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Failover test in DR situation fails

LonelyDBAAug 15 2017 — edited Aug 16 2017

11.2.0.4

Data guard active-passive

Broker in use

Hi,

We have done a disaster-recovery scenario using data guard. It did not go as I expected, therefor I want your help.

We have two sites. A and B.

Site A runs two databases, primary instance and the secondary instance which is used for FAST_START FAILOVER. The observer runs on site A.

Site B runs a secondary instance.

We will re-deploy our application and start using the database at site B. (to simulate a complete crash on site A).

We cut the network traffic between site A and B.

Re-deployed our application.

I ran a "failover to db_on_site_b"

I got an error regarding FAST_START FAILOVER:

ORA-16829: lagging fast-start failover configuration

and a failover never occured.

As we where under a time limit I change the database to become a new primary using SQLPLUS. After the test I changed it back to a secondary.

No we are see the following errors:

On the primary on site A:

Error: ORA-16724: cannot resolve gap for one or more standby databases

On the old secondary on site B:

Error: ORA-16700: the standby database has diverged from the primary database

I tried to flashback instance on site B, but that did not help. I guess I have to recreate it.

But how to avoid this the next time?

How can I do a failover if I cant communicate with the primary on site A?

Regards

TheLonelyDBA

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Locked on Sep 13 2017
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