JAMES-3955 WARNING logs upon closing channels
diff --git a/backends-common/rabbitmq/src/main/java/org/apache/james/backends/rabbitmq/ReactorRabbitMQChannelPool.java b/backends-common/rabbitmq/src/main/java/org/apache/james/backends/rabbitmq/ReactorRabbitMQChannelPool.java
index a98d11f..10b2d5e 100644
--- a/backends-common/rabbitmq/src/main/java/org/apache/james/backends/rabbitmq/ReactorRabbitMQChannelPool.java
+++ b/backends-common/rabbitmq/src/main/java/org/apache/james/backends/rabbitmq/ReactorRabbitMQChannelPool.java
@@ -111,6 +111,10 @@
 
         @Override
         public void close(int closeCode, String closeMessage) throws IOException, TimeoutException {
+            // https://www.rabbitmq.com/amqp-0-9-1-reference.html#domain.reply-code
+            if (closeCode >= 300) {
+                LOGGER.warn("Closing channel {} code:{} message:'{}'", getChannelNumber(), closeCode, closeMessage);
+            }
             delegate.close(closeCode, closeMessage);
         }
 
@@ -121,6 +125,10 @@
 
         @Override
         public void abort(int closeCode, String closeMessage) throws IOException {
+            // https://www.rabbitmq.com/amqp-0-9-1-reference.html#domain.reply-code
+            if (closeCode >= 300) {
+                LOGGER.warn("Closing channel {} code:{} message:'{}'", getChannelNumber(), closeCode, closeMessage);
+            }
             delegate.abort(closeCode, closeMessage);
         }