RE: Simple route/gateway forwarding
James Smallacombe <[email protected]> Mon, 5 Apr 2010 14:59:42 -0400 (EDT)
| Newsgroups | gmane.org.operators.internet-access |
|---|---|
| Message-ID | <[email protected]> |
On Mon, 5 Apr 2010, Brian Johnson wrote: > What you are trying to do is definitely possible. How you are stating > this makes my head hurt. :) Sorry...I can see how it looks super-complex, but in reality, it's not too bad. > You have a LAN using the 192.168.7.0/24 network. This network has two Actually, it's using 192.168.0.0/21. Nothing in there is actually subnetted out, although, for example, 192.168.7.x is set aside for network equipment and 192.168.3.x is set aside for workstations, etc. > externally facing routers and one internally facing router. The > internally facing router uses NAP (do you mean PAT, overloaded NAT?) and Yes, like most NAT implementations like this, it is overloaded, not 1-to-1. > uses the 192.168.0.0/21 network internally. > > +------------+ +------------+ > | Provider A | | Provider B | > +------------+ +------------+ > | | > +-----------+ +-----------+ > | CPE-RTR A | | CPE-RTR B | > +-----------+ +-----------+ > 192.168.7.1/24 \ / 192.168.7.10/24 > \ / In the case of provider A, there is no customer access to their CPE router and it is not doing NAT. NAT is being performed by the customer's 2811. RFC 1918 to the internal Ether and provider A's "real" /26 on the external Ether. Provider B's Netgear is on the same LAN as the 2811's internal Ether and performing NAT to B's upstream network. We DO have access to this B's Netgear. I gave it 192.168.7.10/21 while the 2811 bas 192.168.7.1/21. > +------------+ > | LAN SWITCH | > +------------+ > | > | 192.168.7.2/24 > +----------+ / ip route 0.0.0.0 0.0.0.0 > 192.168.7.1 This is a little off. 192.168.7.1/21 is on the 2811's internal Etherm while a real IP is on the external interface. The Cisco has ip route 0.0.0.0 0.0.0.0 real.ip.of.A's.CPE.router > | 2811 RTR | NAT/PAT <--< ip route 192.168.3.240 > 255.255.255.255 192.168.7.10 > +----------+ \ That looks correct, above. > | 192.168.0.1/21 You mean the 192.168.0.0/21 network above, right? > If this diagram is correct, and the CPE routers are configured > correctly, then packets bound for 192.168.3.240 WILL be forwarded to > 192.168.7.10. What that router does with it is another question all > together. > > Do you have access to the CPE routers? Are you using a routing protocol > or just static routes? You are dealing with all private IP addresses in > your example. Are they really all private IP addresses or are there some > public addresses in here? Just static routes. Want to avoid RIP and the Netgear doesn't do OSPF. > - Brian > >> -----Original Message----- >> From: [email protected] [mailto:list-bounces@inet- >> access.net] On Behalf Of James Smallacombe >> Sent: Monday, April 05, 2010 9:33 AM >> To: Inet-Access Mailing List >> Subject: Simple route/gateway forwarding >> >> >> This is really basic, but since I've never tried it before (and it's >> not >> working), I want to see if it's possible, one way or another: >> >> customer has a network hooked up to provider A using provider's CPE >> router. They also have a 2811 doing NAT, which is the default gateway >> for >> the NAT'd network 192.168.0.0/21. The 2811 then has a default route > to >> the CPE router and a typical "internal" Ethernet on 192.168.7.1 and an >> "external" Ethernet on Provider A's static IPs. >> >> To this, they add a second connection, a business broadband connection >> using a typical broadband router (NetGear, I believe) to provider B. >> They know their provider A static IPs, won't route through provider > B's >> network, but certainly the NATed 192.168. network will. I stick the >> Netgear on the same Ether as the 2811's internal interface and give it >> 192.168.7.10. All workstations use a default gateway of 192.168.7.1. >> The >> idea is to be able to switch them over to 192.168.7.10 without having >> to >> change their settings, by just re-routing some networks on the Cisco > to >> provider B. I tried this as a test: >> >> ip route 192.168.3.240 255.255.255.255 192.168.7.10 >> >> Similar to a ppp /32 route. However, all traffic from 192.168.3.240 >> still >> goes out the default route to provider A via the default route. Is >> there >> a way to make this work without subnetting 192.168.3.0 and putting >> aliases >> of it on one or both routers? >> >> James Smallacombe PlantageNet, Inc. CEO and Janitor >> [email protected] > http://3.am >> > ======================================================================= >> == >> -- >> Eat sushi frequently. - Avi >> [email protected] is the human contact address. >> [email protected] is the list posting address. >> See below URL for subscribe/unsubscribe and list options: >> http://inet-access.net/mailman/listinfo/list > > CONFIDENTIALITY NOTICE: This email message, including any attachments, is for the sole use of the > intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, > copying, use, disclosure, or distribution is prohibited. If you are not the intended recipient, please > contact the sender by reply e-mail and destroy all copies of the original message. Thank you. > -- > Eat sushi frequently. - Avi > [email protected] is the human contact address. > [email protected] is the list posting address. > See below URL for subscribe/unsubscribe and list options: > http://inet-access.net/mailman/listinfo/list > James Smallacombe PlantageNet, Inc. CEO and Janitor [email protected] http://3.am ========================================================================= -- Eat sushi frequently. - Avi [email protected] is the human contact address. [email protected] is the list posting address. See below URL for subscribe/unsubscribe and list options: http://inet-access.net/mailman/listinfo/list