Manage Your Existing Data Guards with Enterprise Manager Cloud Control

It’s very easy to build a Data Guard using Enterprise Manager Cloud Control (I’ll surely blog about it soon) and it’s also possible to manage your existing Data Guards with Enterprise Manager Cloud Control. Enterprise Manager will automatically detect Data Guard configuration of the target databases but if you need to administer your Data Guard with Enterprise Manager, your database should be configured by Data Guard broker. One of the good thing is, Enterprise Manager Cloud Control also help you to set up Data Guard broker for existing Data Guards with a few clicks.

First of all, you should deploy Enterprise Manager agents to the both primary and standby servers. Then you should add these databases (including standby database) to Enterprise Manager. While adding standby database, Enterprise Manager will complain that it will not be able to monitor it because standby database is read-only (11g Active Data Guard) or in mounted mode. Ignore the warning and add the standby database without monitoring. If you do not have a DNS in your network to resolve host names, make sure that you add hostnames and IP address to /etc/hosts file of primary and standby servers. So you should be able to resolve the hostname of standby server on primary server, and resolve the hostname of standby server on primary server.

If it is not an Active Data Guard, Enterprise Manager agent will not be able to connect your standby database and you’ll see your standby database is “down”. That’s not a problem, ignore the status of standby database for now.

When both primary and standby is added to Enterprise Manager system, go to the main page of the primary database and click “availability” and then click “add standby database”.

Select “manage an existing standby database with Data Guard broker”, and go to next step.

Enterprise Manager will show you the possible standby databases. Select the correct one, and click “next”.

Enterprise Manager will show you the configured “standby destinations”, select the one which belongs to your standby, so Enterprise manager will “overwrite” it and will not duplicate the standby destinations. On next stage, review the settings and click “finish” to re-configure data guard. While re-configuring data guard, Enterprise Manager will use your current Data Guard settings.

This process can not be cancelled, just wait until it ends.

Check the status of your data guard. As you see, there’s a “ORA-16803” error because my databases are Oracle 9i and Data Guard Broker tries to query a view which doesn’t exist in Oracle 9i (I couldn’t debug it yet). If you see another error, you may want to “verify configuration” (its link is in the additional administration section), but be careful: While verifying configuration, Enterprise Manager will suggest you some settings and if you just accept these settings without reading, your data guard can be misconfigured.

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AWS Big Data Specialist. Oracle Certified Professional (OCP) for EBS R12, Oracle 10g and 11g. Co-author of "Expert Oracle Enterprise Manager 12c" book published by Apress. Awarded as Oracle ACE (in 2011) and Oracle ACE Director (in 2016) for the continuous contributions to the Oracle users community. Founding member, and vice president of Turkish Oracle User Group (TROUG). Presented at various international conferences including Oracle Open World.


  1. Christian Trieb

    Hello Gökhan,

    you wrote: “While adding standby database, Enterprise Manager will complain that it will not be able to monitor it because standby database is read-only”

    How can I adding the existing Standby DB with OEM 12c?

    Best regards


    • Gokhan Atil

      Hi Christian, this post exactly explains how to add existing standby DB. It will not re-create the standby, just re-configures its settings.

  2. Neeraj Vasudeva


    Small question.. I created a Oracle 12c dataguard and i also created config. using dgmgrl and then i added primary and standby in em12c. I dont know if it’s standard behavious but my physical standby pluggable db shows as down in em12c. Is this an expected behavior ?

    Note : I have configured DG and not ADG. Also for physical standby in EM12c, i have supplied sys account privs instead of using dbsnmp account.




  3. Lancerique

    After promoting standby database, it not shown in the list of “manage an existing standby database with Data Guard broker”. Is there any specific property we need to set?

    • you might have to wait for a couple of minutes. Also Your agent might cause problems and you can try to submit a ./emctl stop agent;./emctl clearstate agent;./emctl start agent;./emctl upload agent. If still the problem continue, then you have to investigate some logs

  4. Funny thing – sometimes Enterprise Manager 13c is giving a severity of “warning” for the standby database as this is i MOUNTED state. In a dataguard environement this state is normal and shouldn’t be reported like this in incident manager. This happens a little bit random and I haven’t figured why… anybody else seeing this behaviour ?

  5. Sultan Abdul Hameed II

    Thanks. Very helpful.


    If you already have DataGuard setup, then EM automatically recognizes the standby database. But you must log in as sysdba for EM for dataguard to work with EM. 🙂

  6. abdul taher

    Hi Atil,

    we are using 13C OEM and not using Data Guard Broker, Can i refer this document for adding existing standby database.

    Best Regard’s
    Abdul Taher

    • Gokhan Atil

      Yes you can but as I remember it enables data guard broker at the end.

  7. Ed Charter

    Hi I need to upgrade OEM agents from 13.3 to 13.4 in a dataguard environment. Please let me know how this can be done by not breaking the dataguard broker.


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