sqlplus 连接oracle报 ORA-01041: internal error. hostdef extension doesn't exist

问题现象如下
 

[oracle@tyj ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Tue Jan 22 21:56:28 2019

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

ERROR:
ORA-01041: internal error. hostdef extension doesn't exist


Enter user-name: 
ERROR:
ORA-01017: invalid username/password; logon denied


Enter user-name: 
ERROR:
ORA-01017: invalid username/password; logon denied


SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus
[oracle@tyj ~]$ sqlplus /nolog

SQL*Plus: Release 11.2.0.1.0 Production on Tue Jan 22 21:56:39 2019

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

SQL> conn /as sysdba
ERROR:
ORA-01041: internal error. hostdef extension doesn't exist


SQL> exit

这种情况有可能是共享内存问题导致的

[oracle@tyj ~]$ ipcs -mpt   --查看共享内存

------ Shared Memory Attach/Detach/Change Times --------
shmid      owner      attached             detached             changed             
65537      oracle     Jan 22 21:56:44      Jan 22 21:56:44      Jan 22 16:59:24 

[oracle@tyj ~]$ sysresv -l dspdb   ---查看与实例名关联的共享内存

IPC Resources for ORACLE_SID "dspdb" :
Shared Memory:
ID		KEY
65537   	0x95bfdcbc    --就是这里
Semaphores:
ID		KEY
163842  	0x6874b294
196611  	0x6874b295
229380  	0x6874b296
262149  	0x6874b297
294918  	0x6874b298
327687  	0x6874b299
360456  	0x6874b29a
393225  	0x6874b29b
425994  	0x6874b29c
Oracle Instance alive for sid "dspdb"
[oracle@tyj bin]$ ipcrm -m 65537     --用ipcrm命令删除
[oracle@tyj bin]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Tue Jan 22 22:50:40 2019

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

Connected to an idle instance.

SQL> 

搞定了，详细参考这篇文章：https://oracle-base.com/articles/misc/ora-01041-internal-error-hostdef-extension-doesnt-exist