I have an alternative DNS server configured. I had expected the alternative to route traffic only when the primary is down. Instead, traffic seems to be roughly evenly spread across both the DNS server and alternative DNS server.
It seems odd that this would not be a failover, or that there would be no way to control where the traffic gets redirected. Ideally I’d like for the Alternative DNS server to act as a failover, but it seems it’s not what it’s designed for.
I guess I was just confused by the usage of the word ‘alternative’, it seemed to imply it would be used ‘instead of’ instead of as a second, equally balanced traffic. I guess that might just be me, and I couldn’t see any hovertext explaining it’s behaviour in the UI, so I was interested.
As to why I was looking for a failover in the first place, It’s not really a need. I have two DNS servers installed on Raspberry PIs, and I was just expecting to see traffic on one unless the other went down. I just presumed that if I unplugged or powered one down, requests for DNS would slow down as they repeatedly fail. I’ve not tested that, it’s just an assumption. If I card that much about it I guess I would put my own load balancer in between.
I think that would help, personally I would be less inclined to think of it as a failover then. Some hovertext or a note explaining the behavior would be useful too, if possible. That’s pretty much what I looked for before posting on the forums.
I agree with @HDCerberus and kudos for doing all that work to figure out what was going on.
I’m not convinced that all routers and Operating Systems are clear on what they do with DNS fields. I’ve selected my own DNS settings in Windows and pcWRT. Using ‘nslookup google.com’ from the Windows Powershell CLI shows me that Windows is consistently picking the first DNS entry. Here’s an example where the result shows CloudFlare’s server and DNS address.
Regardless, the advantage of an agile company like bigXi LLC is that they can be clear on their implementation with a single line of text near the DNS setting, that indicates their approach is to use load-balancing. I’ve also noticed that they sometimes use an information icon next to some fields which could be used instead of a line of text.
It would also be helpful to have a note when setting the DNS in pcWRT that the DNS settings in the ‘Settings>Internet’ page will be ignored if ‘Access Control’ is enabled. (I believe that is the case, but others can confirm.)