ORA-12541: TNS: No Listener — The One That Wastes Your Morning

Nov 3, 2025 · 1 min read · You start your day, coffee in hand, and Oracle throws this: ORA-12541: TNS: no listener Classic. Database’s fine, client’s screaming. Let’s reproduce it and fix it properly. Reproducing It lsnrctl stop sqlplus system@ORCL Boom. Same error. No ma...