We help IT Professionals succeed at work.

Multi-Home problem

ssbn628
ssbn628 asked
on
304 Views
Last Modified: 2013-11-09
We have two routers one a Cisco 2621xl provided by us with an ATM connection with one provider. AT$T has a router there as a second T1 line. I would like to route traffic from two wirreless subnets 12.2.15.0/24 and 10.10.0.0/24 to the AT&T router. Both of these routers are plugegd directly into a Cisco 2950 switch as well as the wireless links providing connection to the above subnets. We are only using static routing (something I inherited) At present I have the gateway addresses for these two subnets set up on the FE ports of our Cisco 2621,being 10.2.15.1 and 10.10.0.1, My question is can I just get AT&T (managed router) to assign 10.1.0.1 and 10.2.15.1 to their FE ports on their router and me change mine to another ip address,and make this work?
Comment
Watch Question

mikecrIT Architect/Technology Delivery Manager
CERTIFIED EXPERT

Commented:
I'm not sure I understand. Can you draw a small diagram how it looks now? i.e.,
Router--------switch---------LAN
This one is on us!
(Get your first solution completely free - no credit card required)
UNLOCK SOLUTION
CERTIFIED EXPERT
Most Valuable Expert 2015
Commented:
This one is on us!
(Get your first solution completely free - no credit card required)
UNLOCK SOLUTION
It looks like he actually has two separate interfaces on the 2621, one for each subnet.  So in order for this to work the AT&T router would need either an interface in each subnet or use secondary IP addressing and then he could do two route maps, one for each subnet.

or

If the AT&T router does have an IP address for each subnet, either through separate interfaces or using secondary IP addressing, he could even change the default gateway on the clients that are hanging off the wireless to point to the AT&T router addresses.  Of course this would only be a viable/easy solution if you are using DHCP for the wireless clients.

Author

Commented:
Thanks for the replys. I'll try and clear this up. Both routers (ours with a T1 line providded by a provider) and the AT$T Managed router with a T1 line. At present we are not able to use both T1 lines. I want to just take the traffic from two wireless access points 10.2.15.0/24 and 10.10.0/24 and have them go to the AT$T managed router. We have other subnets on our router that will use the existing T1 line in ourr Cisco router. Both of these routers are plugged into a Cisco 2950 switch(all FE ports). If AT&T will put their FE ports on 10.10.0.1 (gateway for 10.10.0.0/24) and 10.2.15.1 (Gateway for 10.2.15.0/24) will my customers be able to surf through the AT&T router provided I change my IP addresses now on my router (10.10.0.1 and 10.2.15.1, 9these are secondary addresses) and still be able to get to my customers antennas? I hope this made sense. We don't know much about routing but are having to learn in a hurry.
mikecrIT Architect/Technology Delivery Manager
CERTIFIED EXPERT

Commented:
Do those wireless subnets overlap anything on the network? If so you won't be able to send them out that T1 easily. Do you know what the inside IP is of the managed router from AT&T? You should be providing a next hop somewhere to it? Do your access points lay behind a firewall or on the same switch as the routers? If they are on the same switch as the routers, you can change their gateway to the inside of the AT&T router.

Author

Commented:
I think I will try the route map idea. AT&T put 10.10.0.3 and 10.2.15.2 on their interfaces. I can ping the 10.10.0.3, but not the 10.2.15.2. Anyway if I can get to one it should work. I have a question in the above example by jesper. Do I put the 80 before the permit? I don't know much about routers. But on the access list do I put  access-list permit IP 80 10.2.15.0 0.0.0.255 or access-list 80 permit 10.2.15.0.0.0.0.255? I sure appreciate the help.
CERTIFIED EXPERT
Most Valuable Expert 2015

Commented:
Um, yes. :(

access-list 80 permit ip 10.2.15.0 0.0.0.255

Author

Commented:
Thanks jesper..I'll try this and let you know what happened.

Author

Commented:
Jesper, Can I just do this in the global configuration mode without policy routing and all that? I know enough how to do just the global configuration stuff. Policy routing is out of my league! :-(
No there is no other way to do it at the router.

What you can do is change the default gateway of the clients on the wireless networks.

Are you using DHCP on these networks?
CERTIFIED EXPERT
Most Valuable Expert 2015

Commented:
Agreed.

1) Change the default-gateway
2) Use Policy Based Routing
     Place the route-map to incoming traffic from the local area network

Author

Commented:
I wish it were DHCP, the customer location involves a truck roll out about 50 miles away..then we would have to go to each customer's home. Lousy setup. I just inherited this mess..now they want me to make it worl. I guess I could change my default route to make it go through the AT&T router,but that isn't really a solution just a way to at least use what we paid for. AT&T told us they could make it work.Just don't ever get a managed router!!
To make it easier for yourself create a DHCP pool on the router and they you just have to tell the customers to change to DHCP.  Those who have no idea how to do this are the only ones you will have to visit.  I will put the config for one pool then you can just reproduce it for the other network.

From global config
ip dhcp pool [name of the pool 1]
   network 10.10.0.0 255.255.255.0 (or whatever the mask is)
   default-router 10.10.0.3
   dns-server x.x.x.x (insert IP address of the DNS servers.  You can find this in the static configuration of one ot the client workstations on the wireless)
   domain-name whatever.com

The from global config mode again you can configure your exclusion range (addresses you do not want handed out by DHCP)

ip dhcp ip dhcp excluded-address 10.10.0.1 10.10.0.20 (that is the starting and ending address 1 to 20 for example.

Let me know if you need any further assistance with this.
Unlock the solution to this question.
Join our community and discover your potential

Experts Exchange is the only place where you can interact directly with leading experts in the technology field. Become a member today and access the collective knowledge of thousands of technology experts.

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

OR

Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.