Earlier quoted context omitted.
Considering this is DNS there has been a historical limit of 512 bytes. Despite this not usually being a limitation now you are really pushing the ideal packet size with hundreds of answers each of which are multiple bytes. High chance of packets being dropped.
> Considering this is DNS there has been a historical limit of 512 bytes. Only with UDP transport, longer responses are told to requery via TCP.
Re: Amazon Route 53 Releases Auto Naming API for Service Name Management/Discovery
#21These days EDNS0 allows bigger UDP responses in many cases, which may mean some fragment re-assembly. Unfortunately there are a staggering number of networks and firewalls that don't open TCP 53, and also ones that don't permit UDP fragments. So if you want DNS to work reliably /everywhere/, sadly it's wise to stay below the 512 limit.