连接时报错：
[oracle@yangtk2 ~]$ lsnrctl status
LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 01-SEP-2008 17:36:03
Copyright (c) 1991, 2007, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.1.0.6.0 - Production
Start Date 01-SEP-2008 17:01:31
Uptime 0 days 0 hr. 34 min. 32 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /data/oracle/product/11.1/network/admin/listener.ora
Listener Log File /data/oracle/diag/tnslsnr/yangtk2/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.25.1.104)(PORT=1521)))
The listener supports no services
The command completed successfully
检查listener.ora和tnsnames.ora都未发现异常：
[oracle@yangtk2 admin]$ more listener.ora
# listener.ora Network Configuration File: /data/oracle/product/11.1/network/admin/listener.ora
# Generated by Oracle configuration tools.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.25.1.104)(PORT = 1521))
)
)
[oracle@yangtk2 admin]$ more tnsnames.ora
# tnsnames.ora Network Configuration File: /data/oracle/product/11.1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
ORA11G_S =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.25.1.104)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = ora11g_s.ytk-thinkpad)
)
)
ORA11G_P =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.25.1.102)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = ora11g_p.ytk-thinkpad)
)
)
而且以前这个配置没有任何问题，就是这次启动虚机后才出现的问题。
查询了metalink，虽然上面记载了很多ORA-12514错误，但是没有发现什么有帮助的线索。
由于这个错误以前并没有出现，所以怀疑是最近修改了什么东西导致了这个问题。而启动之后做了唯一的修改就是修改了主机的IP地址。
通过ifconfig修改了主机IP地址，莫非是修改错误导致了问题，不过现在通过IP地址可以正常的登陆主机，而且tnsping也没有任何的问题：
[oracle@yangtk2 admin]$ tnsping ora11g_s
TNS Ping Utility for Linux: Version 11.1.0.6.0 - Production on 01-SEP-2008 17:54:31
Copyright (c) 1997, 2007, Oracle. All rights reserved.
Used parameter files:
/data/oracle/product/11.1/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.25.1.104)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = ora11g_s.ytk-thinkpad)))
OK (0 msec)
最后检查listner的日志：
[oracle@yangtk2 admin]$ tail -20 /data/oracle/diag/tnslsnr/yangtk2/listener/alert/log.xml
type='UNKNOWN' level='16' host_id='yangtk2.ytk-thinkpad'
host_addr='172.25.4.70'>
01-SEP-2008 17:54:31 * ping * 0
type='UNKNOWN' level='16' host_id='yangtk2.ytk-thinkpad'
host_addr='172.25.4.70'>
WARNING: Subscription for node down event still pending
type='UNKNOWN' level='16' host_id='yangtk2.ytk-thinkpad'
host_addr='172.25.4.70'>
01-SEP-2008 17:58:24 * (CONNECT_DATA=(CID=(PROGRAM=)(HOST=yangtk2.ytk-thinkpad)(USER=oracle))(COMMAND=status)(ARGUMENTS=64)(SERVICE=LISTENER)(VERSION=185599488)) * status * 0
发现日志中的IP地址并没有改变，看来是修改IP的时候遗漏了什么位置。
检查HOSTS文件，发现里面的配置忘了进行修改：
[oracle@yangtk2 admin]$ more /etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
172.25.4.70 yangtk2.ytk-thinkpad
127.0.0.1 localhost.localdomain localhost
将hosts文件中的ip也修改为当前的IP后，问题解决
[oracle@yangtk2 ~]$ lsnrctl stop
LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 01-SEP-2008 18:01:00
Copyright (c) 1991, 2007, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
The command completed successfully
[oracle@yangtk2 ~]$ lsnrctl start
LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 01-SEP-2008 18:01:10
Copyright (c) 1991, 2007, Oracle. All rights reserved.
Starting /data/oracle/product/11.1/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.1.0.6.0 - Production
System parameter file is /data/oracle/product/11.1/network/admin/listener.ora
Log messages written to /data/oracle/diag/tnslsnr/yangtk2/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.25.1.104)(PORT=1521)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.1.0.6.0 - Production
Start Date 01-SEP-2008 18:01:10
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /data/oracle/product/11.1/network/admin/listener.ora
Listener Log File /data/oracle/diag/tnslsnr/yangtk2/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.25.1.104)(PORT=1521)))
The listener supports no services
The command completed successfully
稍等一会，通过sqlplus连接数据库：
[oracle@yangtk2 ~]$ sqlplus sys/test@ora11g_s as sysdba
SQL*Plus: Release 11.1.0.6.0 - Production on Mon Sep 1 18:03:16 2008
Copyright (c) 1982, 2007, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL>