Use SHARED SERVER over POLICY-MANAGED Database is supported?


Helping colleagues in OTN Forum I found a issue that have not been solved yet, but we must be aware of this issue before performing implementation.

When you are using policy-managed database Oracle Manage all instance automatically on demand without dba intervention. For the whole thing work well is mandatory use SCAN (IP and SCAN Listeners) and VIP (IP and Local Listeners) database use these resource to automatically register it's own services and that's way how the Oracle client will find a Oracle Instance.

When you Configure a SHARED SERVER on Policy-Managed Dababase one question arise:
SHARED SERVER don't use Parameter LOCAL_LISTENER to register database on Listener, but it use DISPATCHERS parameter.

DISPATCHERS parameter is NOT Like LOCAL_LISTENER parameter which automatically updated by Database Agent. Then you must set DISPATCHERS manually using VIP of current Node on each Instance. As explained in note How To Configure Shared Server Dispatchers For RAC Environment [ID 578524.1]. BUT this will work only if you have a ADMIN-MANAGED database because instance is fixed on that node.

Policy-managed database has not fixed a instance on specific node and also has not a specific INSTANCE_NAME, because INSTANCE_NAME can be changed automatically on demand or when you change configuration of your SERVER POOL.

The BIG QUESTION:
How configure DISPATCHERS parameter when database is POLICY-MANAGED ? Since DISPATCHERS can't be automatically configured dynamically, but the INSTANCE is dynamic and can be reloacated to any node on that server pool.

When I get the anwser I'll post here Oracle Solution. (If someone already has the answer please post here)

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What is slow RMAN or Media Management Library?

Backup execution time  is slow.. where is the problem?

When we perform backup using third party software and backup of database is slow, there always is some uncertain who is causing the slowness.

The Database Administrator (DBA) says: is Media Management Library (aka MML) and Backup Operator says: is RMAN.

To end this conflict I ​​will show how to identify where is the problem.

I'll use the term RMAN (like RMAN spend time), but actually means Database spend time. Because RMAN is only a client. So typically the database is slow and not RMAN Client is slow.

Note: I will not diagnose what is causing it, I will only  help you  identify whether the problem is, in  MML or RMAN.

Media Management

The Oracle Media Management Layer (MML) API lets third-party vendors build a media manager, software that works with RMAN and the vendor's hardware to allow backups to sequential media devices such as tape drives. A media manager handles loading, unloading, and labeling of sequential media such as tapes.

RMAN Interaction with a Media Manager

RMAN does not issue specific commands to load, label, or unload tapes. When backing up, RMAN gives the media manager a stream of bytes and associates a unique name with this stream. When RMAN must restore the backup, it asks the media manager to retrieve the byte stream. All details of how and where that stream is stored are handled entirely by the media manager. For example, the media manager labels and keeps track of the tape and names of files on each tape, and automatically loads and unloads tapes, or signals an operator to do so.

RMAN provides a list of files requiring backup or restore to the media manager, which in turn makes all decisions regarding how and when to move the data.

Before RMAN making a call to any of functions in the media management API, the server create a EVENT WAIT. So, These with  EVENT WAIT  is possible to get the number of  wait (in seconds or number) that the server has been waiting for this call to return.

So, we can calculate it and find out how much time RMAN spend waiting MML (e.g writing  or querying a backup piece filename) processing request and return to RMAN.

Complete list  EVENT of MML

Oracle 11.2 or above:

SELECT NAME
FROM   V$EVENT_NAME
WHERE  NAME LIKE '%MML%';
NAME
----------------------------------------
Backup: MML initialization
Backup: MML v1 open backup piece
Backup: MML v1 read backup piece
Backup: MML v1 write backup piece
Backup: MML v1 close backup piece
Backup: MML v1 query backup piece
Backup: MML v1 delete backup piece
Backup: MML create a backup piece
Backup: MML commit backup piece
Backup: MML command to channel
Backup: MML shutdown
Backup: MML obtain textual error
Backup: MML query backup piece
Backup: MML extended initialization
Backup: MML read backup piece
Backup: MML delete backup piece
Backup: MML restore backup piece
Backup: MML write backup piece
Backup: MML proxy initialize backup
Backup: MML proxy cancel
Backup: MML proxy commit backup piece
Backup: MML proxy session end
Backup: MML datafile proxy backup?
Backup: MML datafile proxy restore?
Backup: MML proxy initialize restore
Backup: MML proxy start data movement
Backup: MML data movement done?
Backup: MML proxy prepare to start
Backup: MML obtain a direct buffer
Backup: MML release a direct buffer
Backup: MML get base address
Backup: MML query for direct buffers

