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Connecting to a RAC (Real Application Cluster) using SQL*Net

Posted: Tue 24 May 2011 17:04
by fabnavigator
Hello,

Our IT department is migrating a number of our servers to a RAC configuration. After they do this, I am no longer able to connect to them using SQL*Net. I can still connect to the cluster with OCI using the TNS name.

Is there any way to connect to the cluster with SQL*Net?

Best regards,

Bill

Posted: Thu 26 May 2011 08:59
by AlexP
Hello,

I cannot reproduce the problem.
dbExpress driver for Oracle connects to Oracle RAC servers in the Direct mode successfully.
Please specify the exact version of your dbExpress driver for Oracle and send us your tnsnames.ora file and the Database value you are using.

Posted: Thu 26 May 2011 11:43
by fabnavigator
Hi,

Thank you for looking into this. I'm glad to hear that it works for you. Note: I replaced our domain name with "xxxxxxxxxxx".

I've tried both of these database strings:

DataBase=srd01v.xxxxxxxxxxx.com:1523:SN=vqaprod
DataBase=srd02v.xxxxxxxxxxx.com:1523:SN=vqaprod

I get: "Database Server Error: NET: Invalid Service Name"

Driver version: 4.90.0.25

Section of tnsnames.ora file:

VQA_PROD.WORLD =
(DESCRIPTION =
(FAILOVER = ON)
(LOAD_BALANCE = OFF)
(ADDRESS = (PROTOCOL = tcp)(HOST = srd02v.xxxxxxxxxxx.com)(PORT = 1523))
(ADDRESS = (PROTOCOL = tcp)(HOST = srd01v.xxxxxxxxxxx.com)(PORT = 1523))
(CONNECT_DATA =
(SERVICE_NAME = VQAPROD.xxxxxxxxxxx.COM)
)
)

Posted: Fri 27 May 2011 06:21
by AlexP
Hello,

To connect using Service Name, you should set the DataBase property in the following way:

Code: Select all

DataBase=srd02v.xxxxxxxxxxx.com:1523:SN=VQAPROD.xxxxxxxxxxx.COM
DataBase=srd01v.xxxxxxxxxxx.com:1523:SN=VQAPROD.xxxxxxxxxxx.COM

Posted: Sat 28 May 2011 12:22
by fabnavigator
Hi again,

I had tried that, and after a log wait, I get back "Database Server Error: ORA-12571".

Posted: Mon 30 May 2011 09:01
by AlexP
Hello,

Please try to connect to one of your Oracle servers using SID instead of Service Name. If the same error occurs in this case, please check records in the trace file (you should enable tracing).
Also please try to connect after disabling your antivirus program and firewall.

Posted: Tue 31 May 2011 19:20
by fabnavigator
Hi,

When I use the SID to connect to one of the two servers it works.

Posted: Wed 01 Jun 2011 08:27
by AlexP
Hello,

We cannot reproduce the problem on our RAC servers.
Try to connect using servers IP address instead of its name. If your server is accessible from the Internet, please tell us its exact address (we don't need login and password), and we will try to check this problem on your servers.

Posted: Wed 01 Jun 2011 11:51
by fabnavigator
Hi,

Sorry. These servers are not accessible from the Internet.

I have a question. Why do I need to include the server when connecting by Service Name? The server specified may not even be one that is up.

Also, I can connect by the Service Name from the "Oracle SQL Developer" application.

Posted: Wed 01 Jun 2011 12:42
by AlexP
Hello,

For the time being ODAC cannot switch between servers automatically in the Direct mode, that's why you have to specify the server to which you want to connect.
Please send your trace and log files to alexp*devart*com.

Posted: Wed 01 Jun 2011 12:51
by fabnavigator
Oh. If ODAC cannot switch between servers automatically in Direct mode, I don't need to be able to connect by Service Name.

The whole reason to use the Service Name was to get the automatic switching. If I'm on my own to know which server to connect to, I can just use the SID.

When, do you expect to have automatic switching available?

Posted: Wed 01 Jun 2011 13:31
by AlexP
Hello,

We are working on the implementation of this feature now. We plan to add it in one of the next versions.