ORA-00443: background process "MMNL" did not start

数据库启动报错：

SYS@PROD1> startup
ORACLE instance started.

Total System Global Area  521936896 bytes
Fixed Size                  2254824 bytes
Variable Size             381683736 bytes
Database Buffers          130023424 bytes
Redo Buffers                7974912 bytes
Database mounted.
ORA-01013: user requested cancel of current operation

尝试解决：

SYS@PROD1> shutdown immediate;

SYS@PROD1> alter database mount;
Database altered.
SYS@PROD1> alter database open ;
Database altered.
SYS@PROD1> select status from v$instance;


STATUS
------------------------------------
OPEN