Add info about is_distributed_network_name column

Author: PiJoCoder

docs/relational-databases/system-catalog-views/sys-availability-group-listeners-transact-sql.md

@@ -37,7 +37,8 @@ ms.assetid: b5e7d1fb-3ffb-4767-8135-604c575016b1
 |**port**|**int**|The TCP port number configured for the availability group listener.<br /><br /> NULL = Listener was configured outside [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] and its port number has not been added to the availability group. To add the port, pleaseuse the MODIFY LISTENER  option of the [ALTER AVAILABILITY GROUP](../../t-sql/statements/alter-availability-group-transact-sql.md)[!INCLUDE[tsql](../../includes/tsql-md.md)] statement.|  
 |**is_conformant**|**bit**|Whether this IP configuration is conformant, one of:<br /><br /> 1 = Listener is conformant. Only "OR" relations exist among its Internet Protocol (IP) addresses. *Conformant* encompasses every an IP configuration that was created by the [CREATE AVAILABILITY GROUP](../../t-sql/statements/create-availability-group-transact-sql.md)[!INCLUDE[tsql](../../includes/tsql-md.md)] statement. In addition, if an IP configuration that was created outside of [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)], for example by using the WSFC Failover Cluster Manager, but can be modified by the ALTER AVAILABILITY GROUP tsql statement, the IP configuration qualifies as conformant.<br /><br /> 0 = Listener is nonconformant. Typically, this indicates  an IP address that could not be configured by using [!INCLUDE[ssNoVersion](../../includes/ssnoversion-md.md)] commands and, instead, was defined directly in the WSFC cluster.|  
 |**ip_configuration_string_from_cluster**|**nvarchar(max)**|Cluster IP configuration strings, if any, for this listener. NULL = Listener has no virtual IP addresses. For example:<br /><br /> IPv4 address:  `65.55.39.10`.<br /><br /> IPv6 address:  `2001::4898:23:1002:20f:1fff:feff:b3a3`|  
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+|**is_distributed_network_name**|**bit**|**Applies to**: [!INCLUDE[sql-server-2019](../../includes/sssql19-md.md)] CU8<br /><br /> This column indicates the listener is a distributed network name (DNN) listener if value set to 1. For more information see [Configure a DNN listener for an availability group](/azure/azure-sql/virtual-machines/windows/availability-group-distributed-network-name-dnn-listener-configure) |
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