Previous version of Oracle Database 11.2 the Event name MML does not exists because it’s was changed on version 11.2 from %STB% to %MML%.

So, If you are using Oracle 11.1 or previous you can query V$EVENT_NAME where NAME like '%sbt%'.

SELECT NAME
FROM   V$EVENT_NAME
WHERE  NAME LIKE '%sbt%';

Backup: sbtinit
Backup: ssbtopen
Backup: ssbtread
Backup: ssbtwrite
Backup: ssbtbackup
.
.
.

So, lets start...
Oracle store statistics (cumulative, since database was started) of these wait on v$system_event. I always use GV$ because is very common we admin RAC env on this days.

Before start backup I'll take a snapshot intial of gv$system_event...by creating a table RMAN_MML_EVENT_T1.

Click on icon "View Source" to see formated text.

CREATE TABLE  RMAN_MML_EVENT_T1 AS
SELECT inst_id,
  event,
  TOTAL_WAITS,
  TOTAL_TIMEOUTS,
  TIME_WAITED,
  AVERAGE_WAIT,
  TIME_WAITED_MICRO,
  sysdate as SNAPSHOT_TIME
FROM gv$system_event
WHERE event LIKE 'Backup%';

SQL> select * from RMAN_MML_EVENT_T1;

   INST_ID EVENT                                   TOTAL_WAITS TOTAL_TIMEOUTS TIME_WAITED AVERAGE_WAIT TIME_WAITED_MICRO SNAPSHOT_TIME
---------- --------------------------------------- ----------- -------------- ----------- ------------ ----------------- -----------------
         1 Backup: MML initialization                      371              0       54365       146.54         543651136 08-08-12 17:11:05
         1 Backup: MML create a backup piece               450              0        4827        10.73          48270960 08-08-12 17:11:05
         1 Backup: MML commit backup piece                 450              0        7417        16.48          74172281 08-08-12 17:11:05
         1 Backup: MML shutdown                            371              0          47          .13            469267 08-08-12 17:11:05
         1 Backup: MML query backup piece                  894              0       11222        12.55         112222166 08-08-12 17:11:05
         1 Backup: MML extended initialization             371              0           0            0              3655 08-08-12 17:11:05
         1 Backup: MML delete backup piece                 444              0        5348        12.05          53480530 08-08-12 17:11:05
         1 Backup: MML write backup piece              1378078              0     3053683         2.22        3.0537E+10 08-08-12 17:11:05

8 rows selected.

I started backup using RMAN and MML (Tivoli Storage Manager). When backup finished you can query V$RMAN_BACKUP_JOB_DETAILS to get accurate time of backup

SELECT START_TIME,
  END_TIME,
  ROUND(INPUT_BYTES  /1024/1024/1024,2) IMPUT_GBYTES ,
  ROUND(OUTPUT_BYTES /1024/1024/1024,2) OUTPUT_GBYTES,
  INPUT_TYPE,
  ELAPSED_SECONDS
FROM V$RMAN_BACKUP_JOB_DETAILS
WHERE TRUNC(START_TIME) = TRUNC(SYSDATE)
AND INPUT_TYPE LIKE 'DB%';

START_TIME        END_TIME          IMPUT_GBYTES OUTPUT_GBYTES INPUT_TYPE    ELAPSED_SECONDS
----------------- ----------------- ------------ ------------- ------------- ---------------
08-08-12 17:23:44 08-08-12 17:26:38        12.85         10.06 DB FULL                   174

In my case the backup full take 174 seconds to backup read 12.85GB and Write on MML 10.06GB of data

So, after backup finish I take the 2nd snapshot by creating the table RMAN_SNAPSHOT_T2.


