Re: i canīt see databases folder in the enterprise manager console tree.

From: Howard J. Rogers <hjr_at_dizwell.com>
Date: Sun, 12 Sep 2004 07:14:48 +1000
Message-Id: <41436ace$0$15470$afc38c87@news.optusnet.com.au>

Angel López wrote:

> Iīve a new oracle user.
> I have installed oracle 8i enterprise edition on a XP O.S pc.
> I have configured the oracle enterprise manager, but when i start the
> oracle enterprise manager console, and
> discover nodes, my node "PC1" is discovered, but i canīt see the
> databases folder.
> I cant see my database.
> I only can see into my node pc1, the web severs folder.
>
> please help me :-)
>
> thanks you
>
> Angel López

What Sybrand says about this being a non-certified configuration is true, so that is indeed a concern.

But I bet your specific issue is that your Listener has only been configured with dynamic instance configuration, and not with a static SID_LIST section in the init.ora.

The story can be a long-ish one to tell, so here goes. Instances automatically register themselves with instances in 8i and above. At startup, and at regular intervals thereafter, PMON announces the existence of the instance to the Listener. The Listener then knows it can handle connection requests received for that instance from clients.

The Listener.ora for a listener configured in this way reads something like this:

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =

      (ADDRESS_LIST = 
         (ADDRESS = (PROTOCOL=TCP)(HOST=mozart)(PORT=1521))
      )
     )

   )

So, that's all you need to get PMON talking to the Listener, and clients able to connect to the instance.

The trouble starts when you want to run Enterprise Manager. Enterprise Manager is only aware of instances which are known to the *Intelligent Agent*, not the Listener. And the Intelligent Agent isn't very intelligent at all, and itself only knows about instances which are explicitly declared to exist in a different section of the listener.ora -the SID_LIST section.

My full listener.ora thus reads as follows:

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =

      (ADDRESS_LIST = 
         (ADDRESS = (PROTOCOL=TCP)(HOST=mozart)(PORT=1521))
      )
     )

   )

SID_LIST_LISTENER =
   (SID_LIST

     (SID_DESC = 
        (GLOBAL_DBNAME = LX10.DIZWELL.COM)
        (ORACLE_HOME = /oracle/10g)
        (SID_NAME = LX10)
     )

    )

The first bit is technically all I need to connect to the instance. But the second bit is there these days just to let the Intelligent Agent know what it ought to be aware of. And once the Agent is aware of it, Enterprise Manager will be. (I say 'these days' because before we had dynamic, automatic instance registration, the SID_LIST section was the only way of the listener itself finding out what instances it was handling connnections for. It therefore used to be compulsory).

I don't know for sure whether that's actually your issue, but it's usually so. You'll need either to manually edit your listener.ora in ORACLE_HOME\network\admin, and then re-start both the listener and the intelligent agent services; or, you can use the Net Manager tool (NOT the network configuration assistant) to add 'Database Services' to a listener -which is the posh way of saying 'bung a SID_LIST in the listener.ora'. Even there, though, you will need to restart the listener and the intelligent agent before anything takes effect.

Also: instead of running Enterprise Manager and refreshing your nodes to see whether the alteration to the listener.ora has achieved anything, try instead just looking at the contents of the ORACLE_HOME\network\agent and the services.ora file found there. The contents of this file determines what services (ie, instances) the Agent is aware of. So if your instance can be found anywhere in this file after you've stopped and re-started the Agent, you know with certainty that Enterprise Manager will be able to find it after a node refresh.

But after all that, I'd still agree with Sybrand that you are using a very old database version on an unsupported platform. Given that you can download 9i and 10g from http://technet.oracle.com for free, I'd suggest upgrading yourself to one of those more modern versions -both of which work fine on Windows XP, and both of which have a future beyond this December (when official support for 8i comes to an end).

Regards
HJR Received on Sat Sep 11 2004 - 16:14:48 CDT