Jumbo frames in Oracle RAC

Recently we implemented jumbo frames in our RAC environment, I have read a lot about jumbo frames and how they can be helpful in a cluster based environment but never actually experienced in a real time setup.
In one of the setups recently after migration , it was basically a hardware based migration, an upgrade to more advanced servers ,post migration database was slow and there were many Cluster related events. One of the main event being "gc cr request" and "gc cr congested" , these 2 events were in large count if we query gv$session_wait view.
There was no quick solution to this event and we tried to tune a few problematic sqls, which helped in reducing this event to some extent but most of the times the average CR block Receive Time was unusual then normal and so was average current block receive time.
Finally after a few days we had implemented JUMBO Frames in our rac environment, And just after implementing these, the average CR block Receive Time came down tremendously and also gc cr request and gc cr congested event were very very less.

So Jumbo frames are very much useful as i would say, although it is not recommended by support people.

adstrtal.sh: exiting with status 1

This is one of the messages i got while starting APPS tier of e-business suite.
I am new to this thing, so checked a few things. Logged onto the database , and tried to connect with apps user which was quite successful. Then i realized that may be listener is not up, and that was the culprit. So i started listener using command adalnctl.sh start PROD and once again started Apps tier which worked now!!

Alert tab of oracle Grid Control

We have grid control installed in one of our setups. This is quite useful as you can register all your databases here and monitor them from a centralized control. One of the good things i like about this is the alert tab. By clicking on the alert tab you can easily see all the errors coming in any of the databases whether they are ORA- errors or any other.
So another useful feature and observation from my side.

DBMS_SCHEDULER

This is some task i did for the first time in one of my recent projects.
so just an another attempt to share my learning.
To create a scheduled job the syntax is -

begin
sys.dbms_scheduler.create_job(job_name => 'test_job',
job_type => 'PLSQL_BLOCK',
job_action => 'BEGIN DBMS_STATS.gather_schema_stats(''ABC''); END;',
repeat_interval => 'FREQ=DAILY;BYHOUR=21;BYMINUTE=45;BYSECOND=0',
start_date => sysdate,
job_class => 'DEFAULT_JOB_CLASS',
comments => 'gather stats job',
auto_drop => TRUE,
enabled => TRUE);
END;

initializing oracle ASMLib driver : FAILED , Loading module "oracleasm": Unable to load module "oracleasm"

I came across this problem recently while installing Oracle RAC on one of the systems.

[root@rac1]# /etc/init.d/oracleasm configure
Configuring the Oracle ASM library driver.

This will configure the on-boot properties of the Oracle ASM library
driver. The following questions will determine whether the driver is
loaded on boot and what permissions it will have. The current values
will be shown in brackets ('[]'). Hitting without typing an
answer will keep that current value. Ctrl-C will abort.

Default user to own the driver interface [oracle]: oracle
Default group to own the driver interface [dba]: dba
Start Oracle ASM library driver on boot (y/n) [y]: y
Fix permissions of Oracle ASM disks on boot (y/n) [y]: y
Writing Oracle ASM library driver configuration: [ OK ]
Loading module "oracleasm": Unable to load module "oracleasm"
[FAILED]

The correct place to look for erorr was /var/log/messages.
here i found the error Module oracle ASM not found.

I did a rpm -qa | grep oracleasm on the system and found 3 asm packages installed.
oracleasm-2.6.9-89.EL-2.0.5-1.el4.i686.rpm,
oracleasmlib-2.0.4-1.el4.i386.rpm,
oracleasm-support-2.1.3-1.el4.i386.rpm


The following package was missing -->
oracleasm-2.6.9-89.ELsmp-2.0.5-1.el4.i686.rpm

I installed the above given package with -->

rpm -ivh oracleasm-2.6.9-89.ELsmp-2.0.5-1.el4.i686.rpm
Preparing... ########################################### [100%]
1:oracleasm-2.6.9-89.ELsm########################################### [ 100%]

afterwards again tried to configure Oracle ASM

[root@rac1]# /etc/init.d/oracleasm configure
Configuring the Oracle ASM library driver.

This will configure the on-boot properties of the Oracle ASM library
driver. The following questions will determine whether the driver is
loaded on boot and what permissions it will have. The current values
will be shown in brackets ('[]'). Hitting without typing an
answer will keep that current value. Ctrl-C will aborts.

Default user to own the driver interface [oracle]: oracle
Default group to own the driver interface [dba]: dba
Start Oracle ASM library driver on boot (y/n) [y]: y
Fix permissions of Oracle ASM disks on boot (y/n) [y]: y
Writing Oracle ASM library driver configuration: [ OK ]
Initializing the Oracle ASMLib driver [ OK ]
Scanning the system for Oracle ASMLib disks [OK]

RW-50016 Error: - {0} was not created during rapidinstall

ERROR LOGIN PAGE
-------------------------
checking URL = http://.:8000/OA_HTML/AppsLogin
RW-50016: Error: - {0} was not created

Finally when i thought i have solved all errors, i came across this new error at the end on installation. Now am trying to solve this one, and will post the solution as soon i come across one. Anyhow installation was smooth till now, its just this error i had come across at the end, but it took me a lot of time to complete installation since am also installing vision database for test purpose and am that too on vmware.

I tried one of the solutions that i came across on other sites, and changed the entries in /etc/hosts.
127.0.0.1 localhost

Now i started install again and one of the error that was previously coming - JSP page could not be displayed has stopped coming.

Let's hope the other error also stops coming.

I will update this post soon with some results.