【故障解決】IPCS和IPCRM使用

【故障解決】IPCS和IPCRM使用

1.1 BLOG文件結構圖

1.2 前言部分

1.2.1 導讀和注意事項

各位技術愛好者，看完本文後，你可以掌握如下的技能，也可以學到一些其它你所不知道的知識，~O(∩_∩)O~：

① ipcs的使用

② ipcrm釋放oracle記憶體段

③ sysresv的使用

Tips：

① 若文章程式碼格式有錯亂，推薦使用搜狗、QQ或360瀏覽器，也可以下載pdf格式的文件來檢視，pdf文件下載地址：http://yunpan.cn/cdEQedhCs2kFz （提取碼：ed9b）

② 本篇BLOG中命令的輸出部分需要特別關注的地方我都用灰色背景和粉紅色字型來表示，比如下邊的例子中，thread 1的最大歸檔日誌號為33，thread 2的最大歸檔日誌號為43是需要特別關注的地方；而命令一般使用黃色背景和紅色字型標注；對程式碼或程式碼輸出部分的注釋一般採用藍色字型表示。

List of Archived Logs in backup set 11

Thrd Seq Low SCN Low Time Next SCN Next Time

---- ------- ---------- ------------------- ---------- ---------

1 32 1621589 2015-05-29 11:09:52 1625242 2015-05-29 11:15:48

1 33 1625242 2015-05-29 11:15:48 1625293 2015-05-29 11:15:58

2 42 1613951 2015-05-29 10:41:18 1625245 2015-05-29 11:15:49

2 43 1625245 2015-05-29 11:15:49 1625253 2015-05-29 11:15:53

[ZFXXDB1:root]:/>lsvg -o

T_XDESK_APP1_vg

rootvg

[ZFXXDB1:root]:/>

00:27:22 SQL> alter tablespace idxtbs read write;

====》2097152*512/1024/1024/1024=1G

本文如有錯誤或不完善的地方請大家多多指正，ITPUB留言或QQ皆可，您的批評指正是我寫作的最大動力。

http://blog.itpub.net/26736162/viewspace-2112447/

1.2.3 本文簡介

同事搭建DG的時候報錯了，然後強制退出會話，結果sqlplus不能進入，且看正文部分。

1.3 相關知識點掃盲

unix/linux下的共享記憶體、訊號量、佇列資訊管理
在unix/linux下，經常有因為共享記憶體、訊號量，佇列等共享資訊沒有乾淨地清楚而引起一些問題。
檢視共享資訊的記憶體的命令是ipcs [-m|-s|-q]。

預設會列出共享記憶體、訊號量，佇列資訊，-m列出共享記憶體，-s列出共享訊號量，-q列出共享佇列
清除命令是ipcrm [-m|-s|-q] id。
-m 刪除共享記憶體，-s刪除共享訊號量，-q刪除共享佇列。

1.4 故障分析及解決過程

1.4.1 故障環境介紹

專案	source db
db 型別	rac
db version	11.2.0.4
db 儲存	ASM
ORACLE_SID	oraDESDB2
db_name	oraDESDB
OS版本及kernel版本	AIX 64位 7.1.0.0
OS hostname	ZFLHRDB2

1.4.2 故障發生現象及解決過程

oracle的程式已經關閉，但是執行sqlplus的時候hang住，之後報錯ORA-09925: Unable to create audit trail file，加-prelim也不行，主要是oracle的程式已經關掉了，但是sqlplus卻進不去。

[ZFLHRDB4:oracle]:/oracle>ps -ef|grep ora_

[ZFLHRDB4:oracle]:/oracle>

[ZFLHRDB4:oracle]:/oracle>sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Tue May 31 14:39:47 2016

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>

[ZFLHRDB4:oracle]:/oracle>sqlplus -prelim / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Tue May 31 14:40:26 2016

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>ipcs

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

[ZFLHRDB4:oracle]:/oracle>ipcs

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

[ZFLHRDB4:oracle]:/oracle>ipcs

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

Connected to an idle instance.

