Infrastructure at your Service

Category Archives: Database Administration & Monitoring

David Barbarin

Sudden drop of the page life expectandy but don’t panic yet!

By | Database Administration & Monitoring, Development & Performance | No Comments

A couple of weeks ago, I had an interesting discussion with one of my customer about the page life expectancy (aka PLE). He asked me if monitoring the metric value is a best practice because he often noticed a big drop of the PLE under the recommended threshold during the night or sometimes during the business hours. In addition, he didn’t want to get false positive especially during the night when maintenance tasks are performed without…

 
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Nathan Courtine

SQL Server Database failed to generate a checkpoint

By | Database Administration & Monitoring | One Comment

Last time, I experienced a strange error when I tried to perform an integrity check or a simple checkpoint of a database: One or more recovery units belonging to database ‘mydatabase’ failed to generate a checkpoint. This is typically caused by lack of system resources such as disk or memory, or in some cases due to database corruption. Examine previous entries in the error log for more detailed information on this failure. The log scan…

 
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Pierre Sicot

Always-on Monitoring EM 13C

By | Database Administration & Monitoring | No Comments

As the Enterprise Manager Cloud 12c is configured for sending warnings and alerts if a target database is down, what’s happening if the Enterprise Manager Repository database crashes? With Enterprise Manager Cloud Control 12c, a quite good solution is available: after an easy configuration, the management agent is able to run script to notify database administrators there is a problem with the repository. But what happens if the OMS itself is down? Enterprise Manager 13c offers…

 
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Pierre Sicot

EM 13c target is fully broken !!

By | Database Administration & Monitoring | 2 Comments

At a client’ site I decided to install the Enterprise Manager Cloud Control 13c. I did not encountered any special problem :=) , then I installed an agent 13c on the development plattform and added targets as usual, but at this timeI discovered that half of my database targets in 11.2.0.3 version were in the following state : 2016-02-05 15:31:46,863 [2527:A154C6AD] INFO – Target: [oracle_database.TESTDBA] is fully broken: Dynamic Category property error (code=0x400) The gcagent.log showed…

 
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Franck Pachot

The taboo of ‘underscore parameters’

By | Database Administration & Monitoring | 6 Comments

By Franck Pachot . Oracle provides lots or parameters that can control the behavior of the software. The default values are probably the best ones most of the time. Hundreds of parameters are documented and we can set them to customize the Oracle software for our context because default values can’t fit all different database sizes, usage, workload, infrastructure, etc. And in addition to them there are those ‘underscore parameters’ or ‘hidden parameters’ or ‘undocumented…

 
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Mouhamadou Diaw

Dataguard Environment and Database Tempfiles

By | Database Administration & Monitoring | One Comment

Last day I found a curious message in the backup alert log in a dataguard environment. The message was related to an issue with the resync catalog and was something like RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03009: failure of resync command on default channel at 02/18/2016 17:48:42 ORA-00001: unique constraint (RMAN.TS_P2) violated After few researches, it seems that this error is due to a mismatch of tempfiles between Primary and Standby….

 
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David Barbarin

SQL Server AlwaysOn: when a listener becomes the cluster and vice versa

By | Database Administration & Monitoring, Database management | No Comments

Let’s talk about a funny story that concerns an interesting issue that I faced a couple of months ago at one of my customers. Initially, the problem concerned only the creation of an availability group listener but after deleting the related availability group, he noticed quickly that the deletion failed but even more strange, he noticed that the virtual network name related to the listener corresponded to the virtual computer object of the cluster itself….

 
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Vincent Matthey

GoldenGate 12.2 parameter file check

By | Database Administration & Monitoring | No Comments

Today I will talk about the new parameter file checks available to continue the series of blog posts about the new features of GoldenGate 12.2. There are three themes that I will present you: Checkprm utility Info param Getparaminfo Checkprm utility This utility can be used to validate a parameter file (.prm). It is located in the home of the GoldenGate installation. oracle@goldengate122:/u04/app/goldengate/product/12.2.0.0/DB1/ [DB1] ll | grep check -rwxrwxr-x 1 oracle oinstall 11216170 Nov 10…

 
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