DATE :-- 1st Sep 2014

ORA-12528: TNS:listener: all appropriate instances are blocking new connections

Error :--

SQL> conn sys@DBSTP11G as sysdba

Enter password:

ERROR:

ORA-12528: TNS:listener: all appropriate instances are blocking new connections

Warning: You are no longer connected to ORACLE.

SQL> exit

         

Resolution :--

DBSTP11G =

  (DESCRIPTION =

   (ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.163)(PORT=1521))

   (CONNECT_DATA =

    (SERVER=DEDICATED)

    (SID_NAME=DBSTP11G)

    (SERVICE_NAME=DBSTP11G)

    (UR=A)

   )

  )

UR=A 

It will resolve the issue 

 network issue resolved