Oracle Cloud (DBaaS) -> Oracle Cloud (DBaaS)

1. Introduction

The purpose of this Deployment guide is to demonstrate the way in which Dbvisit Standby 8.0 software can be used within the Oracle Database As A Service (DBaaS) space. In this guide, we focus on both the Primary and Standby databases hosted on DBaaS.  In another document, we focus on 'On-Premise Primary' to Standby hosts on 'DBaaS'. A link that document can be found here


2. Initial Setup and Configuration

2.1 Provisioning the Severs

Connect to Oracle Cloud Dashboard 

and Provision 2 Oracle Database Services as shown in the example below.


I generated a private and public set of key files using ssh-keygen from my local Linux machine.

I could then import this file into the cloud setup in both cases.

Confirm your setup and click "create".

From the Services Tab : 

Summary Details of the 2 Oracle Database Cloud Services are as follows :


Primary Server DetailsStandby Server Details

Name: dbvcloud01

OCPUs: 1

OS: OEL6

Memory: 7.5G

Storage: 150G

Version: 12.1.0.2

Edition: Standard Edition

Database: ORCL

Dbvisit Base: /usr/dbvisit

Standby Version: 8.0.12.19052

Name: dbvcloud02

OCPUs: 1

OS: OEL6

Memory: 7.5G

Storage: 150G

Version: 12.1.0.2

Edition: Standard Edition

Database: ORCL

Dbvisit Base: /usr/dbvisit

Standby Version: 8.0.12.19052

2.2 Preparing the Servers 

Connect to each of the cloud hosts with ssh, specifying the public key uploaded when creating the service, as user opc

From here execute sudo -s to switch to the root user and create the dbvisit directory in /usr.  Also vi the /etc/hosts file to reflect the IP address of the other node in each case.


Download the latest version of Dbvisit Standby for OEL6 and SCP to each of the cloud hosts.


In order for Dbvisit Standby to communicate between the 2 hosts, and to enable access to the GUI frontend, 3 ports need to be made available.  These are 7890 (Dbvnet), 7891 (Dbvagent) and 4433 (dbvserver: GUI). To do this, navigate to the summary page of each host and choose Access Rules from the menu. From here, click the "create rule" button and fill in the details.  The example below shows 1 rule per port range named dbvisit_ports.  It is also possible to create 1 rule per port and name them accordingly.



At this stage, these servers are ready for the next stage of installing the software.

3. Install, Configure and Run the Standby software

3.1 Installing and Configuring the Software

Unzip, Untar and the run the dbvisit installer following the instructions in the dbvisit installation guide as the user oracle. 

https://dbvisit.atlassian.net/wiki/display/DS8QSG/Dbvisit+Standby+8.0+User+Guide

On the node dbvcloud02, the dbvserver (option 5) was also installed.  Alternatively, a 3rd host could be configured for hosting the dbvserver.   Careful to ensure during the dbvnet configuration on each node that the correct hosts are specified for source and destination. The output from the installation on node2 is shown below for reference.

Once the software has been installed on both nodes.  Start the processes.

Additionally, on the standby node, start the dbvserver process

3.2 Start the GUI and Create the DDC

Start a web browser and navigate to the https://<dbvserver_host>:4433. In this case, the standby node.


Add an exception and proceed.

Enter the default username/password of admin/admin and proceed to the first screen, manage hosts.

Enter each of the hosts in turn, specifying the passphrase used at creation time.

Return to the Main Menu and then proceed on to creating the DDC

The creation of the DDC file is shown in the following steps.  

Firstly Create a directory for ARCHSOURCE and ARCHDEST parameters.  The former is only required in the event of a Graceful switchover when the Primary becomes a Standby database.  In this example, the same location is created on each server.

To create a DDC from the GUI. Choose the Manage Configurations Tab

Create a New Configuration.  Fill out the relevant entries (as shown in the example below) the click 'Submit'


3.3 Create the Standby Database


3.3.1 Creating the Standby with the GUI

Choose the Create Standby Database Tab from the Home Screen.

Select your configuration, New Database and edit the SPFILE parameters if required and then check there is enough space in the Source and Dest temp locations.

Click Submit.  The progress can be monitored from the resulting icon in the status bar.

3.3.2 Creating the Standby with the CLI

To Create the Standby database with the command line is shown below


3.4 Performing Basic Tasks

Some examples of basic tasks are outlined below.  Please refer to the online documentation for more details on each command.  

Using the GUI to Send logs to the Standby Site

3.4.1 Log Gap Report

Run a log gap report from the Primary Site

Also from the GUI


3.4.2 Log Transfer

Apply Logs at the Standby Site

3.4.3 Daemon Status

Start the Daemons for automatic send/apply from the GUI Database Actions Tab. 

The "lightning bolt" icon manages the daemon processes as shown below.


When started on both sites they Log gap managed automatically and if no natural log switches have occurred, the daemon will also signal a log switch to keep the standby LAG to the desired amount. More information regarding the daemon settings can be found here in Section 4


https://dbvisit.atlassian.net/wiki/display/DS8QSG/Dbvisit+Standby+Scheduling

3.4.4 Starting Standby Database in Readonly Mode

From the Database Actions Tab choose the Database Icon.  This allows the user to perform database actions on each node.

Before the Standby Database can be opened in readonly mode, there must be a log gap of 0 between the 2 systems.

Select the Standby Host, review the current status and Select Start READ ONLY.




Now, the status is Read Only for the standby database.

To switch back again.  Choose Restart



Now the Standby is back in recovery mode and the logs can be applied as normal.

3.5 Performing Graceful Switchover

The following screenshots show a Graceful Switchover from one Cloud Standby to the other using the GUI.  A first pre-requisite is to ensure that the daemons started earlier are not running whilst the switchover is in progress.

3.5.1 Check the Status of the Daemons

3.5.2 Graceful Switchover Icon

3.5.3 Check Log Gap is Zero and Click Submit

3.5.4 Locate the Task on the Task Bar


3.5.5 Monitor the Activity

3.5.6 Verify the New Roles within each of the Databases

Verify the new database roles within the database


3.6 Activate the Standby Database

It is possible to activate the Standby Database and make it become the new Primary.  This is also called failover to the standby database.

The assumption is that the original Primary site has been lost and needs to be rebuilt.  

From the Central Console/GUI Choose the "Activate Standby Database Command"

3.6.1 Choose the Activate Standby Database

3.6.2 Select the Configuration



3.6.3 Monitor the Task from The Task Bar



3.6.4 Verify the Status within the Database


3.6.5 Manage Configurations Tab Implications

Now the Manage Configurations Tab has the option to choose the hosts. This allows you to either accept the current configuration with the new Primary (old Standby site) or start again with the original Primary site and depends on the circumstances of the Activation.