SYS@oraDESDB2>

問題解決了，但是為啥會出現這樣的錯誤，我在MOS上搜了以下的文章。

1.4.2.1 MOS上的檔案

---Connect /as sysdba or Startup Fails With ORA-09925 When Instance Is Down (文件 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//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 -t ORACLE_BASE=

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. (文件 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 /etc/oratab

Note: This holds good for other Unix platforms as well.

---OS AUDIT ERROR IN ASM AND ORA-09925 in RDBMS (文件 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

Additional information: 9925

ORA-01122: database file 5 failed verification check

ORA-01110: data file 5: '+DATA/asmdb/datafile/rcts.343.849109407'

ORA-01565: error in identifying file '+DATA/asmdb/datafile/rcts.343.849109407'

ORA-17503: ksfdopn:2 Failed to open file +DATA/asmdb/datafile/rcts.343.849109407

ORA-15055: unable to connect to ASM instance

ORA-09925: Unable to create audit trail file

Linux-x86_64 Error: 13: Permission denied

Additional information: 9925

NOTE: deferred map free for map id 180

WARNING: ASM communication error: op 18 state 0x40 (9925)

ERROR: slave communication error with ASM

NOTE: Deferred communication with ASM instance

Errors in file /u01/app/oracle/diag/rdbms/asmdb/ASMDB/trace/ASMDB_pmon_3692.trc:

ORA-09925: Unable to create audit trail file

Linux-x86_64 Error: 13: Permission denied

Additional information: 9925

WARNING: ASM communication error: op 0 state 0x0 (15055)

ERROR: direct connection failure with ASM

3] Logging in ASM instance produces the following error.

$ sqlplus / as sysasm

ERROR:

ORA-09925: Unable to create audit trail file

Linux-x86_64 Error: 13: Permission denied

Additional information: 9925

ORA-01075: you are currently logged on

4] Filesystem for GRID home shows enough space

# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/host_root

9.7G 1.8G 7.5G 19% /

/dev/mapper/host_var

4.9G 923M 3.7G 20% /var

/dev/mapper/host_usr

4.9G 3.4G 1.3G 74% /usr

/dev/mapper/host_crs_oracle

54G 23G 28G 46% /crs/oracle <<<<<<<<<------------ GRID HOME filesystem

CAUSE

Permission on GRID_HOME/rdbms/audit was incorrect.

$ ls -l $GRID_HOME/rdbms

drwxr-xr-x. 2 grid oinstall 40960 Jul 31 15:01 admin

dr-xr-xr-x. 2 grid oinstall 12288 Aug 26 08:13 audit <<<<<<------ Here, there is no write privilege by grid OS user.

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 14:59 demo

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 14:59 doc

drwxr-xr-x. 4 grid oinstall 4096 Jul 31 15:01 install

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 14:57 jlib

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 15:01 lib

drwxr-xr-x. 2 grid oinstall 4096 Aug 24 08:05 log

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 14:57 mesg

drwxr-xr-x. 2 grid oinstall 4096 Jul 31 14:57 public

drwxr-xr-x. 5 grid oinstall 4096 Jul 31 14:56 xml

SOLUTION

1] Change the permission so that grid OS user can write on $GRID_HOME/rdbms/audit

As grid OS user:

$ chmod +w $GRID_HOME/rdbms/audit

2] Check whether enough free space exists on GRID_HOME filesystem

SQL> show parameter dest

NAME TYPE VALUE

------------------------------------ ---------------------- ------------------------------

