have two router with two different ISP links. They have both different global IP addresses.
Both connected with Layer 3 switch in different VLANs. my lan 172.28.92.x subnet translated by pix into x.x.x.38 and pix send it to layer 3 switch.
I have applied the Policy base routing on Layer 3 switch. Now when switch get the IP of x.x.x.38 subnet it send to ISP B router.
rest all traffic goes to ISP A.
But now problem is that this happens when traffic from subnet x.x.x.38 goes outside. It is still coming via ISP A router. Bcz x.x.x.38 subnet belongs
to ISP A global address pool.
Then I apply the nat on ISP B router and when B router gets traffic from source x.x.x.38, it nat it into x.219.212.211 which is the global IP address
assigned by the ISP B.
I can see the nat translation that x.x.x.38 is translating into x.x.219.212.211. and getting back from Internet and coverting back to x.x.x.38.
But when i applied a Access-list on ISP A router outside interface
access-list 101 deny ip any host x.x.x.38
access-list 101 permit ip any any
I all internet browsing stop working. Means still it is using the returing path via ISP A. Though I nat x.x.x.38 source into ISP B IP address x.219.212.211.
Why it is happening. Over the internet x.219.212.211 belong to ISP B. It should comes into my network via ISP B not ISP A.
Can anyone help me to sort out this problem. I will b very greatful to you.
I have also atatached the network diagram for your kind review.
Is there anyway to check which return path my outgoing traffic use on its arrival.