數據庫使用一個月了，突然掛掉：錯誤代碼17002 io異常:read timeout
解決：
1.登陸sql命令窗口
[oracle@hostname ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Fri Aug 28 10:58:59 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
2.以管理員身份連接到數據庫
SQL> connect sys/oracle as sysdba
Connected.
3.關閉數據庫實例
SQL> shutdown abort
ORACLE instance shut down.
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
4.查看監聽並關閉
[oracle@hostname~]$ lsnrctl status
[oracle@hostname~]$ lsnrctl stop
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 28-AUG-2015 11:15:32
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=iZ11gqfg6h1Z)(PORT=1521)))
The command completed successfully
5.重啟監聽
[oracle@hostname~]$ lsnrctl start
6.重啟數據庫
[oracle@hostname~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Fri Aug 28 11:30:25 2015
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> connect / as sysdba
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 1486495744 bytes
Fixed Size 2213496 bytes
Variable Size 1124075912 bytes
Database Buffers 352321536 bytes
Redo Buffers 7884800 bytes
Database mounted.
Database opened.
特別需要注意的是，一定要先啟動監聽服務，再啟動數據庫，否則還是連不上的。
查看oracle 數據庫服務：lsnrctl status