Slow tnsping Response and Slow Connections to the Database

We can use TNSPING utility to check connection with the database, for the client side. If you observe that TNSPING is returning very late/slow, and application connection is also very slow, there are a couple of things that you can check. First thing is to use network speed. You can use OS command “ping” to check if network is stable and response is fast enough. You can also seek help of your network team to verify if network is working as expected, and no latency or packet loss is being observed.

ORA-12170 : TNS:Connect timeout occurred

If your application (or SQLPLUS) is returning ORA-12170 while connecting to the database, there are a few things that you can verify in order to find out the root cause of the issue, and implement a solution. Although sometimes it is quite difficult to find out the root cause, I will discuss some major and quite common causes of this error message that cause failure of application to connect with the database.

Resuming Database Upgrade Assistant after Error

If your database upgrade by database upgrade assistant is caught by a glitch, a dialogue box may appear with options of “Ignore”, or “Abort”. There could be a situation whereby you can ignore the error and continue with the upgrade process. But, before you could do this, you would need to resolve the problem that encountered, before clicking the Ignore button to continue.

Installing Oracle 12c R2 Database Software on Linux 6 and Linux 7

In this article I would explain how to install Oracle 12c R2 database software on Linux 6 and Linux 7. If you want to use ASM as storage and/or Oracle Restart feature, you would need to install 12c R2 Grid Infrastructure before proceeding to install RDBMS software. You must be using at least Linux 6.4 for installation on Linux 6.

ORA-16191: Primary log shipping client not logged on standby

Password file difference is one of the biggest causes of log shipping failure from primary database to the standby. Follow this document to resolve ORA-1619. Following is what would appear in the alert log file if log shipping fails because of password file differences between primary site and standby site.

Fractured block found during backing up datafile

This error means that RMAN found an inconsistent block during the backup of a datafile. It is quite likely that on second attempt to read the block, RMAN is able to find a consistent image of the block, hence no further action would be required. But, if you need to perform a block recovery, this article will be worth reading. Alert log file will show message similar to the following when this error is reported.

ASM Disk not Accessible and not Appearing in V$ASM_DISK

If you are using ASMLib for your ASM storage and it is working perfectly fine; then, after adding a new ASM Disk you suddenly realize that although new disk is being listed by “oracleasm listdisks” command, it is still not appearing in V$ASM_DISK view. As a result, you are not able to add this new disk in your diskgroup because disk is not accessible to ASM instance. One reason of this could be that ASMLib configuration is not as it should be. Reasons could be: OS patching, oracleasm kernel driver update etc.

Installing Oracle 12c R2 Grid Infrastructure on Linux 6 and Linux 7

You need to install 12c R2 Grid Infrastructure (for a standalone server) software in order to use ASM and/or Oracle Restart feature. In the following I will explain how to install GI for a standalone server on Linux 6 and Linux 7. You must use at least Linux 6.4 for installation on Linux 6. For this installation, I am using Oracle Linux 7. 

There are only a couple of differences between the installation procedures on Linux 6 and Linux 7 which I will mention along the way.

Creating Weblogic Domain for Weblogic Server

After the installationof weblogic server, next step is to create a new weblogic domain. If you have installed weblogic server with examples, there will be a domain already configured during the installation and an application deployed. For the creation of other domain(s), you may follow the steps explained in this article.

Installing Weblogic Server 12.2 on Linux 6 Linux 7 and Windows

If you want to install full Fusion Middleware, this article will help you, otherwise keep reading this article if you wish to install weblogic server only. In this article I will explain how to install Weblogic and Coherence that is used to deploy Java applications. I did this installation on Linux, but same steps can be followed to install the weblogic server on Windows platform.