audit_file_dest string /oracle/app/11.2.0/grid/rdbms/

audit

background_dump_dest string /oracle/app/grid/diag/asm/+asm

/+ASM2/trace

core_dump_dest string /oracle/app/grid/diag/asm/+asm

/+ASM2/cdump

diagnostic_dest string /oracle/app/grid

user_dump_dest string /oracle/app/grid/diag/asm/+asm

/+ASM2/trace

SQL> exit

Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

With the Real Application Clusters and Automatic Storage Management options

[ZFLHRDB2:grid]:/oracle/app/grid>cd /oracle/app/11.2.0/grid/rdbms/audit

[ZFLHRDB2:grid]:/oracle/app/11.2.0/grid/rdbms/audit>l

[ZFLHRDB2:grid]:/oracle/app/11.2.0/grid/rdbms/audit>ls | wc -l

42828

[ZFLHRDB2:grid]:/oracle/app/11.2.0/grid/rdbms/audit>rm -rf *

ksh: /usr/bin/rm: 0403-027 The parameter list is too long.

[ZFLHRDB2:grid]:/oracle/app/11.2.0/grid/rdbms/audit>find . -name "*.aud" | xargs rm

[ZFLHRDB2:grid]:/oracle/app/11.2.0/grid/rdbms/audit>ls

[ZFLHRDB2:root]:/oracle/app/11.2.0/grid/rdbms>chmod 775 audit

[ZFLHRDB2:root]:/oracle/app/11.2.0/grid/rdbms>l

total 176

drwxr-xr-x 2 grid dba 53248 Dec 23 2014 admin

drwxrwxr-x 2 grid dba 256 Jun 01 09:47 audit

drwxr-xr-x 2 grid dba 256 Nov 05 2014 demo

drwxr-xr-x 2 grid dba 256 Nov 05 2014 doc

drwxr-xr-x 4 grid dba 4096 Nov 05 2014 install

drwxr-xr-x 2 grid dba 4096 Nov 05 2014 jlib

drwxr-xr-x 2 grid dba 8192 Dec 23 2014 lib

drwxr-xr-x 2 grid dba 4096 May 31 19:02 log

drwxr-xr-x 2 grid dba 8192 Nov 05 2014 mesg

drwxr-xr-x 2 grid dba 256 Nov 05 2014 public

drwxr-xr-x 5 grid dba 4096 Nov 05 2014 xml

[ZFLHRDB2:root]:/oracle/app/11.2.0/grid/rdbms>

1.4.3 ipcs命令擴充套件

MOS上的幾篇文章：

其中68281.1中提到DETERMINING WHICH INSTANCE OWNS WHICH SHARED MEMORY SEGMENTS & SEMAPHORE SETS，即若是一個主機上有多個oracle例項的話該如何確定哪個共享記憶體段屬於我們該清掉的oracle例項的記憶體段，下邊給個小實驗即可，相關的MOS文件可以去小麥苗的雲盤下載。

[ZFXDESKDB2:oracle]:/oracle>ps -ef|grep ora_pmon_

oracle 12255344 21626964 0 17:43:01 pts/0 0:00 grep ora_pmon_

oracle 17629238 1 0 18:57:42 - 0:09 ora_pmon_raclhr2

oracle 20250806 1 0 18:57:42 - 0:10 ora_pmon_oraESKDB2

[ZFXDESKDB2:oracle]:/oracle>which sysresv

/oracle/app/oracle/product/11.2.0/db/bin/sysresv

[ZFXDESKDB2:oracle]:/oracle>ORACLE_SID=raclhr2

[ZFXDESKDB2:oracle]:/oracle>sysresv

IPC Resources for ORACLE_SID "raclhr2" :

Shared Memory:

ID KEY

5242886 0xffffffff

5242883 0xffffffff

1048583 0xd92489e0

Oracle Instance alive for sid "raclhr2"

