ORA-12514 error on Data Guard setup.

The special service db unique name DGMGRL may not have been correctly registered with the listener, resulting in this starting problem.

Create a listener service and register it with the local listener on both the primary and failover/standby database instances if you want DGMGRL to automatically restart a standby database instance.

GLOBAL DBNAME should be a concatenation of the db name and the domain name: db unique name DGMGRL.db domain,

For example:

LISTENER = (DESCRIPTION =
(ADDRESS_LIST=(
      ADDRESS=(PROTOCOL=tcp)(HOST=host_name) (PORT=port_num)
)))

SID_LIST_LISTENER=
   (SID_LIST=(
   SID_DESC=(SID_NAME=sid_name)
  (GLOBAL_DBNAME=db_unique_name_DGMGRL.db_domain)
   ORACLE_HOME=oracle_home)))

To know furthermore about Listener.ora & tnsnames.ora, visit the below-mentioned link:

www.support.dbagenesis.com

Oracle networking is very important when you want to connect a particular database. To setup network, we must have listener running on the server and tnsnames.ora configured on the client side. Configure listener.ora Configure listener.ora in Multi-Tenant Configure tnsnames.ora Make sure you open the listener port before configuration iptables -I INPUT -p tcp --dport 1521 -j ACCEPT Configure listener.ora The listerner.ora file contains server side network configuration parameters. It can be foun