CREATE TABLE  RMAN_SNAPSHOT_T2 AS
SELECT inst_id,
  event,
  TOTAL_WAITS,
  TOTAL_TIMEOUTS,
  TIME_WAITED,
  AVERAGE_WAIT,
  TIME_WAITED_MICRO,
  sysdate as SNAPSHOT_TIME
FROM gv$system_event
WHERE event LIKE 'Backup%';

SQL> select * from RMAN_MML_EVENT_T2;

   INST_ID EVENT                                   TOTAL_WAITS TOTAL_TIMEOUTS TIME_WAITED AVERAGE_WAIT TIME_WAITED_MICRO SNAPSHOT_TIME
---------- --------------------------------------- ----------- -------------- ----------- ------------ ----------------- -----------------
         1 Backup: MML initialization                      373              0       54665       146.56         546652333 08-08-12 17:27:45
         1 Backup: MML create a backup piece               454              0        4860        10.71          48604759 08-08-12 17:27:45
         1 Backup: MML commit backup piece                 454              0        7482        16.48          74820999 08-08-12 17:27:45
         1 Backup: MML shutdown                            373              0          47          .13            471590 08-08-12 17:27:45
         1 Backup: MML query backup piece                  900              0       11281        12.53         112808077 08-08-12 17:27:45
         1 Backup: MML extended initialization             373              0           0            0              3665 08-08-12 17:27:45
         1 Backup: MML delete backup piece                 446              0        5373        12.05          53727006 08-08-12 17:27:45
         1 Backup: MML write backup piece              1419274              0     3067298         2.16        3.0673E+10 08-08-12 17:27:45

8 rows selected.

Now I can calculate the values from RMAN_MML_EVENT_T2 minus RMAN_MML_EVENT_T1 to get the real time spend on MML.
Note:
EVENT: Name of the wait event
TOTAL_WAITS: Total number of waits for the event
TOTAL_TIMEOUTS: Total number of timeouts for the event
TIME_WAITED: Total amount of time waited for the event (in hundredths of a second)
AVERAGE_WAIT: Average amount of time waited for the event (in hundredths of a second)
TIME_WAITED_MICRO: Total amount of time waited for the event (in microseconds)

SELECT t1.inst_id,
  t1.event,
  t2.total_waits       - t1.total_waits total_waits,
  t2.total_timeouts    -t1.total_timeouts total_timeouts,
  t2.time_waited       - t1.time_waited time_waited,
  t2.time_waited_micro - t1.time_waited_micro time_waited_micro
FROM RMAN_MML_EVENT_T1 T1,
  RMAN_MML_EVENT_T2 T2
WHERE t1.inst_id = t2.inst_id
AND t1.event     = t2.event;

   INST_ID EVENT                                   TOTAL_WAITS TOTAL_TIMEOUTS TIME_WAITED TIME_WAITED_MICRO
---------- --------------------------------------- ----------- -------------- ----------- -----------------
         1 Backup: MML initialization                        2              0         300           3001197
         1 Backup: MML create a backup piece                 4              0          33            333799
         1 Backup: MML commit backup piece                   4              0          65            648718
         1 Backup: MML shutdown                              2              0           0              2323
         1 Backup: MML query backup piece                    6              0          59            585911
         1 Backup: MML extended initialization               2              0           0                10
         1 Backup: MML delete backup piece                   2              0          25            246476
         1 Backup: MML write backup piece                41196              0       13615         136141912

8 rows selected.

As I can see above the MML spend more time writing backup piece.

So, I'll sum the time to get total time spend on MML.

