With Google Public DNS 8.8.8.8 the ratio of DNS requests to DNS response is high

[Masajjage robert kasoma]

Connectivity Tests: Very fine (no packet Loss)

Check the attached ping test results.

UGW DNS traffic KPI is abnormal, the number of DNS response is so less compared to the number requests ... check below graphical presentations.

Network Design:

At the firewall, there is a NAT of Many Private IPs to a few Public IP.

We would like to know what is causing this less response to our many requests sent to Google DNS.

regards

Robert K M

[Alex Dupuy]

Google Public DNS imposes certain rate, bandwidth, amplification, and other limits on queries from clients. If you are configuring clients (via DHCP or other means) to send queries to Google Public DNS directly at 8.8.8.8 and its other addresses (especially if you are using CG-NAT to map many clients onto a few public IP addresses), these rate limits are very likely responsible for the low rate of responses.

As noted in our FAQ, we request that large users like ISPs coordinate with us before sending high volumes of traffic by opening a rate limit increase request on our issue tracker.

If you send high levels of traffic to our service either currently, or potentially in the future, please open a rate limit increase request, providing as much of the requested information as possible, and we can usually increase these limits within two business days.

Please remember that Google Public DNS is a service without an SLA, and we cannot commit to any level of service; while we strive to provide the service to as many people as want to use it, we cannot guarantee that all queries will receive a response.

[Masajjage robert kasoma]

Thank you so much Alex for the prompt response on my post, kindly help and throw more light on the limitations, do you implement DoS in your security solutions? if yes what are the limitations imposed (like how many requests do you expect from one public IP) for us to redesign our NAT solution.