Want to route multiple VLAN's across data PtP - 1921?

ADynes · ‎03-30-2012

We currently have two 7+ year old AdTran 3205 routers between two of our offices doing pure data point to point functions. Our company has grown and we are running out of space on our subnets so we have decided to properly split up the network into multiple VLAN's with different subnets: users, servers and infrastructure, and phones (no VoIP over the PtP, jsut data). We attempted to get the AdTran's to encapsulate 802.1 data but after hours of fustration we gave up. Will the 1921's do this easily? Our setup will look like this when done:

          ISP 1                                      ISP 2
            |                                          |
            |                                          |
            |                                          |
            | 10.1.0.0/24                              | 10.2.0.0/24
            |                 10.0.0.0/30              |
    Layer-3 Switch 1 -- 1921-1 --------- 1921-2 -- Layer-3 Switch 2
    |      |       | .1                        .2  |      |       |
    |    LAN 2     |                               |    LAN 2     |
    | 10.1.20.0/24 |                               | 10.2.20.0/24 |
    |              |                               |              |
   LAN 1          LAN 3                           LAN 1          LAN 3
10.1.10.0/24   10.1.30.0/24                   10.2.10.0/24    10.2.30.0/24
  
       Building #1                                    Building #2

There are multiple switches at each end but one Layer 3 that would be connected to the 1921. The Layer 3 switches will also do the routing, the 1921's will simply act as the point to point routers across a T1 (possibly in the future a dual/bonded T1). Unless it makes sense to give the routers 3 IP addresses each and have them do the routing.

Thoughts?

-Allan

Jeff Van Houten · ‎03-31-2012

I'm not sure the Adtrans wouldn't work. If the layer 3 switches are doing the routing for the internal subnets, then why does the router need to do .1q encapsulation at all? Couldn't you just setup a simple /30 between the router and a routed port on the switch (no switch port)?

Sent from Cisco Technical Support iPad App

ADynes · ‎03-31-2012

The exact setup listed above did NOT work with the AdTrans and after some research online it was because you have to enable .1q encapsulation for the AdTrans to route the tagged VLAN data betwee routers. So we tried that but as I said we couldn't get the AdTrans to work after many hours of trying even though they "should" have worked.

The interconnect between the switches and the routers on both ends will be on Trunk ports so that something on VLAN10 in one office will still be VLAN10 in the other office. On the AdTrans the traffic simply didn't go across. On our Cisco 1300 wireless bridges it didn't at first until we defined VLAN10 then that traffic traveled across the bridges. Are you saying as long as I define VLAN10, 20, 30, and 40 on these Cisco 1921's I won't have to setup anything else...the data will go between teh rotuers over the PtP T1 without any other setup?

Note: we also need QoS for one of the VLAN's as it will carry data between phone systems. It's "data" not voice traffic but it still needs a higher priority.

-Allan

thomas.satafer.fan · ‎03-31-2012

Routers may have only very limited switch functions. So it may not possible to turn your 1921 into a normal trunked switching device.

To solve the issue in a routed environment, which is 1921's nature, you could enable proxy ARP in two 1921s. A l2tp maybe a better solution if your 1921 is capable.

,

ADynes · ‎04-01-2012

I don't understand how l2tp plays into this.

All I need to know is if the 1921's can carry VLAN data over a T1 PtP easily. If not I need another solutionas the current AdTrans do not.

ADynes · ‎04-09-2012

I talked to my CDW rep and they said wha tI want ot do "should work" but I really would like a Cisco perosn to confirm. Is what I'm doing that out of the normal? Will what I want work? I jsut want the different tagged VLAN's to route over the point to point.

-Allan