DURING INSTALLATION OF 11G GRID CONTROL: AGENT CONFIGURATION ASSISTANT FAILS ON SECURE STEP

During 11g grid control installation, at configuration step second last step (Agent Configuration) was failing at secure agent.

                   According to Oracle support its a know bug 9950142 and its solution is simply restarting oms at $ prompt and then press retry at OUI. 

Steps are below

                  1) cd /u01/app/oracle/Middleware/oms11g/bin

                  2) emctl stop oms

                  3) emctl start oms

                  4) press retry at Oracle Universal Installer

Linux Error: 29 Illegal Seek ....when trying to start lisnr

When try to start listener

LSNRCTL> start
Starting /home/oracle/oracle/product/10.2.0/db_1/bin/tnslsnr: please wait...

TNS-12537: TNS:connection closed
TNS-12560: TNS:protocol adapter error
TNS-00507: Connection closed
Linux Error: 29: Illegal seek

Solution:

Include in /etc/hosts file 
127.0.0.1 localhost.localdomain localhost

ORACLE_MIDDLEWARE_HOME_LOCATION

 "ORACLE_MIDDLEWARE_HOME_LOCATION ..specified oracle middleware home is not installed in this host"

                    During 11g grid control Installation, I has to changed my Linux hostname after weblogic  server 10.3.2 installation, then at time of grid control installation, I got error message mentioned above.

                    Upon detailed investigation I foud that Once the hostname is changed after weblogic installed correctly then I required to check the registry.xml file for the hostname parameter and update it as per the new hostname.

registry.xml File path is:
/u01/app/oracle/Middleware/registry.xml 

Locate entry 

<host home = 
and ensure that it has the correct hostname.

Cheers,

Farrukh Salman.