release-request-fe3c4418-17ca-4f25-abb0-4ebd39ddf162-for-git_pi-release-4315938 snap-temp-L58200000099370312

Change-Id: I2e69b2328beeef00aa94f21438c01a694d1686dd
diff --git a/config.c b/config.c
index b147868..2d7085b 100644
--- a/config.c
+++ b/config.c
@@ -180,8 +180,11 @@
     logmsg(ANDROID_LOG_WARN, "dns64_detection -- error, sleeping for %d seconds", backoff_sleep);
     sleep(backoff_sleep);
     backoff_sleep *= 2;
-    if(backoff_sleep >= 120) {
-      backoff_sleep = 120;
+    if(backoff_sleep >= 1800) {
+      // Scale down to one DNS query per half hour. Unnecessary DNS queries waste power, and the
+      // benefit is minimal (basically, only limited to the case where a network goes from IPv6-only
+      // to IPv6 with NAT64).
+      backoff_sleep = 1800;
     }
   }
 }