Dynamic NAT help

[mchockalingam]

Hi All,

I am trying to configure a dynamic NAT for a subnet. The subnet I have is 10.32.28.0/21 and I would like to xlate it to x.x.98.0/23.

Do I need to use policy NAT for this?

thanks

[Fernando_Meza]

Hi .. You should be able to configure it as below

nat (inside) 1 10.32.28.0 255.255.248.0

global (outside) 1 x.x.98.0 netmask 255.255.254.0

Be aware that /21 mask on your case applies to network 10.32.24.0 ( range 10.32.24.1- 10.32.31.254)

I hope it helps .. please rate it if it does !!!

[mchockalingam]

I tried entering

FWSM1(config)# nat (inside) 1 10.32.28.0 255.255.248.0

and I get this message.

WARNING: IP address <10.32.28.0> and netmask <255.255.248.0> inconsistent

So, I entered it as a

FWSM1(config)# nat (inside) 1 10.32.28.0 255.255.252.0

FWSM1(config)# nat (inside) 1 10.32.32.0 255.255.252.0

and I did not get any warning. NAT seems to be working though.

[Fernando_Meza]

Hi .. yes that is because the 10.32.28.0 /21 falls in to the network address 10.32.24.0 / 21.

[mchockalingam]

Oops! that is correct. I do not know what I was thinking. Having two /22 works better.

Thank you so much!