Cannot ping after giving natting also.

[deypuchka]

Hello guys,

I have this configuration where my core switch (multilayer switch)is both doing routing and switching process.
My configurations which I have mention in the picture is all working, I can ping to the ISP Router (192.168.1.1)
but i cannot ping to the core switch (192.168.1.2) from the Remote Office. My ISP Router also can ping to 192.168.1.2.
Can someone please give solution where did i make a mistake out here. And if you want the configuration of the ISP router I do not have any except the default route.

ISP Router - ip route 0.0.0.0 0.0.0.0 192.168.1.2

[Georg Pauwen]

Hello,

what is the Remote Office, a router ? Post the full running configs of the core switch, as well as the device that is running at the Remote Office.

[deypuchka]

Yes and it runs with ip 172.16.1.1

[paul driver]

Hello

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@deypuchka wrote:

Hello guys,

ISP Router - ip route 0.0.0.0 0.0.0.0 192.168.1.2

In your diagram you show the core switch with a default static route pointing to the ISP rtr and then in your post you show a default static route pointing to the core switch!

The isp rtr should not have a default route pointing to the core switch if any it should be pointing egress towards the ISP network, plus what type of core switch are you running that supports NAT?

[MHM Cisco World]

this issue is from 
1- asymmetric routing the remote send traffic to Core and Core reply via ISP 
2- the NAT where even when asymmetric routing the ping success unless you config NAT in one way which make the source/destination of packet NATing to new IP and hence the ping reply is drop.

[Richard Burts · Accepted solution]

There are several things in this post that are not clear. It suggests that NAT is configured on the core switch. What kind of switch is this core switch? There are very few switches that support NAT. I am also puzzled by references to interface s2/1. What kind of interface is this?

I am also not clear about the diagram which does show 2 lines from the remote office (one to ISP router and one to core switch). Are these really 2 separate paths from the remote office? Or is it just suggesting communication from the remote office to both devices with the path from remote office to the core switch going through the ISP router?

Despite not knowing these things I do have a guess at what the problem is. The diagram shows a dynamic NAT set up to translate inside address going to outside. And the dynamic NAT would allow responses from outside to the inside device. But the dynamic NAT does not allow traffic originated from the outside device to an inside device. So when the remote office attempts to ping the core switch it is outside to inside and the NAT does not work for that.

[Richard Burts]

I am glad that our suggestions have been helpful. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. This community is an excellent place to ask questions and to learn about networking. I hope to see you continue to be active in the community.

[MHM Cisco World]

I really dont get the issue here?
are there two links or one link in remote Site?

[deypuchka]

Only one and the dotted lines indicates the connections that I want to ping.

[Richard Burts]

Thank you for clarifying that the dotted lines indicate where you want to communicate and do not indicate separate paths from the remote office.