Installation Prerequisites

When installing Dbvisit Standby on an environment using ASM for database storage, Oracle Grid Infrastructure version 11.1 and higher is recommended.

Using version 10.2 for ASM storage is not recommended and will limit the functionality of Dbvisit Standby - Graceful Switchover will not be possible.


Starting the instance using "srvctl start instance -d DBTEST -i DBTEST1" changes the group of the oracle binary. (Doc ID 1508027.1)

This is an expected behavior. The group setting of the oracle binary is changed to the group setting of asm like asmadmin because the role separation of asm and database is introduced in 11.2.  As a result, in order to allow the database to access the asm disks, the group setting of the oracle binary needs to be changed to the group setting of asm.

The $GI_HOME/bin/setasmgid which is the executable that changes the group of the oracle binary in the database home(s).

.
1. When you install GI, you need to choose the owner and the group that owns
the disks used for ASM. This is the ASM_GRP, which you specified when you
installed, for example, as dba.
.
2. When the agent starts, this changes the group of the DB oracle executable
to be the same as the ASM_GRP from the GI home. This is made to give access
to the disks used for ASM.
.
If the RDBMS was installed with a different group (for example, oinstall), then the group changes to the ASM_GRP (i.e. from oinstall to asmadmin in the example case).
.
This change does not have any adverse affect if the DB and GI homes are owned by the same user because the same user is the owner for the ASM disks.

 

Before installing Dbvisit Standby please ensure that the following prerequisites are met:

 

Dbvisit Standby software must be installed with the same account that is running the Oracle Database software.

Example on most UNIX systems the operating system user used to install and run the Oracle database software is "oracle" .

You must install Dbvisit Standby as this user. Keep in mind that Dbvisit Standby needs to stop/start the databases during Graceful Switchover and using a different user can have side effects.

 

 

Task

Description

Primary Server:

Oracle Software

When looking at installing the Dbvisit Standby product, you need to make sure that the required supported Oracle Database software is already installed and configured.

For Oracle 12c on Windows you will need to use Dbvisit Standby version 7.0.22 or higher

No outage is required for the installation of Dbvisit Standby.

On Linux a few key points to take into account:

  • The location of the Oracle software is called the ORACLE_HOME.  In the Dbvisit Standby configuration this variable is also called ORACLE_HOME.
  • It is recommended that the database be listed in the /etc/oratab file
  • Dbvisit Standby should be installed as the same user that was used to install the Oracle Database Software
  • If role separation is used, where the Grid Infrastructure software is installed and owned by the “grid” user, and the Oracle Database software is owned by the “oracle” use, Dbvisit Standby should be installed as the “oracle” user

 

Standby Server:

Oracle Software

When looking at installing the Dbvisit Standby on the standby server, you need to make sure that the required supported Oracle Database software is already installed and configured.  Dbvisit Standby can be used to create the standby database for you once it is configured.  But if you already have a standby database in place, you can configure Dbvisit Standby to update and maintain the standby database going forward.

On Linux a few key points to take into account:

  • The location of the Oracle software is called the ORACLE_HOME.  In the Dbvisit Standby configuration this variable is called ORACLE_HOME_DR.
  • It is recommended that the database be listed in the /etc/oratab file
  • Dbvisit Standby should be installed as the same user that was used to install the Oracle Database Software
  • If you are planning on using ASM storage for the standby database and you are using role separation (meaning Oracle Database software is installed as the "oracle" Unix account and the Grid Infrastructure software is installed as the "grid" Unix account) you will need to make sure that the Oracle executable in the Oracle Database software home has the correct permissions. If you do not have the correct permissions you will potentially get ORA-15025 errors, as you will not be able to see the ASM storage when creating a new database manually. For more details see this the Oracle Support note: 1084186.1.  The steps below can be followed to ensure the executable has the correct permission. These steps include running the setasmgidwrap command as the "grid" user:

