support RabbitMQ cluster configuration.

src/DotNetCore.CAP.RabbitMQ/CAP.RabbiMQOptions.cs

@@ -37,7 +37,10 @@ namespace DotNetCore.CAP
         /// <summary> The topic exchange type. </summary>
         public const string ExchangeType = "topic";
 
-        /// <summary>The host to connect to.</summary>
+        /// <summary>
+        /// The host to connect to.
+        /// If you want connect to the cluster, you can assign like “192.168.1.111,192.168.1.112”
+        /// </summary>
         public string HostName { get; set; } = "localhost";
 
         /// <summary>

src/DotNetCore.CAP.RabbitMQ/IConnectionChannelPool.Default.cs

@@ -76,7 +76,6 @@ namespace DotNetCore.CAP.RabbitMQ
         {
             var factory = new ConnectionFactory
             {
-                HostName = options.HostName,
                 UserName = options.UserName,
                 Port = options.Port,
                 Password = options.Password,
@@ -86,6 +85,13 @@ namespace DotNetCore.CAP.RabbitMQ
                 SocketWriteTimeout = options.SocketWriteTimeout
             };
 
+            if (options.HostName.Contains(","))
+            {
+                return () => factory.CreateConnection(
+                    options.HostName.Split(new[] { "," }, StringSplitOptions.RemoveEmptyEntries));
+            }
+
+            factory.HostName = options.HostName;
             return () => factory.CreateConnection();
         }