SELECT SUM (total_waits) total_waits,
  SUM(total_timeouts) total_timeouts ,
  SUM (time_waited)/100 time_waited_in_second,
  SUM (time_waited_micro) time_waited_micro
FROM
  (SELECT t1.inst_id,
    t1.event,
    t2.total_waits       - t1.total_waits total_waits,
    t2.total_timeouts    -t1.total_timeouts total_timeouts,
    t2.time_waited       - t1.time_waited time_waited,
    t2.time_waited_micro - t1.time_waited_micro time_waited_micro
  FROM RMAN_MML_EVENT_T1 T1,
    RMAN_MML_EVENT_T2 T2
  WHERE t1.inst_id = t2.inst_id
  AND t1.event     = t2.event
  )

TOTAL_WAITS TOTAL_TIMEOUTS TIME_WAITED_IN_SECOND TIME_WAITED_MICRO
----------- -------------- --------------------- -----------------
      41218              0                140.97         140960346

Calculating time total of backup window, time spend on MML and time spend of RMAN.

Note: TIME_SPEND_BY_RMAN = (ELAPSED_SECOND_BACKUP-TIME_SPEND_BY_MML_SECOND)

ELAPSED_SECONDS_BACKUP          TIME_SPEND_BY_MML_SECOND       TIME_SPEND_BY_RMAN_SECOND
------------------------------ ------------------------------ -------------------
174                             140.97                         33.03

Summarizing:
Total time of backup : 174
Time spend by MML: 141
Time spend by RMAN : 33

If this backup is slow is because MML take (141*100/174) 81% of time spend of backup window.

Additional info:
As my backup was done over Lan:
(10.06GB * 1024 = 10301MB)
10301MB / 144 = 71Mbytes/second

As I'm using network interface of 1 Gbit I can consider a normal throughput.

Also you can monitoring in real time where is wait.

Just execute this script above:

Note : if you are using previous version of 11.2 change %MML% to %sbt%.

vi monitoring_mml.sh
sqlplus -s sys/<password>@<db_name> as sysdba<<EOF
set echo off
COLUMN EVENT FORMAT a17
COLUMN SECONDS_IN_WAIT FORMAT 999
COLUMN STATE FORMAT a15
COLUMN CLIENT_INFO FORMAT a30
set linesize 200

select to_char(sysdate,'dd-mm-yyyy hh24:mi:ss') actual_date from dual;

SELECT p.SPID, sw.EVENT, sw.SECONDS_IN_WAIT AS SEC_WAIT, 
       sw.STATE, CLIENT_INFO
FROM   gV\$SESSION_WAIT sw, gv\$SESSION s, gV\$PROCESS p
WHERE  sw.EVENT LIKE '%MML%'
AND    s.SID=sw.SID
AND    s.PADDR=p.ADDR;
EOF
exit

Using shell execute the command above, and you will see in real time the wait on MML.

while true
do
sh monitoring_mml.sh
sleep 1
done

.

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Oracle Real Application Clusters on IBM AIX – Best practices in memory tuning and configuring for system stability

Customers who experience Oracle Real Application Clusters (RAC) node evictions due to  excessive AIX kernel paging should carefully review and implement these recommended best practices. Testing and experience have found that memory over commitments may
cause scheduling delays for Oracle’s ‘oprocd’ process in Oracle RAC versions prior to 11.2 which may result in node evictions. Implementing all of these recommendations will reduce scheduling delays and corresponding oprocd initiated evictions for Oracle RAC versions prior to 11.2. For Oracle RAC versions 11.2 and later, implementing all of these recommendations will ensure optimal performance and scalability

 

http://www.oracle.com/technetwork/products/clusterware/overview/rac-aix-system-stability-131022.pdf

If link above is broke see below  click below:

rac-aix-system-stability-131022

Enjoy…

 


Oracle RDBMS Server 11gR2 Pre-Install RPM

Oracle RDBMS Server 11gR2 Pre-Install RPM for Oracle Linux 6 has been released

By Lenz Grimmer

 Now that the certification of the Oracle Database 11g R2 with Oracle Linux 6 and the Unbreakable Enterprise Kernel has been announced, we are glad to announce the availability of oracle-rdbms-server-11gR2-preinstall, the Oracle RDBMS Server 11gR2 Pre-install RPM package (formerly known as oracle-validated). Designed specifically for Oracle Linux 6, this RPM aids in the installation of the Oracle Database.

