Destination NAT with different subnet of Outside interface.

[ParvezAhmad]

Hello,

Outside interface of Palo Alto firewall is configured with aaa.bbb.ccc.ddd /30 subnet.

I have some servers in DMZ those need to be accessed via internet with IP address(es)/subnet ZZZ.XXX.YYY.VVV/24.

I have configured Destination Nat( including Security Policy) for these servers with the IP addresses as mentioned above.

Please let me know how this can work? Do we need to add static route on upstream router for new subnet?

Regards,

[panos]

so you mean zzz.xxx.yyy.vvv/24 is public ip subnet also ?

[ParvezAhmad]

Yes, zzz.xxx.yyy.vvv/24 is public subnet.

[panos]

ok so when accessing this /24 subnet from internet that traffic should come to aaa.bbb.ccc.ddd /30's interface(upstream should route that traffic)

you can add this /24 subnet to the outside interface as second.

[ParvezAhmad]

panos, would please let me know how we can add secondary IP address to Outside interface of FW?

[panos]

[ParvezAhmad]

panos, Thanks a lot.

[ParvezAhmad]

panos, I have configured upstream router with static routes for secondary subnet towards outside interface of PA FW.

Apart from this Destination Nat is configured with Security Policies to allow the traffic.

Would you please let us know how to troubleshoot? still the servers are not accessible from internet form secondary subnet.

Regards,

Parvez  

[panos]

you may use packet capture to troubleshoot while accessing from outside to that secondary subnet

so that we'll see if traffic comes(and we drop)  or not

if not so problem is related to upstream

[Gregoux]

be careful about the rule

you have to create the rule from internet to DMZ base on the ZZZ.XXX.YYY.VVV/24 ip and not on the NAT ip.

if you have a rule like deny all at the bottom of the rule list, you will see if a deny action is present in the traffic log.

regard's

[VinceM]

Keep that in mind :

Hope help

V.

[ParvezAhmad]

Gregoux, If I will put deny all at the bottom, Do we need to allow separate rules outside to outside, DMZ to DMZ and Inside to inside for all traffic.

[ParvezAhmad]

Thanks a lot. I created the rules as mentioned in this snapshot.

[ParvezAhmad]

Thanks a lot . The migration was successful.