 

root@dbvlin101[/u01/app/oracle/product/12.1.0/db_1/bin]: ls -altr oracle

-rwsr-s--x 1 oracle oinstall 282183593 Jul 28 17:49 oracle

root@dbvlin101[/u01/app/oracle/product/12.1.0/db_1/bin]: cd

root@dbvlin101[/root]: su - grid

grid@dbvlin101[/home/grid]: . oraenv

ORACLE_SID = [grid] ? +ASM

The Oracle base remains unchanged with value /u01/app/grid

grid@dbvlin101[/home/grid]: setasmgidwrap o=/u01/app/oracle/product/12.1.0/db_1/bin/oracle

grid@dbvlin101[/home/grid]: cd /u01/app/oracle/product/12.1.0/db_1/bin/

grid@dbvlin101[/home/grid]: ls –al oracle

-rwsr-s--x 1 oracle asmadmin 282183593 Jul 28 17:49 oracle

 

Primary Server: Primary Database

On the primary database server, it is assumed that you have already created a primary database and that this database is running without any issues. 

No outage is required during the installation of Dbvisit Standby.

For Oracle RAC environments, all the RAC instances should be running during the initial Dbvisit Standby installation.

 

Primary Database: Archivelog Mode

To enable the use of a standby database, your primary database must be in archivelog mode.  To determine if database is in archive log mode run SQL command: "sql> archive log list"

Example:

SQL> archive log list;
 Database log mode Archive Mode
 Automatic archival Enabled
 Archive destination USE_DB_RECOVERY_FILE_DEST
 Oldest online log sequence 21568
 Next log sequence to archive 21571
 Current log sequence 21571

 

If the database is not in archivelog mode you can use the following to enable it.  Please note this requires an outage.  Also make sure you have sufficient space in your fast/flash recovery area:

 

SQL > connect / as sysdba
SQL > shutdown immediate
SQL > startup mount
SQL > alter database archivelog;
SQL > shutdown immediate;
SQL > startup
SQL > alter system switch log file;
 

 

For more details on enabling archivelog mode, please see the Oracle Documentation.

Dbvisit Standby Software Owner

Dbvisit must be installed with the same account that is running the Oracle Database software, and in most Unix systems this will be the "oracle" Unix user account. The user should also be part of the Oracle DBA group, which in most cases is the "dba" group on Unix.

Dbvisit Standby does not make use of the Oracle Listener for database connections. All connections to the database are local connections, for example:

SQL> connect / as sysdba
Connected.

 

The sys database account can also be used by Dbvisit, example:

SQL> connect sys/syspassword as sysdba
Connected.

 

If operating system authentication is not allowed and user (sys) authentication is used, the credentials should be specified in the Dbvisit Database Configuration (DDC) file.

NOTE: In case either primary or standby databases use ASM storage, the user that installed Dbvisit Standby should be able to connect to the ASM instance as sysdba. 

 

Email Server Details

Dbvisit Standby uses email for alert notifications.  Dbvisit Standby comes with its own mail client. The SMTP server needs to be specified so that Dbvisit Standby knows where to send the emails to. The SMTP server is usually in the format: mail.<your companyname>.com

NOTE: Sendmail can also be used if Dbvisit is installed on Unix systems with sendmail enabled. In this case, the SMTP server is not required.

 

Ensure that the primary and standby servers are known to each other.

It is recommended to make sure that both systems are aware of the others name and IP address.  Using DNS entries or using entries in the “hosts” file can be used to do this.

Example entries in host file (note that xxx.xxx.xxx.xxx is IP addresses):

 

xxx.xxx.xxx.xxx     your_primary_server_name
xxx.xxx.xxx.xxx     your_standby_server_name

 

 

Required Firewall Ports are open

Dbvisit Standby version 7 makes use of Dbvnet by default.  It is still possible to make use of SSH for communication if required.  It is recommended that you make sure the following ports are open on each of the servers to allow for communication between them, as well as to allow the end user to connect to the Dbvisit Web GUI:

  • Dbvisit Neworking (Dbvnet)
    • Default port used is 7890
  • Dbvisit GUI (Dbvserver)
    • Default port used for HTTP is 8081 
    • Default port used for HTTPS is 8443
    • If port 8081 is used it will attempt to make use of port 8082
  • If SSH is used, port 22 should also be open

Note: in most cases you will need to allow these ports to be open in your IPTABLES configuration if you are using Linux, or you will have to update your Windows firewall settings if a Windows is used.

