Meraki behind PA850 - Site-to-site, Error Unfriendly NAT configuration

[mwiadrowski]

Hi All, 

I am working on a implementation of the Meraki MXs behind PA850 - Site-to-site ( hub and spoke). I am getting error on the VPN status: NAT type: Unfriendly. This security appliance is behind a VPN-unfriendly NAT, which can be caused by upstream load balancers or strict firewall rules.

It seems to be working only when i use static one to one NAT rules. NAT type: Friendly. This security appliance is behind a VPN-friendly NAT, locally using....

It is not feasible to use static ip for every MX. 

I am hoping that someone ran into similar issue and was able to figure out the working configuration. 

Thanks!

Marcin

[BPry]

@mwiadrowski,

That's a Meraki thing and is automatic if memory serves correctly. The Meraki does a simple check to see if the source port is being modified between connections. You'll need to ensure that the NAT policy that the Meraki is using on the PA-850 maintains the same source port when it leaves the PA-850 to get this to form up properly.

[mwiadrowski]

@BPry 

Thank you for your reply. 

Would you provide some guidance/ KBa, how to achieve your suggested solution?

Thank you 

Marcin

[BPry]

@mwiadrowski,

So I imagine that the Meraki device simply hits a DIPP NAT rule (Dynamic IP and Port). You'll need to make another NAT policy specifically for the Meraki device that specifies the Translation Type as 'Dynamic IP' instead of 'Dynamic IP and Port'. This would allow a friendly NAT as far as the Meraki is concerned. 

[jvallejo · Accepted solution]

In case someone comes across this as well.