EM won’t start after upgrade

After upgrading a database from to, I was unable to start the Oracle Enterprise Manager. Whenever I tried to do so, the log showed that it failed to start Database Control. Even when I deconfigured the Enterprise Manager, deleted the repository and started from scratch, I still ran into the same problem. In this post, I will describe the symptoms I encountered and also provide a solution.

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New Instance or New Schema?

So when it comes to deploying a new application there is always the question if you should create a new instance on the database server or use the existing instance and just add a new schema? These both are valid options, but lets have a look at both options.

Lets assume you already have one instance running one application, now you need to provide a new database to a user. So depending on the application, you have the choice of creating a new instance for this specific new application or to use an existing database instance and just creating a new schema.

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Our solution to ORA-12571

After a database update from to on Windows Server 2003, we encountered the ORA-12571 error when starting the Application Server. In the log files, the error showed up as an SQLException:

java.sql.SQLException: Io exception: Connection reset by peer: socket write error

I then used TNSPing to validate the connection to the database and I basically received this result:


This means that there is a problem with the TNS Listener. I checked the listener log ($ORACLE_HOME\network\log\listener_name.log) for errors and saw this:

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Apply Patchset to Oracle 10gR2

One of the regularly recurring tasks is to apply a Patchset to a database. This post contains the basic steps required to apply Patchset to an unpatched Oracle 10g Database ( I am using this post mainly for my own reference, so please do not expect an extensive step-by-step guide. Note that you need Oracle Support (formerly Metalink) to access and download the patches.

Before we begin, I must state that I provide these instructions based on my experiences with database upgrades and these are by no means complete. When applying a Patchset, always refer to the patch_note.html provided in the installation media. This means you can use my steps only as a coarse guide. These steps can also be used to create your own “Upgrade Checklist”.

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Hello world

My name is Simon Krenger, I am a Technical Account Manager (TAM) at Red Hat. I advise our customers in using Kubernetes, Containers, Linux and Open Source.


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