18c Database : Readonly Home and Password File Location Changes

In this post we cover two aspects of new features in 18c.

Readonly Oracle Home:

A read-only Oracle home separates the software from the database configuration information and log files. This separation enables you to easily share the software across different deployments. A read-only Oracle home also simplifies version control and standardization.

To enable the readonly oracle home, Run the roohctl Script

1.Go to the bin directory
$ cd /u01/app/oracle/product/18.0.0/dbhome_1/bin
2.Run the roohctl script to enable read-only Oracle home.
$ ./roohctl -enable

Password File Location:

Starting 18c, Oracle automatically searches the $ORACLE_BASE/dbs first for password files instead of $ORACLE_HOME/dbs, this facilitate the readonly Oracle Home feature to have the home in readonly but other files are out side of Home for read/write operations.

In the Oracle Cloud 18c, I tested for readonly oracle home, initially it failed with below error

[oracle@db18c-se-si bin]$ ./roohctl -enable
Enabling Read-Only Oracle home.
Cannot enable Read-Only Oracle home in a configured Oracle home.
The Oracle Home is configured with databases 'orcl'.
The Oracle Home is configured with listeners 'LISTENER'.

So I decided to comment out /etc/oratab and remove listener.ora file and give a go, and that worked.

[oracle@db18c-se-si bin]$ ./roohctl -enable
Enabling Read-Only Oracle home.
Update orabasetab file to enable Read-Only Oracle home.
Orabasetab file has been updated successfully.
Create bootstrap directories for Read-Only Oracle home.
Bootstrap directories have been created successfully.
Bootstrap files have been processed successfully.
Read-Only Oracle home has been enabled successfully.
Check the log file /u01/app/oracle/cfgtoollogs/roohctl/roohctl-180317AM065000.log.
[oracle@db18c-se-si bin]$

Disabled back

[oracle@db18c-se-si bin]$ ./roohctl -disable
Disabling Read-Only Oracle home.
Update orabasetab file to disable Read-Only Oracle home.
Orabasetab file has been updated successfully.
Read-Only Oracle home has been disabled successfully.
Check the log file /u01/app/oracle/cfgtoollogs/roohctl/roohctl-180317AM065204.log.
[oracle@db18c-se-si bin]$

In fact, this feature is available in 12c R2 as well, however it does not given the error that Database/Listener are configured

[oracle@db12c-se-si bin]$ ./roohctl -enable
Enabling Read-Only Oracle home.
Update orabasetab file to enable Read-Only Oracle home.
Orabasetab file has been updated successfully.
Create bootstrap directories for Read-Only Oracle home.
Bootstrap directories have been created successfully.
Read-Only Oracle home has been enabled successfully.
Check the log file /u01/app/oracle/cfgtoollogs/roohctl/roohctl-180317AM065422.log.
[oracle@db12c-se-si bin]$

 

What it mean is we cannot have the DB or Listeners configured with that home before we keep the Home in readonly.

-Thanks

Suresh