diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index fd17be6fb2c..ddfe8993d2c 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -393,6 +393,9 @@ Release 2.8.0 - UNRELEASED
     HADOOP-12752. Improve diagnostics/use of envvar/sysprop credential
     propagation (Steve Loughran via cnauroth)
 
+    HADOOP-12788. OpensslAesCtrCryptoCodec should log which random number generator is used.
+    (Wei-Chiu Chuang via umamahesh)
+
   OPTIMIZATIONS
 
     HADOOP-11785. Reduce the number of listStatus operation in distcp
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/OpensslAesCtrCryptoCodec.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/OpensslAesCtrCryptoCodec.java
index 4ca79b307d6..63c382c16e0 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/OpensslAesCtrCryptoCodec.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/crypto/OpensslAesCtrCryptoCodec.java
@@ -61,6 +61,9 @@ public class OpensslAesCtrCryptoCodec extends AesCtrCryptoCodec {
         Random.class);
     try {
       random = ReflectionUtils.newInstance(klass, conf);
+      if (LOG.isDebugEnabled()) {
+        LOG.debug("Using " + klass.getName() + " as random number generator.");
+      }
     } catch (Exception e) {
       LOG.info("Unable to use " + klass.getName() + ".  Falling back to " +
           "Java SecureRandom.", e);