Tuesday, March 26, 2013

Applying Hot Patch in Oracle Database 11203.

Online Patches for the RDBMS

A regular RDBMS patch is comprised of one or more object (.o) files and/or libraries (.a files). Installing a regular patch requires shutting down the RDBMS instance, re-linking the oracle binary, and restarting the instance; uninstalling a regular patch requires the same steps.

On the other hand, an online patch is a special kind of patch that can be applied to a live, running RDBMS instance. An online patch contains a single shared library; installing an online patch does not require shutting down the instance or relinking the oracle binary. An online patch can be installed/un-installed using Opatch (which uses oradebug commands to install/uninstall the patch).

Online patches are currently only supported for the RDBMS, i.e. the oracle binary.

How does Online Patching differ than traditional patches?

1. Online patches are applied and removed from a running instance where traditional patches require the instances to be shutdown.
2. Online patches utilize the oradebug interface to install and enable the patches where traditional diagnostic patches are linked into the "oracle" binary.
3. Online patches do not require the "oracle" binary to be relinked where traditional diagnostic patches do.
4. There is additional memory consumption and process start time penalty for online patches.

I downloaded and unzipped a patch in "/u01" location.

Lets set the PATH to the OPatch path so that we can run the OPatch utility from the downloaded dir.

Now check whether the patch is an Online Patch.

Note. There might be "-is_online_patch" not tell you about correct information whether is it Online or not. So sometime it is better to look into "README" text.

Syntax to apply online patch.

opatch apply online -connectString <SID>:<USERNAME>:<PASSWORD>:<NODE>

Crosscheck the installed patch into alert log and PMAP.

Excerpt from PMAP.

In case to Rollback the Online Patch.



  1. Hi Rhohit ;

    Good information. Screns Shots well.
    Can you provide any link for 10g related to online patches vs Traditional patches ..

    Thanks ..

  2. Hi Rohit,

    Good work, keep it up. One suggestion regarding the images, rather than putting the images for the logs and output, post them as text. Because when you put the output of commands and logs in textual format google search might able to understand the text and will display links to your blogs in the search.

    Ajay Bansod.

  3. Hello Ajay,

    Thanks to visit my blog and also to share your feedback with me.

    I'll consider your suggestions.

    -- rohit

  4. Nice content and good explanations...keep it up...:-)