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New Member

link two networks with same ip network FWSM


I have to link 2 networks with the same IP network.

each IP network is on a séparate FWSM

could you help me for the configuration

nat , global , static

Everyone's tags (1)
Cisco Employee

Re: link two networks with same ip network FWSM


For starters, here is a document giving all information regarding configuring NAT with FWSM version 3.2:

The 2 IP networks that you are referring, do you need complete 2-way communication between them or is it just going to be 1-way communication? if it is going to be 2-way communication, you will meed to statically translate both the networks to different subnets. That is assuming the follwing:

IP network: A/24


static (in,out) B A netmask


static (in,out) C A netmask

Now the IP network A in FWSM1 when trying to access the network behind FWSM2, they will actually need to specify the destination P in the subnet C (because of the static NAT) and also the source IP will get translated to an IP in the subnet B.

When the network behind FWSM2 tries to do the same, the destination will be specified in subnet B and the source IP will get translated to the subnet C.

We need to ensure all the corresponding ACLs and routing reflect these 2 IP subents, B and C.

Again, I am assuming that this is your network requirement and i hope i am correct Do send your detailed requirement if this is not the case and we can recommedations based on that.

All the best!!

Thanks and Regards,


New Member

Re: link two networks with same ip network FWSM

thank you Prapanch for your answer , I will test it a soon as

possible depend on the FWSM


I will inform you if I need more information.

Best regards

jean louis