DNS Forwarder "Validation error, please try again later"

[edublogger]

Hi,

 

Can anyone point me in the right direction with this?

 

We're using new DNS filtering system which needs me to add new DNS forwarders on our internal DNS servers. If I add in Google (8.8.8.8) or our ISP's DNS addresses they resolve and validate instantly, but if I add in the filtering system I get a "Validation error, please try again later" error and external DNS resolution stops working.

 

I've spoken to our ISP who say they have allowed us access to the new DNS IPs but it's still not working. The filtering company and ISP are just passing the buck between each other. Does anyone know what is likely causing this error so I can go back to them with something solid?

 

Thanks

[tmcd35]

What DNS servers is the filtering system point to? Smells like the filtering systems isn't forwarding requests to either your ISP's DNS or Google's DNS.

[edublogger]

It's a cloud based filtering system. So it's an IP on the Internet beyond our ISP.