合 ipcs、ipcrm和sysresv在Oracle中的使用
前言部分
导读和注意事项
各位技术爱好者，看完本文后，你可以掌握如下的技能，也可以学到一些其它你所不知道的知识，~O(∩_∩)O~：
① ipcs的使用
② ipcrm释放oracle内存段
③ sysresv的使用
本文简介
同事搭建DG的时候报错了，然后强制退出会话，结果sqlplus不能进入，且看正文部分。
相关知识点扫盲
unix/linux下的共享内存、信号量、队列信息管理
在unix/linux下，经常有因为共享内存、信号量，队列等共享信息没有干净地清楚而引起一些问题。
查看共享信息的内存的命令是ipcs [-m|-s|-q]。
默认会列出共享内存、信号量，队列信息，-m列出共享内存，-s列出共享信号量，-q列出共享队列
清除命令是ipcrm [-m|-s|-q] id。
-m 删除共享内存，-s删除共享信号量，-q删除共享队列。
故障分析及解决过程
故障环境介绍
| 项目 | source db |
|---|---|
| db 类型 | rac |
| db version | 11.2.0.4 |
| db 存储 | ASM |
| ORACLE_SID | oraDESDB2 |
| db_name | oraDESDB |
| OS版本及kernel版本 | AIX 64位 7.1.0.0 |
| OS hostname | ZFLHRDB2 |
故障发生现象及解决过程
oracle的进程已经关闭，但是执行sqlplus的时候hang住，之后报错ORA-09925: Unable to create audit trail file，加-prelim也不行，主要是oracle的进程已经关掉了，但是sqlplus却进不去。
ZFLHRDB4:oracle:/oracle>ps -ef|grep ora_
ZFLHRDB4:oracle:/oracle>sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Tue May 31 14:39:47 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
ERROR:
ORA-09925: Unable to create audit trail file
IBM AIX RISC System/6000 Error: 2: No such file or directory
Additional information: 9925
ORA-09925: Unable to create audit trail file
IBM AIX RISC System/6000 Error: 2: No such file or directory
Additional information: 9925
ZFLHRDB4:oracle:/oracle>sqlplus -prelim / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Tue May 31 14:40:26 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
ERROR:
ORA-09925: Unable to create audit trail file
IBM AIX RISC System/6000 Error: 2: No such file or directory
Additional information: 9925
ORA-09925: Unable to create audit trail file
IBM AIX RISC System/6000 Error: 2: No such file or directory
Additional information: 9925
IPC status from /dev/mem as of Tue May 31 14:42:01 BEIST 2016
T ID KEY MODE OWNER GROUP
Message Queues:
q 0 0x9283a0d2 -Rrw------- root system
q 1 0xffffffff ----------- root system
Shared Memory:
m 3 0x210000ac --rw-rw---- root system
m 395313156 0x0ecaefdc --rw-r----- oracle asmadmin
m 9437189 00000000 --rw-r----- oracle asmadmin
m 276824070 00000000 --rw-r----- oracle asmadmin
m 912261127 0x210000d4 --rw-rw---- grid dba
Semaphores:
s 3145728 0x0100324a --ra-ra-r-- root system
s 1 0x620025b4 --ra-r--r-- root system
s 2 0x02001958 --ra-ra-ra- root system
s 3 0x01001958 --ra-ra-ra- root system
s 9 0x010024be --ra------- root system
s 3145738 0x410000ab --ra-ra---- root system
s 21 0x410000cb --ra-ra---- grid dba
ZFLHRDB4:oracle:/oracle>ipcrm -m 395313156
IPC status from /dev/mem as of Tue May 31 14:42:23 BEIST 2016
T ID KEY MODE OWNER GROUP
Message Queues:
q 0 0x9283a0d2 -Rrw------- root system
q 1 0xffffffff ----------- root system
Shared Memory:
m 3 0x210000ac --rw-rw---- root system
m 9437189 00000000 --rw-r----- oracle asmadmin
m 276824070 00000000 --rw-r----- oracle asmadmin
m 912261127 0x210000d4 --rw-rw---- grid dba
Semaphores:
s 3145728 0x0100324a --ra-ra-r-- root system
s 1 0x620025b4 --ra-r--r-- root system
s 2 0x02001958 --ra-ra-ra- root system
s 3 0x01001958 --ra-ra-ra- root system
s 9 0x010024be --ra------- root system
s 3145738 0x410000ab --ra-ra---- root system
s 21 0x410000cb --ra-ra---- grid dba
ZFLHRDB4:oracle:/oracle>ipcrm -m 9437189
ZFLHRDB4:oracle:/oracle>ipcrm -m 276824070
IPC status from /dev/mem as of Tue May 31 14:42:39 BEIST 2016
T ID KEY MODE OWNER GROUP
Message Queues:
q 0 0x9283a0d2 -Rrw------- root system
q 1 0xffffffff ----------- root system
Shared Memory:
m 3 0x210000ac --rw-rw---- root system
m 912261127 0x210000d4 --rw-rw---- grid dba
Semaphores:
s 3145728 0x0100324a --ra-ra-r-- root system
s 1 0x620025b4 --ra-r--r-- root system
s 2 0x02001958 --ra-ra-ra- root system
s 3 0x01001958 --ra-ra-ra- root system
s 9 0x010024be --ra------- root system
s 3145738 0x410000ab --ra-ra---- root system
s 21 0x410000cb --ra-ra---- grid dba
ZFLHRDB4:oracle:/oracle>sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Tue May 31 14:42:46 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SYS@oraDESDB2>
问题解决了，但是为啥会出现这样的错误，我在MOS上搜了以下的文章。
MOS上的文件
---Connect /as sysdba or Startup Fails With ORA-09925 When Instance Is Down (文档 ID 392643.1)
In this Document
Symptoms
Cause
Solution
References
APPLIES TO:
Oracle Database - Enterprise Edition - Version 8.1.7.0 to 12.1.0.1 [Release 8.1.7 to 12.1]
Information in this document applies to any platform.
