How to clean Archive logs

Question

Oralce 12c ASM How to clean Archive logs. Oracle Instance is NOT starting since Archive disk group is full, This is my TEST DB I don't want to extend the diskgroup so instead I would like to DELETE ALL archive logs.

SQL> startup
ORACLE instance started.

Total System Global Area  738197504 bytes
Fixed Size                  2928776 bytes
Variable Size             314576760 bytes
Database Buffers          415236096 bytes
Redo Buffers                5455872 bytes
Database mounted.
ORA-03113: end-of-file on communication channel
Process ID: 31849
Session ID: 124 Serial number: 41214

Alert logs

> NOTE: Assigning number (1,0) to disk (/dev/DG-DISK3) SUCCESS: mounted
> group 1 (ARCH) NOTE: grp 1 disk 0: ARCH_0000 path:/dev/DG-DISK3 Wed
> Aug 24 03:50:11 2016 Unable to create archive log file '+ARCH' Wed Aug
> 24 03:50:11 2016 Errors in file
> /u01/app/oracle/diag/rdbms/asmdb1/ASMDB1/trace/ASMDB1_ora_338.trc:
> ORA-19504: failed to create file "+ARCH" ORA-17502: ksfdcre:4 Failed
> to create file +ARCH ORA-15041: diskgroup "ARCH" space exhausted ARCH:
> Error 19504 Creating archive log file to '+ARCH' Wed Aug 24 03:50:11
> 2016 Errors in file
> /u01/app/oracle/diag/rdbms/asmdb1/ASMDB1/trace/ASMDB1_ora_338.trc:
> ORA-16038: log 2 sequence# 143 cannot be archived ORA-19504: failed to
> create file "" ORA-00312: online log 2 thread 1:
> '+DATA/ASMDB1/ONLINELOG/group_2.262.917061333' USER (ospid: 338):
> terminating the instance due to error 16038 Wed Aug 24 03:50:11 2016
> System state dump requested by (instance=1, osid=338),
> summary=[abnormal instance termination]. System State dumped to trace
> file
> /u01/app/oracle/diag/rdbms/asmdb1/ASMDB1/trace/ASMDB1_diag_32746_20160824035011.trc
> Wed Aug 24 03:50:11 2016 Dumping diagnostic data in
> directory=[cdmp_20160824035011], requested by (instance=1, osid=338),
> summary=[abnormal instance termination]. Wed Aug 24 03:50:12 2016
> Instance terminated by USER, pid = 338

Answer 1

Start the instance in MOUNT mode, delete the logs, then open the database.

$ rman target /

RMAN> startup mount
RMAN> delete force noprompt archivelog all;
RMAN> alter database open;