=== ④ 문서가 적은 형태 그대로 ===
(위가 비면 아래를 본다)
=== 더 넓게 ===
2026-09-17 06:11:31,802 WARN  [org.keycloak.jgroups.protocol.KEYCLOAK_JDBC_PING2] (blocking-thread--p3-t2) Failed to fetch the cluster members from the database.: org.postgresql.util.PSQLException: FATAL: terminating connection due to administrator command
2026-09-17 06:11:59,291 ERROR [org.keycloak.services] (executor-thread-3) KC-SERVICES0015: Unexpected error when authenticating client: org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection [Connection to postgres:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.] [n/a]
=== 실제로 찍힌 오류 줄 ===
2026-09-17 06:11:49,114 ERROR [org.keycloak.jgroups.protocol.KEYCLOAK_JDBC_PING2] (Timer runner-2,keycloak-0-44929(v=16.0.12)) keycloak-0-44929(v=16.0.12): failed reading from the DB: org.postgresql.util.PSQLException: Connection to postgres:5432 refused. Chec
2026-09-17 06:11:55,190 ERROR [org.keycloak.jgroups.protocol.KEYCLOAK_JDBC_PING2] (Timer runner-2,keycloak-0-44929(v=16.0.12)) keycloak-0-44929(v=16.0.12): failed writing to DB: org.postgresql.util.PSQLException: Connection to postgres:5432 refused. Check that
2026-09-17 06:11:59,291 ERROR [org.keycloak.services] (executor-thread-3) KC-SERVICES0015: Unexpected error when authenticating client: org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection [Connection to postgres:5432 refused. Che
2026-09-17 06:11:59,295 WARN  [org.keycloak.events] (executor-thread-3) type="LOGIN_ERROR", realmId="f9bed085-ff57-4ab0-92ab-af83adeb320e", realmName="master", clientId="admin-cli", userId="null", ipAddress="10.42.1.42", error="invalid_client_credentials", gra
