ORA-01034: ORACLE not available Process ID: 0 Session ID: 0 Serial number: 0

linux上登錄Oracle，輸入''select 1 from dual"，出現如下報錯信息：

SQL> select 1 from dual;
select 1 from dual
*
ERROR at line 1:
ORA-01034: ORACLE not available
Process ID: 0
Session ID: 0 Serial number: 0

1.檢查listener是否運行正常

2.以管理員角色登錄，輸入以下命令。因爲之前歸檔文件滿了，還報錯：ORA-03113: end-of-file on communication channel，所以增加了閃回區大小，具體操作如下：

[oracle@localhost ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Tue Dec 17 16:35:56 2019

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> shutdown abort
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.

Total System Global Area  521936896 bytes
Fixed Size		    2214936 bytes
Variable Size		  499123176 bytes
Database Buffers	   16777216 bytes
Redo Buffers		    3821568 bytes
Database mounted.
SQL> show parameter db_recovery_file_dest_size;

NAME				     TYPE
------------------------------------ ---------------------------------
VALUE
------------------------------
db_recovery_file_dest_size	     big integer
10G

SQL> alter system set db_recovery_file_dest_size=15G;

System altered.

SQL> alter database open;

Database altered.

SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup;
ORACLE instance started.

Total System Global Area  521936896 bytes
Fixed Size		    2214936 bytes
Variable Size		  499123176 bytes
Database Buffers	   16777216 bytes
Redo Buffers		    3821568 bytes
Database mounted.
Database opened.