Dynamic service registration allows a database to automatically register its services with a listener

without manual configuration in LISTENER.ORA. Let’s analyze each option:

A . The definition for LISTENER_1 requires a CONNECT_DATA section to enable dynamic service

registration.

False. The CONNECT_DATA section is part of a client-side TNSNAMES.ORA entry for connecting to a

service, not for listener registration. Dynamic registration is handled by the database’s LREG (Listener

Registration) process, which uses the LOCAL_LISTENER parameter to locate the listener’s address

(e.g., host1.abc.com:1521). No CONNECT_DATA is needed in the listener address definition itself. This

option confuses client connection syntax with listener configuration.

Mechanics:The listener address in TNSNAMES.ORA (LISTENER_1) is sufficient for LREG to find and

register with it, as long as the listener is running at that address.

B . LISTENER_1 must also be defined in the LISTENER.ORA file to enable dynamic service registration.

False. Dynamic registration doesn’t require the listener to be explicitly defined in LISTENER.ORA. The

LOCAL_LISTENER parameter pointing to LISTENER_1 (resolved via TNSNAMES.ORA) tells LREG where

to register services. If the listener is running on host1.abc.com:1521, LREG will find it without a

LISTENER.ORA entry. However, LISTENER.ORA is needed tostartthe listener process, but that’s

separate from dynamic registration.

Practical Note:If LISTENER.ORA isn’t configured, a default listener might run on port 1521, but the

question implies LISTENER_1 is operational.

C . The LREG process registers services dynamically with the LISTENER_1 listener.

True. In Oracle 23ai, the LREG background process (replacing PMON’s registration role in earlier

versions) dynamically registers database services with listeners specified by LOCAL_LISTENER. Here,

LOCAL_LISTENER=LISTENER_1 resolves to host1.abc.com:1521 via TNSNAMES.ORA. LREG

periodically sends service information (e.g., service names, instance details) to the listener, enabling

clients to connect without static configuration.

Mechanics:LREG uses the TNS alias (LISTENER_1) to locate the listener’s IP and port, registers

services like orcl or orclpdb, and updates the listener’s service table. This happens automatically

every 60 seconds or on significant events (e.g., instance startup).

D . Dynamic service registration cannot be used for this database instance.

False. The setup (LOCAL_LISTENER set and a valid TNSNAMES.ORA entry) explicitly supports dynamic

registration. No blockers (e.g., REGISTRATION_EXCLUDED_LISTENERS) are mentioned, so LREG can

function normally.

E . There are two listeners named LISTENER and LISTENER_1 running simultaneously using port 1521

on the same host as the database in LISTENERS.

False. The question mentions only LISTENER_1 in the SPFILE and TNSNAMES.ORA. There’s no

evidence of a second listener (LISTENER) or a LISTENERS configuration (possibly a typo). Two listeners

can’t share the same port (1521) on the same host due to port conflicts unless explicitly configured

with different IPs, which isn’t indicated here.

Reference:Oracle Database Net Services Administrator’s Guide 23ai, "Understanding Dynamic Service

Registration"; Oracle Database Reference 23ai, "LOCAL_LISTENER Parameter."