Add instructions for disabling pdns caching

README.md

@@ -239,6 +239,12 @@ PowerDNS Configuration
     # send queries for the load balancing domain to the pipe backend
     pipe-regex=best\.stanford\.edu$
 
+    # disable pdns caching, so it queries lbbe for every query it receives
+    cache-ttl=0
+    domain-metadata-cache-ttl=0
+    max-cache-entries=0
+    negquery-cache-ttl=0
+    query-cache-ttl=0
 
 Starting the poller and PowerDNS
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