hi every body.
I have been wrecking my small brain to make it work.
Some Context:
If a interface is configured with " ip nat inside" then order of operation is first look up destionation ip, then perform nat,
If a interface is configured with " ip nat outside" then order of operation is first nat then routing table look up.
Based on cisco web side that is what i learned
If i configure :
ip nat inside destination list 1 pool zee
then any packet entering " inside nat interface " whose destination matches the ip referenced in access list 1,will have destination ip replaced by an ip from pool zee after router performs the routing look up.
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Armed with this new info, i tried to came up with scenario to load balance the traffic.
here is my set up:
hosts--------------f0 (NAT) f1-----------------servers
Hosts know the servers by ip 199.199.199.1
My goal is every time router receives the packet destined for 199.199.199.1, it will change the ip address to 200.200.200.1, 200.200.200.2 in round robin fashion,( two servers with ip address 200.200.200.1,200.200.200.2)
At my NAT router, i made these configurations
Int f0
ip nat inside
Int f1
ip nat outside
access-list 1 permit 199.199.199.1
ip nat pool zee 200.200.200.1 200.200.200.2 netmask 255.255.255.0 type rotary
ip nat inside destination list 1 pool zee
loopback1
199.199.199.1/24
Let say a host sends a packet to 199.199.199.1
here is my understanding
packets enters the " ip nat inside interface ". router performs the routing table look up and finds the match ( as we configured the loopback 1)
next router performs NAT and picks 200.200.200.1 from pool and replaces the destination ip by it.
Next router performs look up and forwards it to one of the server with ip address 200.200.200.1
But when i performed the lab, and issue ping from host to 199.199.199.1, nat will not perform nat and simply sends the echo back to host( I used debug ip nat, debug ip packets on router to verify but it will not translate)
any suggestion?
you guys have a great weekend.