[ZFXDESKDB2:oracle]:/oracle>ipcs

IPC status from /dev/mem as of Wed Jun 1 17:43:47 BEIST 2016

T ID KEY MODE OWNER GROUP

Message Queues:

q 0 0x9283a0d2 -Rrw------- root system

q 1 0xffffffff ----------- root system

Shared Memory:

m 1048576 00000000 --rw-r----- grid dba

m 1048577 00000000 --rw-r----- grid dba

m 1048578 0x210000aa --rw-rw---- root system

m 5242883 00000000 --rw-r----- oracle asmadmin

m 1048580 00000000 --rw-r----- oracle asmadmin

m 1048581 00000000 --rw-r----- oracle asmadmin

m 5242886 00000000 --rw-r----- oracle asmadmin

m 1048583 0xd92489e0 --rw-r----- oracle asmadmin

m 1048584 0xd1a4a5d8 --rw-r----- grid dba

m 8388617 0x3f516768 --rw-r----- oracle asmadmin

m 759169034 0x21000148 --rw-rw---- oracle 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 1048590 0x410000a8 --ra-ra---- root system

s 11534361 0x41000147 --ra-ra---- oracle dba

[ZFXDESKDB2:oracle]:/oracle>ipcs -m

IPC status from /dev/mem as of Wed Jun 1 17:43:56 BEIST 2016

T ID KEY MODE OWNER GROUP

Shared Memory:

m 1048576 00000000 --rw-r----- grid dba

m 1048577 00000000 --rw-r----- grid dba

m 1048578 0x210000aa --rw-rw---- root system

m 5242883 00000000 --rw-r----- oracle asmadmin

m 1048580 00000000 --rw-r----- oracle asmadmin

m 1048581 00000000 --rw-r----- oracle asmadmin

m 5242886 00000000 --rw-r----- oracle asmadmin

m 1048583 0xd92489e0 --rw-r----- oracle asmadmin

m 1048584 0xd1a4a5d8 --rw-r----- grid dba

m 8388617 0x3f516768 --rw-r----- oracle asmadmin

m 759169034 0x21000148 --rw-rw---- oracle dba

[ZFXDESKDB2:oracle]:/oracle>ipcrm -m 5242886

[ZFXDESKDB2:oracle]:/oracle>ipcrm -m 5242883

[ZFXDESKDB2:oracle]:/oracle>ipcrm -m 1048583

[ZFXDESKDB2:oracle]:/oracle>sysresv

IPC Resources for ORACLE_SID "raclhr2" :

Shared Memory

ID KEY

No shared memory segments used

Oracle Instance not alive for sid "raclhr2"

[ZFXDESKDB2:oracle]:/oracle>ps -ef|grep ora_pmon_

oracle 17629238 1 0 18:57:42 - 0:09 ora_pmon_raclhr2

oracle 20250806 1 0 18:57:42 - 0:10 ora_pmon_oraESKDB2

oracle 23330844 21626964 0 17:44:46 pts/0 0:00 grep ora_pmon_

[ZFXDESKDB2:oracle]:/oracle>sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on Wed Jun 1 17:44:52 2016

Connected to an idle instance.

SYS@raclhr2> shutdown abort

ORACLE instance shut down.

SYS@raclhr2> exit

Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testing options

1.5 故障處理總結

①　ipcs和ipcrm應該學會使用

②　sysresv的使用可以檢視對應例項的共享記憶體段

③　文章中的所有MOS文章在小麥苗的雲盤中http://yunpan.cn/cdEQedhCs2kFz （提取碼：ed9b）

④　關於ipcs的使用cuug的老師也講過公開課，公開課的錄影檔案參考http://yunpan.cn/cdEQedhCs2kFz （提取碼：ed9b）

About Me

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● 本文作者：小麥苗，部分內容整理自網路，若有侵權請聯絡小麥苗刪除

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● 小麥苗的微店：https://weidian.com/s/793741433?wfr=c&ifr=shopdetail

● 小麥苗出版的資料庫類叢書：http://blog.itpub.net/26736162/viewspace-2142121/

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使用微信客戶端掃描下面的二維碼來關注小麥苗的微信公眾號（xiaomaimiaolhr）及QQ群（DBA寶典），學習最實用的資料庫技術。

小麥苗的微信公眾號小麥苗的DBA寶典QQ群2 《DBA筆試面寶典》讀者群小麥苗的微店

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