Please I need a solution in this my chalange. I have my database server (A) running in my office. I have a backup database sever (B) somewhere else. My challange is how to swicth to the backup server (B) when my main database sever (A) goes down. Also this swict has to be down in a small time frame.

That depends on how your servers are configured.

You might need to do all that manually.

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Debasis

Prolifik4life: Your challenge is rather vague. What happens when you have a schedule outage, i.e. take the system down to upgrade Oracle.? There should already exist a Backup/Restore Procedure as part of ones Business Continuity Plan and/or Disaster Recovery Plan. When you say the Backup server (B) is external to your office, does that mean in the same building, on the same network or external to the facility? Is server B used as a virtual server or mirror image of Server A? What do you do when you have to change the Oracle DB Password? Upgrades and password changes are scheduled outages that includes testing the Oracle DB once restored by testng all applications effected.

Hope this helps.

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