Some people just have a DNS cache problem…
Security or performance critical
You may have an existing recursive resolver which doesn’t give you what you need, or be planning a new one and know you need something with the highest specification.
- Reliable, secure recursive DNS resolution is important in any DNS service. But for you, any problem disrupting the service would be a business disaster. You need an ultra-secure, highly reliable solution.
- You resolve a high volume of DNS queries. You need a high-performance solution.
It may be too difficult trying to build and maintain your own solution on a general purpose server to meet these goals. A suitable appliance will make it much easier.
Off-site DNS cache
If you are relying on off-site DNS caching services – either your own server on another network or an outsourced service – latency is often a problem. In addition:
- You are relying on your internet connection for resolution of DNS queries, so service performance or even availability cannot be guaranteed.
- Free DNS services like those from OpenDNS or Google’s “Public DNS” normally limit the maximum number of connections allowed from a specific IP address. If you are using NAT (Network Address Translation) for a large number of users this limit can cause DNS to timeout, resulting in some requests to fail.
So you need to put a local recursive resolver in your own network. But you don’t need headaches: you need it easy, secure and reliable.