Why my Oracle 12c database seems not to be started?

I have installed an Oracle 12c database on my development environment, which I start only once a while for integration testing. But today, it does not seem to start, or did it start but does not allow connections? Here are some clues: - OS is Debian 8 - I use a shell script to start and stop the database - **$ORACLE_SID** contains > INFO - The **hosts** file contains > 127.0.0.1 localhost and 127.0.1.1 Strada.nohoo.biz Strada - The **/u01/app/oracle/diag/rdbms/info/INFO/alert_INFO.log** file ends with > Completed: ALTER DATABASE OPEN Sun Mar 11 20:27:57 2018 Shared IO Pool > defaulting to 112MB. Trying to get it from Buffer Cache for process > 4294. > =========================================================== Dumping current patch information > =========================================================== No patches have been applied > =========================================================== Sun Mar 11 20:27:57 2018 db_recovery_file_dest_size of 4560 MB is 0.00% used. > This is a user-specified limit on the amount of space that will be > used by this database for recovery-related files, and does not reflect > the amount of space available in the underlying filesystem or ASM > diskgroup. - **tnsping** INFO returns > TNS Ping Utility for Linux: Version 12.1.0.2.0 - Production on > 11-MAR-2018 21:42:22 > > Copyright (c) 1997, 2014, Oracle. All rights reserved. > > Used parameter files: > /u01/app/oracle/product/12.1.0/dbhome_1/network/admin/sqlnet.ora > > > Used TNSNAMES adapter to resolve the alias Attempting to contact > (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = > 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = > INFO.nohoo.biz))) > > OK (0 msec) - **tnsnames.ora** contains > INFO = > (DESCRIPTION = > (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)) > (CONNECT_DATA = > (SERVER = DEDICATED) > (SERVICE_NAME = INFO.nohoo.biz) > ) > ) - **listner.ora** contains > LISTENER = > (DESCRIPTION_LIST = > (DESCRIPTION = > (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)) > (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521)) > ) > ) - **lsnrctl services** returns > LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 11-MAR-2018 > 21:54:24 > > Copyright (c) 1991, 2014, Oracle. All rights reserved. > > Connecting to > (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521))) > > The listener supports no services > > > The command completed successfully - The **ps -A | grep ora** command in a shell returns a list of > 6003 ? 00:00:00 ora_pmon_info > 6005 ? 00:00:00 ora_psp0_info > 6007 ? 00:00:00 ora_vktm_info > 6011 ? 00:00:00 ora_gen0_info > 6013 ? 00:00:00 ora_mman_info > 6017 ? 00:00:00 ora_diag_info > 6019 ? 00:00:00 ora_dbrm_info > 6021 ? 00:00:00 ora_vkrm_info > 6023 ? 00:00:00 ora_dia0_info > 6025 ? 00:00:00 ora_dbw0_info > 6027 ? 00:00:00 ora_lgwr_info > 6029 ? 00:00:00 ora_ckpt_info But all this does not look like a successful situation! And finally, trying to connect with SQLplus ends up with > ORA-12547: TNS:lost contact Thanks for you help!