sp_validate_replica_hosts_as_publishers (Transact-SQL MetaData) Definition

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The meta data is from an SQL 2012 Server.

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Definition:

sys.sp_validate_replica_hosts_as_publishers(nvarchar @original_publisher
, nvarchar @publisher_db)

MetaData:

 --   
--  Name: sp_validate_replica_hosts_as_publishers  
--   
--  Descriptions: Retrieve the redirected publisher for the specified   
--                publisher database pair. If the publisher is not  
--                currently redirected, return NULL.   
--   
--                For redirected publishers, a connection is made to the  
--                redirected publisher to determine whether the target of  
--                redirection is an availability group VNN Name. If it is  
--                not, a message is returned indicating that the redirected  
--                publisher is not associated with an availability group.  
--   
--                  The availability group primary is then queried for the  
--                  names of the hosts of the member replicas. Each host in   
--                  turn is validated as a publisher for the database.  
--   
--                In general, the stored procedure will attempt to continue  
--                  after encountering errors, and will try to validate all  
--                  of the known replica hosts associated with the availability  
--                  group.  
--   
--  Parameters: as defined in create statement  
--   
--  Returns: 0 on success, 1 on failure; on failure errors are raised  
--   
--  Security: Public procedure invoked via RPC. check caller for db_owner   
--            or in the PAL of a publication of the named pubisher check  
--   
create procedure sys.sp_validate_replica_hosts_as_publishers  
(  
    @original_publisher sysname,  
    @publisher_db sysname,  
    @redirected_publisher sysname output  
)  
as  
begin  
  
   set nocount on  
  
   declare   
        @target_server sysname,  
        @publisher_linked_server sysname,  
        @dbname sysname,  
        @retcode int,  
        @use_caller_credentials bit  
          
   set @redirected_publisher = null  
   set @target_server = null  
   set @publisher_linked_server = null  
   set @dbname = db_name()  
   set @use_caller_credentials = 1  
     
    --  Has to be executed from a distribution database  
    --   
    if (sys.fn_MSrepl_isdistdb (@dbname) <> 1)  
    begin  
        raiserror(21874, 16, -1, 'sys.sp_validate_replica_hosts_as_publishers', @dbname)  
        return 1  
    end      
          
    --  Verify input parameters are not NULL  
    --   
    if @original_publisher is null or  
        @publisher_db is null  
    begin  
        raiserror (21875, 16, -1, 'sys.sp_validate_replica_hosts_as_publishers')  
        return 1  
    end  
      
    --  Security check  
    --   
    if is_member(N'db_owner') <> 1  
    begin  
        exec @retcode = sys.sp_MSrepl_DistDBPALAccess @original_publisher  
          
        if (@retcode <> 0) or (@@error <> 0)  
        begin  
            raiserror (21873, 16, -1, 'sys.sp_validate_replica_hosts_as_publishers')  
            return 1  
        end  
    end  
          
    --  If the publisher of the database has not been redirected  
    --  return without performing any validation.  
    --   
    select @redirected_publisher = redirected_publisher  
    from MSredirected_publishers  
    where upper(original_publisher) = upper(rtrim(@original_publisher))  
    and publisher_db = rtrim(@publisher_db)  
          
    if @redirected_publisher is null  
    begin  
        raiserror(21871, 10, 0, @original_publisher, @publisher_db);  
        return 0  
    end  
          
    --  Verify that the original publisher is a SQL Server publisher of this   
    --  distributor.  
    --   
    if not exists (  
        select name from msdb.dbo.MSdistpublishers  
        where upper(rtrim(@original_publisher)) = upper(name) collate database_default  
        and N'MSSQLSERVER' = upper(publisher_type))   
    begin  
        raiserror (21876, 16, -1, @@servername, @original_publisher, @publisher_db)  
        return 1  
    end  
      
    --  Verify that there is a sysservers entry for the original publisher   
    --  at the distributor.  
    --   
    if not exists (  
        select srvid  
        from master..sysservers  
        where upper(srvname) collate database_default = upper(rtrim(@original_publisher)))  
    begin  
        raiserror (21877, 16, -1, @original_publisher, @publisher_db)  
        return 1  
    end  
                  
    --  Create a linked server to connect to the target of redirection.  
    --   
    exec @retcode = sys.sp_hadr_create_linked_server @original_publisher, @publisher_db,  
        @redirected_publisher, @publisher_linked_server output, @use_caller_credentials  
    if @retcode <> 0  
    begin  
        return 1  
    end  
      
    --  Query the availability group primary for the names of the member replicas associated  
    --  with the publisher database and validate the host server for each replica as a  
    --  replication publisher.   
    --   
    exec @retcode = sys.sp_hadr_validate_replica_hosts_as_publishers @original_publisher,   
        @redirected_publisher, @publisher_db, @publisher_linked_server   
      
    return @retcode  
end