 

Required Operating System packages

(Linux)

As of Dbvisit Standby version 7.0.10, the following package and dependencies must be installed when using Oracle Linux 6 64bit or Red Hat Enterprise Linux 6 64bit:

  • glibc 

If you do not install these packages and their dependencies, you will get errors during Dbvisit Standby installation similar to the following (this is due to glibc.i686 not being installed on OEL6 or RHEL6):

/lib/ld-linux.so.2 bad ELF interpreter no such file or directory

 

It is required for 64bit versions of OEL6 and RHEL6 that you install the glibc.i686 package and ALL its dependancies.

If you have your YUM repositories configured you can use the following commands to install these required packages and dependancies:

 yum install glibc.i686

Dbvisit Standby Base Directory

It is strongly recommended that you make use of the default location when installing Dbvisit Standby. The default Dbvisit Standby installation location is known as the Dbvisit Base directory.

On Unix it is important to pre-create this directory and make sure the owner and group used for this directory is the same as what was used for the Oracle Database Software installation. In most cases this will be the unix user "oracle" and group "oinstall" or "dba" 

On Unix the default location is: /usr/dbvisit

On Windows the default location is: c:/Program Files/Dbvisit

Note:  It is recommended you have minimum 200MB free space in this location to cater for the installation (approx. 75MB) as well as the trace files generated during normal operation.

 

Web Based ReportingIf you are looking at using the Web Based front-end it is recommended that your flash plugin is installed and up to date as this is used by the Reporting screen Graphs.
Ensure that the default temp directory on Unix example /tmp does not have noexec option specified

When installing Dbvisit Standby and you get the following error "Error: Can't locate libperl.so" example:

 

oracle@dbvlin103[/home/oracle/7.0/dbvisit/installer]: ./install-dbvisit
Error: Can't locate libperl.so
Make sure the ActivePerl bin directory is in your PATH
PATH=/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin

 

Background Information:

When Dbvisit Standby is executing including Dbvnet and Dbvserver, temporary files are extracted and used from the default system temp location. 

On most Unix system this will be /tmp

The problem in this case is that the /tmp mount point was mounted using the "noexec" option.  

Using the mount command you can quickly review the settings:

oracle@dbvlin103[/home/oracle/7.0/dbvisit/installer]: mount |grep tmp
tmpfs on /dev/shm type tmpfs (rw,size=2G,rootcontext="system_u:object_r:tmpfs_t:s0")
tmpfs on /tmp type tmpfs (rw,noexec,size=2G)

 

In some cases where environments are locked down, this might be seen.

 

Solution:

There are two possible options to get past this.

 

1.  Ask the system administrator to mount the /tmp filesystem without the "noexec" option.

2.  Create a new temporary directory and set the TMPDIR environment variable to point to this location, example:

 

oracle@dbvlin103[/home/oracle/7.0/dbvisit/installer]: mkdir /home/oracle/tmp
oracle@dbvlin103[/home/oracle/7.0/dbvisit/installer]: export TMPDIR=/home/oracle/tmp
oracle@dbvlin103[/home/oracle/7.0/dbvisit/installer]: ./install-dbvisit
-------------------------------------------------------------------------------
Welcome. Your Dbvisit product is going to be installed in a moment.
It will be required by you to enter some configuration parameters
during installation.
-------------------------------------------------------------------------------
It is recommended to make a backup of our current Dbvisit software
location for rollback purposes.

>>> INSTALLATION DIRECTORY

Please specify the Dbvisit main installation directory.

The default directory is "/usr/dbvisit".

Note: the various Dbvisit products and components - such as Standby,

Replicate, Dbvnet, and Dbvserver - will be installed in the appropriate
subdirectories of this path.

Enter a custom value or press ENTER to accept default [/usr/dbvisit]:

>
 

If you have to look at using TMPDIR option you will need to make sure you update the .bash_profile or .profile or other environment configuration files to ensure that this path is set before you execute Dbvisit Standby processes.

 

If you have reviewed the above requirements and your system meets these, you are now ready to start the Dbvisit Standby installation.

 

Watch this explanatory video for an alternative overview of our Dbvisit Standby Installation Prerequisites: