah?

Has AT&T not given you a handoff at Site B?

A lot of this is my fault, it was all last minute today and I didn't get enough information from the customer. Guess it will be tomorrow but I think I have a handle on it now..I stepped back and thought about it and it makes sense, if it is truly L2 then AT&T would have to handoff at Site B, otherwise I need to get IP's from them then I will use EIGRP to route the appropirate traffic across.

There is probably a hand-off at the other side and you can just do it as you've shown above, with vlan 1580.

Confirmed L2, configured it no problem...

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