I'm not quite sure how exactly to phrase what it is I need, which makes searching challenging. :) Basically I've got Bind DNS running on RackSpace instances and I want to set named up so that any of my clients can recursively query without risking an open resolver.
All clients are Linux based, though the Android mobile clients are a bit harder to configure. I know that I can setup caching instances of Bind on the laptops and gateways, which might allow some form of key based authentication of recursive requests. I am unsure if this is possible on Android clients, though.
Note that I know that I can use a wide array of public resolvers, like those provided by Google, but for reasons not relevant here, I need to run my client requests through my own server if at all possible. I have tried wading through the man pages and online docs, but I'm not clear on exactly what I need to look for.
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Clients are not connected through a VPN, and I'm trying hard to avoid that for certain reasons. Just one of those reasons is that the extra memory footprint and CPU load of even lightweight, low security VPNs is challenging on the most affordable cloud instances. A second is that VPNs add a layer of complexity in almost all Android implementations that I've seen that is super annoying if not truly needed for security.
I am not "married" to Bind as a name server. If there are other FOSS name servers that might be more useful in this particular instance, I'll happily give them a spin. I've simply spend 15+ years using Bind and stopped thinking about alternatives.
I am also not greatly concerned about anyone trying to hack the DNS responses to my clients. If we were living in a world like that the DNS system was designed for, I'd happily run an open resolver. Alas, miscreants of various stripes tend to abuse my open resolver to attack third parties.
I am not running a "mission critical" network here. It is used by few people, for nothing financially or personally critical, rather for experimentation, development and testing.