In order to install the Oracle Database 11g R2 on Oracle Linux 6, your system needs to meet a few prerequisites, as outlined in the Linux Installation Guides. Using the Oracle RDBMS Server 11gR2 Pre-install RPM, you can complete most of the pre-installation configuration tasks. which is now available from the Unbreakable Linux Network, or via the Oracle public yum repository.

https://blogs.oracle.com/linux/entry/oracle_rdbms_server_11gr2_pre

Enjoy


Local/SCAN Listener – Enhancing Security (Oracle Security Alert)

Recently we discovered  a possible vulnerability on SCAN Listener,  so we opened   SR  and Oracle give us a solution.

I recommend all apply this security. “As far as I know only the availability can be affected, none concern about data integrity” .

Thread: How prevent REMOTE LISTENER register on SCAN LISTENER
https://forums.oracle.com/forums/thread.jspa?threadID=2369472

Oracle Security Alert for CVE-2012-1675

This security alert addresses the security issue CVE-2012-1675, a vulnerability in the TNS listener which has been recently disclosed as “TNS Listener Poison Attack” affecting the Oracle Database Server. This vulnerability may be remotely exploitable without authentication, i.e. it may be exploited over a network without the need for a username and password. A remote user can exploit this vulnerability to impact the confidentiality, integrity and availability of systems that do not have recommended solution applied.

Affected Products and Versions
Oracle Database 11g Release 2, versions 11.2.0.2, 11.2.0.3
Oracle Database 11g Release 1, version 11.1.0.7
Oracle Database 10g Release 2, versions 10.2.0.3, 10.2.0.4, 10.2.0.5

Solution

Recommendations for protecting against this vulnerability can be found at:

Please note that Oracle has added Oracle Advanced Security SSL/TLS to the Oracle Database Standard Edition license when used with the Real Application Clusters and Oracle has added Oracle Advanced Security SSL/TLS to the Enterprise Edition Real Application Clusters (Oracle RAC) and RAC One Node options so that the directions provided in the Support Notes referenced above can be applied by all Oracle customers without additional cost.

Note: Please refer to the Oracle licensing documentation available on Oracle.com regarding licensing changes that allow Oracle Advanced Security SSL/TLS to be used with Oracle SE Oracle Real Application Clusters and Oracle Enterprise Edition Real Application Customers (Oracle RAC) and Oracle RAC OneNode Options.

Due to the threat posed by a successful attack, Oracle strongly recommends that customers apply this Security Alert solution as soon as possible.

http://www.oracle.com/technetwork/topics/security/alert-cve-2012-1675-1608180.html

.


News: Now is Supported BACKUPSET/ARCHIVELOG/DUMPSET files on ACFS 11.2.0.3

Starting with Oracle Automatic Storage Management 11g Release 2 (11.2.0.3), Oracle ACFS supports RMAN backups (BACKUPSET file type), archive logs (ARCHIVELOG file type), and Data Pump dumpsets (DUMPSET file type). Note that Oracle ACFS snapshots are not supported with these files.

 

ASM best practices we recommend to have two ASM disk groups:

DATAOH Diskgroup contains:
  • Database files (Database files must be stored directly in ASM and not on ACFS)
  • Oracle Clusterware files (OCR/Vote files)
  • ASM Spfile
  • ADVM volumes/ACFS filesystems for database related data or general-purpose use

 

FRA Diskgroup

This disk group will be used to store database recovery related files; such as archived log files, RMAN backups, and Flashback logs

  • Datapump dumpsets , RMAN backup files, etc. This was supported in ACFS 11.2.0.3 and above; however, ACFS does not currently support snapshots of filesystems housing  these files.
  • Additionally, database ORACLE_HOME backups (possibly zipped backups), can stored in a filesystem carved from the FRA disk group
ACFS Technical Overview and Deployment Guide [ID 948187.1]

http://docs.oracle.com/cd/E11882_01/server.112/e18951/asmfilesystem.htm#CACJFGCD

 

Enjoy…

 

 


RACcheck – RAC Configuration Audit Tool

RACcheck is a tool developed by the RAC Assurance development team for use by customers to automate the assessment of RAC systems for known configuration problems and best practices.

