Re: Service names and dataguard
Date: Tue, 2 Jun 2015 10:26:15 -0400
Message-ID: <CAAaXtLDjHffYm168Gn_iK_H7_X2N_TueW9zCZO3fdr5b8MXuZg_at_mail.gmail.com>
I think Hans and Andrew are both correct.
First, a failover event should not (must not?) require a change to your connection definitions, wherever you happen to store them. Create a single TNS Alias that describes how to connect to the proper service on BOTH the primary and the standby database servers in a failover configuration. Applications attempting to connect will then connect to whichever server currently has the database open.
Next, if you are concerned about keeping your TNSNAMES.ORA current and consistent across multiple machines (especially clients, which DBAs rarely visit), the best thing to do is probably not to use TNSNAMES.ORA at all. Using LDAP to serve up your connection strings eliminates the problem of maintaining current/consistent definitions, however, you'll want to take care not to allow LDAP to become a single point of failure.
On Tue, Jun 2, 2015 at 9:56 AM, Andrew Kerber <andrew.kerber_at_gmail.com> wrote:
> You can use a trigger or srvctl to assign service names based on database
> role (primary or physical standby). You can then set up a single entry
> with 2 ip addresses (failover type entry) and it will connect to whichever
> node has the correct service name. Let me know if you need examples. For
> tnsnames, many companies will have a single file under version control for
> the entire company.
>
> Sent from my iPad
>
> On Jun 2, 2015, at 8:33 AM, Hans Forbrich <fuzzy.graybeard_at_gmail.com>
> wrote:
>
> On 02/06/2015 7:27 AM, Howard Latham wrote:
>
> Oracle 11.2 Linux RH E 4 Windows etc.
>
>
> When there are several interconnecting systems across windows and
> linux and a seemingly frequent need to switchover to standby
> databases on different boxes what is the simplest/ best way to make
> sure that tnsnames on every box is up to date or am I missing an
> important bit of technology?
>
> Oracle also supports replacing (or complementing) TNSNAMES.ora with LDAP.
>
>
> http://www.oracle.com/technetwork/database/enterprise-edition/migrating-guide-133059.pdf
>
> http://laurentschneider.com/wordpress/2006/10/migration-of-tnsnamesora-to-ldap-sun-java-system-directory-server.html
>
> /Hans
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Tue Jun 02 2015 - 16:26:15 CEST