IP Route

[amitsonik]

I have 2 static routes been configured Router_A:

Router_A (Configuration)

ip route 0.0.0.0 0.0.0.0 10.0.1.1 // This is

the ISP Address(Configured on Ethernet 1)

ip route 10.0.0.128 255.255.255.128 Serial1 // This

is the route to Router_B which is in my office on

Router_A

Interface configuration on Router_A

int e1 //(This connected to a switch which is connected to ISP's ethernet port where ISP has configured 10.0.1.1 on one of the sub-interfaces)

ip address 10.0.1.2 255.255.255.128

media-type 10baseT

int s1

ip unnumbered ethernet1

encap ppp

no ip directed broadcast

Router_B (COnfiguration)

a)ip route 0.0.0.0 0.0.0.0 Serial0 //This is the route on Router_B which is connected through the T1 loop to Router_A in my office

Interface configuration on Router_B network:

int e0

ip address 10.0.1.129 255.255.255.128

media-type 10BaseT

no ip directed-broadcast

int s0

ip unnumbered ethernet0

encap ppp

no ip directed-broadcast

The problem that I get is, I can ping 10.0.1.1/25 but I cannot ping on any other network address.

I have just used this IP address for reference. Though all the addresses are public addresses.

I will appreciate if anyone can tell what is that i am doing wrong, or if I need my ISP to do something.

Thanks

Amit

[cybrgenx]

firstly I agree with Scott (svermill) remove the "ip route 0.0.0.0 0.0.0.0 207.97.177.1" and "ip route 207.97.177.129 255.255.255.255 Serial1", as this config will only route all ip packets to 207.97.177.1 unless it's 207.97.177.129! and since I see no reference to the .1 address anywher, its redundant to this configuration!

then add "ip route 207.97.177.128 255.255.255.128 serial1" this will route anything on the .0 network destined for the .128 network (e.g. 207.97.177.129 255.255.255.128) to the .128 network.

then add ip route 10.0.0.0 255.255.255.0 serial1 so the colo router will know how to get to the 10.0.0.0 network.

[amitsonik]

I would like to thank you for your interest.

The ip route 207.97.177.129 255.255.255.128 Serial1 was just added to troubleshoot the problem. In actual the route is "ip route 207.97.177.128 255.255.255.128 Serial1". If I will remove "ip route 0.0.0.0 0.0.0.0 207.97.177.1" then how will the colo router know where is the default route to get out to the public network. As you know that ISP's Router and Colo Router is connected to each other through a ethernet switch. So that was the reason that I had put this command in. Do you still feel that I need to change this entry.

Amit Sonik

[cybrgenx]

this may come thru twice, a hitch in my browser!

Ahh. now I understand!

to the colo router

leave the "ip route 0.0.0.0 0.0.0.0 207.97.177.1" (that is if it is directly attached to this router as I can't see the interface that it's attached to!)

remove "ip route 207.97.177.129 255.255.255.255 serial1"

add "ip route 207.97.177.128 255.255.255.128 Serial1"

this should work from you routers ;)

as for the 10.0.0.0 255.255.255.0 network to access the ISP public network you'll need to NAT. ISP's don't route public ip address'.

you'll have to NAT at your office router as NAT support didn't exsist until IOS version 11.2

[amitsonik]

Somebody has asked to me make 207.97.177.2 as the default gateway, I don't understand that. I mean their a ethernet switch which is connected to ethernet 1 on my colo router, then I have ISP's router connected to the same ethernet switch.

What the person also mentioned was that all the packets should route through 207.97.177.2 to the outside work. This is confusing for me. Can you make anything out of this..

[cybrgenx]

Ok, I think I may have it...

your gateway to the ISP is Ethernet1 207.97.177.2, they have a router attached to yours with the ip address 207.97.177.1.

all IP packets destined for the internet needs to be routed via 207.97.177.2 to 207.97.177.1! (ip route 0.0.0.0 0.0.0.0 207.97.177.1).

all packets destined for 207.97.177.128 255.255.255.0 network needs to be directed to interface serial 1 (ip route 207.97.177.128 255.255.255.128 Serial1).

this is all the ip route entries needed for the colo router.

The office router needs NAT configured (I will assume the ISP gave you the 207.97.177.128 255.255.255.0 network so you can use it to access the internet).

so all ip packet not destined for the local network needs to be routed to the colo router so it can forward the packets to the ISP router (ip route 0.0.0.0 0.0.0.0 serial0)

so the ISP route sees a IP packet it can route NAT needs to be configured.

IMPORTANT: Confirm with your ISP that you can use the range 207.97.177.130 - 207.97.177.254 for Network Address Translation!

interface Ethernet0

description connected to public network

ip address 207.97.177.129 255.255.255.128

ip nat outside

media-type 10BaseT

!

interface Ethernet1

description local network segment

ip address 10.0.0.1 255.255.255.0

ip nat inside

media-type 10BaseT

!

interface Serial0

description connected to colo

ip unnumbered Ethernet0

ip nat outside

ip nat pool nat-pool 207.97.177.130 207.97.177.254 netmask 255.255.255.128 type rotary

ip route 0.0.0.0 0.0.0.0 serial0

IMPORTANT: Confirm with your ISP that you can use the range 207.97.177.130 - 207.97.177.254 for Network Address Translation!

[svermill]

David,

I think that Amit now has the routes in place exactly as you describe. But I think that at his office router, the serial interface points to the colo router - which is attached to the ISP. Behind the office router are two ethernet interfaces. One on the ISP address space and one on a private address space. Amit has not indicated that hosts on the private subnet will require internet access. He is trying to ping the ISP router from his .129 segment at the office. But he is having trouble with the office to colo T1, so his ping tests are via a temporary collection of CSUs and routers that will not be the final setup.

Amit - is this correct?

[amitsonik]

Right. But since I have 2 ethernet interfaces behind my office router, I am having one ethernet port for the public addresses and the other ethernet interface for private network. The private network will also be using the internet.

But trouble is making the equipement speak to each other on the new T1 loop.

The other T1 loop is there, I just used it after work to troubleshoot the problem.