Re: Urgent, 2 instances on same server, instance failover scenario..

From: DA Morgan <damorgan_at_psoug.org>
Date: Sat, 16 Jul 2005 18:25:45 -0700
Message-ID: <1121563551.57010@yasure>

hpuxrac wrote:
> DA Morgan wrote:
>

>>Mark D Powell wrote:
>>
>>
>>>You also have tansparent application failover where if node 1 drops
>>>processing of the process can be picked up and continued on another
>>>node.  But this has to be coded into your applicaion.
>>>
>>>HTH -- Mark D Powell --
>>
>>This may be a failure to understand what you have written but TAF
>>failover is done in Net SErvices and should not require any application
>>code changes.

>
>
> Mark's point is clear and to the point. Not many applications can take
> use of the limited capabilities provided in this situation.
>
> Some applications doing SELECT only processing can take some limited
> usage here.
>
> What don't you understand?

Source:
http://download-west.oracle.com/docs/cd/B14117_01/network.101/b10775/concepts.htm#sthref207

Quote:
"The Transparent Application Failover (TAF) feature is a runtime failover for high-availability environments, such as Oracle9i Real Application Clusters. TAF fails over and reestablishes application-to-service connections. It enables client applications to automatically reconnect to the database if the connection fails and, optionally, resume a SELECT statement that was in progress. The reconnection happens automatically from within the Oracle Call Interface (OCI) library."

Source:
http://download-west.oracle.com/docs/cd/B14117_01/network.101/b10775/advcfg.htm#sthref1281

Quote:
"TAF instructs Oracle Net to fail over a failed connection to a different listener. This enables the user to continue to work using the new connection as if the original connection had never failed.

TAF involves manual configuration of a net service name that includes the FAILOVER_MODE parameter included in the CONNECT_DATA section of the connect descriptor."

What Mark wrote was "... But this has to be coded into your applicaion" (see above) and what I wrote was that, unless I had misunderstood him, he was incorrect. For which part of this communication, between me and Mark do you require further clarification?

-- 
Daniel A. Morgan
http://www.psoug.org
damorgan_at_x.washington.edu
(replace x with u to respond)

Received on Sat Jul 16 2005 - 20:25:45 CDT