DNS problem

[cetta]

Hi all,

My local network is using Local DNS server and Local DNS servers using external DNS forwarder for DNS queries. External DNS servers are my ISP's DNS servers. But in Smartdefense i view blocked DNS connection. This logs are creating every 2 seconds. Log details;

Attack Name:Invalid DNS
Attack Information: Out of state DNS reply
Source: sometimes External Interface, sometimes My ISP's DNS server , sometimes Internal Mail server (in DMZ)
Destination: sometimes My internal DNS servers, sometimes My ISP's DNS server IP address etc.

Accept Domain name over UDP is enabled.

I think this connections is not a attack but blocked by Smartdefense. What is a problem?

[kva.kva]

You can try to disable "UDP protocol enforcement" in SmartDefence settings. Or try to "play" with another SmartDefence settings for DNS.

[cetta]

Thanks for reply,

If i will do it, that connections are will not blocked by gateway but Checkpoint says Severity:Critical for this condition. I think this is not safe.

I want to learn, what cause this problem?