RACcheck is a RAC Configuration Audit tool  designed to audit various important configuration settings within a Real Application Clusters (RAC), Oracle Clusterware (CRS), Automatic Storage Management (ASM) and Grid Infrastructure environment. The tool audits configuration settings within the following categories:

  1. OS kernel parameters
  2. OS packages
  3. Many other OS configuration settings important to RAC.
  4. CRS/Grid Infrastructure
  5. RDBMS
  6. ASM
  7. Database parameters
  8. Many other database configuration settings important to RAC.

Features
1. RACcheck is NON-INTRUSIVE and does not change anything in the environment, except as detailed below:

– SSH user equivalence for the RDBMS software owner is assumed to be configured among all the database servers being audited in order for it to execute commands on the remote database server nodes. If the tool determines that this user equivalence is not established it will offer to set it up either temporarily or permanently at the option of the user. If the user chooses to set up SSH user equivalence temporarily then the script will do so for the duration of the execution of the tool but then it will return the system to the state in which it found SSH user equivalence originally. For those wishing to configure SSH user equivalence outside the tool (if not already configured), consult My Oracle Support Note: 372795.1.

– RACcheck creates a number of small output files into which the data necessary to perform the assessment is collected

– RACcheck creates and executes some scripts dynamically in order to accomplish some of the data collection

– RACcheck cleans up after itself any temporary files that are created and not needed as part of the collection.

2. RACcheck interrogates the system to determine the status of the Oracle stack components (ie., Grid Infrastructure, RDBMS, RAC, etc) and whether they are installed and/or running. Depending upon the status of each component, the tool runs the appropriate collections and audit checks. If due to local environmental configuration the tool is unable to properly determine the needed environmental information please refer to the TROUBLESHOOTING section.

3. Watchdog daemon – RACcheck automatically runs a daemon in the background to monitor command execution progress. If, for any reason, one of the commands run by the tool should hang or take longer than anticipated, the monitor daemon kills the hung command after a configurable timeout so that main tool execution can progress. If that happens then the collection or command that was hung is skipped and a notation is made in the log. If the default timeout is too short please see the TROUBLESHOOTING section regarding adjustment of the RAT_TIMEOUT, and RAT_ROOT_TIMEOUT parameters.

4. If RACcheck’s driver files are older than 90 days, the driver files are considered to be “stale” and the script will notify the user of a stale driver file. A new version of the tool and its driver files (kit) must be obtained from MOS Note 1268927.1.

5. When the RACcheck completes the collection and analysis it produces two reports, summary and detailed. A output .zip file is also produced by RACcheck. This output .zip file can be provided to Oracle Support for further analysis if an SR needs to be logged. The detailed report will contain Benefit/Impact, Risk and Action/Repair information. In many cases it will also reference publicly available documents with additional information about the problem and how to resolve it.

6. The results of the audit checks can be optionally uploaded into database tables for reporting purposes. See below for more details on this subject.

7. In some cases customers may want to stage RACcheck on a shared filesystem so that it can be accessed from various systems but be maintained in a single location rather than being copied to each cluster on which it may be used. The default behavior of the tool is to create a subdirectory and its output files in the location where the tool is staged. If that staging area is a read only filesystem or if the user for any reason would like the output to be created elsewhere then there is an environment variable which can be used for that purpose. The RAT_OUTPUT parameter can be set to any valid writable location and the output will be created there.

Applies to:
Oracle Server – Enterprise Edition – Version: 10.2.0.1 to 11.2.0.2 – Release: 10.2 to 11.2

  • Linux x86
  • IBM AIX on POWER Systems (64-bit)
  • Oracle Solaris on SPARC (64-bit)
  • Linux x86-64

To download RAC Check tool use this note on MoS:
RACcheck – RAC Configuration Audit Tool [ID 1268927.1]

Example of report output:

raccheck Report

Enjoy