How to determine CRS_HOME

In the environment of the cluster owner or some scripts, you may want to set a variable for the cluster installation usually called CRS_HOME, GRID_HOME or simly ORACLE_HOME.
I like to do that in an automatic and non-static way. But be careful, this means it could go wrong or is being set to an unexpected value.
The main part of this post is how get the information and how to check for an acceptable value. Continue reading “How to determine CRS_HOME”


local_listener is set to a wrong port

The parameter local_listener of the asm instance is maintained by the clusterware and sometimes set to a wrong value. A port which is higher then the defined port of the local listener.

SYS@+ASM2> show parameter local_li
------------------------------------ ----------- ------------------------------
local_listener string (ADDRESS=(PROTOCOL=TCP)(HOST=XX.XX.XX.XX)(PORT=1526))

I faced the bug only in the following configuration:

  • cluster installed with version
  • patch level newer 160119
  • more then 2 cluster interconnects
  • FlexASM

Continue reading “local_listener is set to a wrong port”

Change Exadata Passwords

To change all password inside a Exadata is a lot of manual work. So i wrote a small script! You can find it here. The script should run on the first db node and change all password to the one read from the std in. Continue reading “Change Exadata Passwords”


In MOSC I read about OraTcpTest and had a short look at MOS note 2064368.1 . The scope of the tool is to measure network performance for Dataguard environments.
In the past I used iperf – a default Unix tool – but it has to be installed and it’s hard to set the options exactly matching the database. Often the results were not the same as the database ones. OraTcpTest should do it better. Continue reading “OraTcpTest”

Exadata storage reconfiguration with empty DGs

Changing the size of your disk groups (DG) is quite easy if the disk groups are empty. if the total amount of space used in all DGs is less then the smallest DG it’s possible to change the size. it’s like playing towers of Hanoi, you must move your data several times. This is not described here. Here you find instructions to change the size with empty DGs. Continue reading “Exadata storage reconfiguration with empty DGs”

long running script without nohup

You started a long running script and didn’t used nohup? No Problem!
To protect the script against a break caused by i.e. network errors, I usually use nohup. You have the output available in nohup.out. If you already started the script, it’s to late for nohup, but you can disown the job from your shell: Continue reading “long running script without nohup”


orachk is nothing new and was former known as raccheck, long time ago and the functionality increased a lot! It checks your environment for possible wrong configurations and best practices from oracle. The number of checks increase with each version. here you can see all the checks. You can check an existing installation or improve your standard configuration with the recommendations. I like to use it, after a cluster setup or upgrade or operating system upgrade. It’s not limited to Database, Clusterware or Operating System, but in this blog it is. Main MOS Note and Doku. Exachk is an own tool, but belongs to the same family. Continue reading “orachk”