Bug #26730000 SERVER_ID LOOKS SET TO VALID VALUE STILL START SLAVE FAILS WITH ER_BAD_SLAVE

Now, default server_id is set to 1 and user gets a warning
if it is not set during server initialization. But, there
is no WARNING and starting slave fails when server-id is
not supplied by users during server starts.

To fix the problem, remove the check on server_id_supplied
on starting slave, and report a warning if the server-id
is not supplied by users during server starts.

Author: Daogang Qu

sql/mysqld.cc

@@ -5627,7 +5627,7 @@ int mysqld_main(int argc, char **argv)
     unireg_abort(MYSQLD_ABORT_EXIT);
   }
 
-  if (((opt_initialize || opt_initialize_insecure) && !server_id_supplied))
+  if (!server_id_supplied)
     LogErr(WARNING_LEVEL, ER_WARN_NO_SERVERID_SPECIFIED);
 
 

sql/rpl_slave.cc

@@ -9477,7 +9477,7 @@ bool start_slave(THD* thd,
       is_error= true;
       my_error(ER_MASTER_INFO, MYF(0));
     }
-    else if (server_id_supplied && (*mi->host || !(thread_mask & SLAVE_IO)))
+    else if (*mi->host || !(thread_mask & SLAVE_IO))
     {
       /*
         If we will start IO thread we need to take care of possible