This project contains python code that issues DNS queries to resolvers and compares the resulting DNS responses.
The comparison can either note the number of equal and unequal resource records in the answer, or can compare the results side by side, showing the differences like diff.
dnspython is a prerequisite. You must have the very latest dnspython installed. Note that dnspython version 1.11.0 has multiple releases and only the latest fixes a bug that ResolverCompare expresses. In dns/resolver.py, line 881 should be:
if rcode != dns.rcode.SERVFAIL or not self.retry_servfail:
The bug is that this line is missing "self." in earlier releases.