Checked for relevance on 05-Oct-2010
SYMPTOMS
When the database instance is down, trying to connect or startup the database fails with:
ERROR:
ORA-09925: Unable to create audit trail file
SVR4 Error: 13: Permission denied
Additional information: 9925
CAUSE
On Unix systems, the investigation should be done using the OS tracing utility, ie: truss (AIX, Solaris), strace (Linux) or tusc (HP-UX).
truss -aefo sqlplus.trc sqlplus "/ as sysdba"
shows that the problem is caused by a missing directory, insufficient permissions or not enough space on that particular directory:
open("/opt/oracle/admin/test102/adump/ora_31704.aud", O_RDWR|O_CREAT|O_APPEND|O_LARGEFILE, 0660) = -1 EACCES (Permission denied)
From 10gR2, the $ORACLE_BASE/admin/\<SID>/adump directory is the new default directory for audit files (instead of previous releases location, $ORACLE_HOME/rdbms/audit).
SOLUTION
1. Starting with 10gR2, check if the
$ORACLE_BASE/admin/$ORACLE_SID/adump
directory exists and create it if not.
If ORACLE_BASE is not set, the default audit directory is still $ORACLE_HOME/rdbms/audit, as in pre 10gR2 releases.
2. If the directory exists (if in previous releases or if ORACLE_BASE not set, check: $ORACLE_HOME/rdbms/audit), make sure that permissions on it are set to 775.
3. If the directory exists and permissions are correctly set, make sure that there is enough space on the file system to accommodate the newly created audit files.
Starting with 10gR2: Note that when the database instance is down and the first connect and the startup command is run, the audit_file_dest parameter is not yet initialized, hence unknown to the shadow process, as such the audit files for these commands can only be written to the default destination. Writing these files is a mandatory requirement for NCSC C2 security evaluation criteria and therefore this behavior cannot be turned off.
4. Generically, ORACLE_BASE is set, as recommended by the documentation. If ORACLE_BASE is not set, then the default audit location becomes: $ORACLE_HOME/rdbms/audit. This is important to mention especially on RAC, where the environment variables are set in the OCR and should be updated, as documented, using srvctl, eg:
srvctl setenv database -d \<db name> -t ORACLE_BASE=\<Oracle Base directory>
5. A rare scenario was found when ORACLE_PATH is set and the Oracle software transparently appended it to the default value: $ORACLE_BASE/admin/$ORACLE_SID/adump. ORACLE_PATH needs to be unset to workaround the problem. This issue was found to be a regression in the fix to bug 9438890 , and can be fixed by installing patch 14488943.
---ORA-09925 : Error During Database Creation Using Other OS Users. (文档 ID 405885.1)
In this Document
Symptoms
Cause
Solution
This document is being delivered to you via Oracle Support's Rapid Visibility (RaV) process and therefore has not been subject to an independent technical review.
APPLIES TO:
Oracle Server - Enterprise Edition - Version 9.2.0.1 and later
Linux x86
HP-UX PA-RISC (64-bit)
IBM AIX on POWER Systems (64-bit)
Oracle Solaris on SPARC (64-bit)
Linux x86-64
***Checked for relevance on 19-Jun-2012***
SYMPTOMS
Creating database using DBCA logged in as another user belonging to the installation group results in following error
ORA-09925 : Unable to create audit trail file.
If you ignore this error it will error out with following message
ORA-01034 : Oracle not available.
CAUSE
By default Oracle will create directories with permission 755. So the other users belonging to the group will not have write permission which results in this issue.
SOLUTION
Any user other than the software owner belonging to the same group will not be able to create database.
To resolve the issue give write permission to the group on following directories.
1. chmod 775 $ORACLE_HOME/audit
2. chmod 775 $ORACLE_HOME/cfgtoollogs/dbca
3. Give write permission on directories where data files and control files are getting created.
4. Give write permission on $ORACLE_BASE
5. chgrp \<oracle group> /etc/oratab
Note: This holds good for other Unix platforms as well.
---OS AUDIT ERROR IN ASM AND ORA-09925 in RDBMS (文档 ID 1921650.1)
In this Document
Symptoms
Cause
Solution
References
APPLIES TO:
Oracle Database - Enterprise Edition - Version 11.2.0.3 to 11.2.0.4 [Release 11.2]
Information in this document applies to any platform.
SYMPTOMS
1] The following error message is reported in ASM alert.log
OS Audit file could not be created; failing after x retries
2] The following similar message is visible in RDBMS alert.log
