On 01/29/2016 05:34 AM, Pat Scharmer wrote:
So the duplicate DNS responses has returned. Any thoughts on what would cause duplicate DNS responses? I'm running unbound with DNSSEC activated and it is using the root name servers as the upstream resolvers.
Wild guess, but I'd suspect a routing issue. You'd get duplicate responses if the requests are being sent twice. Have you recently made any changes to iptables or your kernel routing table? Do you get double responses if you ping another server, say example.com?
I mention this guess because last year I was messing with packet forwarding on a personal machine and had duplicated packets (which manifested itself as log warnings, double ping replies, and slow performance) until I fixed my iptables rules.