Validated Infrastructure for Oracle Linux and Oracle VM   Leave a comment

If you are thinking about building  Oracle Linux or Oracle VM based systems for your Oracle databases, for example  building a private cloud type of system to consolidate your databases,. have you thought about the hardware  infrastructure  that your rest of platform will be built upon. One thing that you need to make sure is that the infrastructure stack is certified and validated for the software platform stack such as Oracle Linux/Oracle VM and the Oracle database.

The nice thing about this is that as a customer, you should not spend  your resources for this complex and time consuming certification and validation process  as various hardware vendors will partner with Oracle to establish the validated configurations. But you need to make sure that you select the proper infrastructure and OS  based on the validated configurations.  Since starting  working on Oracle Linux and Oracle VM in 2009 ,  it has been my team’s responsibility to work with Oracle Linux and Oracle VM team to certify  and validate  Infrastructure such as  Dell servers, storage and networking components  with Oracle VM and Oracle Linux Unbreakable Kernel (UEK). And we posted the validated configurations on Oracle Linux and Oracle VM  Validated Configuration (OVC) website : .

This website documented pre-tested , validated configurations and best practices of running Oracle Linux and Oracle VM on various infrastructure  such as Dell PowerEdge servers, Dell Storage and Network. With each of the validated configuration, customers  can run their  production Oracle database either with  Oracle Linux or Oracle VM as a  database platform.

You can get a completed list of the configurations with this link: On this link, you can type a Hardware vendor name and you can get a list of the validated configuration with various hardware. For example,. if you  type Dell to search, it will come back with  55 configurations as today (10/19/2016). The list consists of the latest servers such as Dell PowerEdge R930 and various Dell Storages.


This is what a specific configuration looks like:



OOW2016 Part 2: What I presented and what I learned   Leave a comment

Working in Progress, will come up in 2-3 days

Posted October 4, 2016 by kyuoracleblog in Uncategorized

OOW2016 Part 1: Preconference Oracle ACED Product Briefing at Oracle HQ   Leave a comment

The annual Oracle technology event Oracle OpenWorld (OOW) was held on Sept 18-22 in San Francisco. As usual my trip to this conference really consists of two parts: Preconference Oracle ACE Director product briefing (my 7th product briefing )  on Sept 15-16  and OOW conference  (my 11th OOW) on Sept 18-22. I am writing these two blogs to share my experience of this 7 days conference.

The preconference Oracle ACE Director Product briefing was held at the Oracle Conference center of Oracle HQ at Redwood shores, California. The event agenda consisted of two full days of presentations by Oracle executives and product managers. The Product briefing started at 9:00am of Spet 18  with the executive presentation by Thomas Kurian , the president of Oracle product development. In his one hour presentation, Thomas Kurian gave a very broad summary of the Oracle’s IaaS/Cloud Vision, Strategy, Roadmap , which covered a good amount of new development that would be announced in the upcoming Oracle OpenWorld 2016 in a next few days. Thomas’ talk was followed by two IaaS presentations that covered Oracle latest IaaS Cloud service: 1) IaaS architecture by Mark Cavage , vice president of Engineering at Oracle ; 2) the engineering overview of IaaS implementation by Deepak Patil, Vice president, Development at Oracle. The new Oracle IaaS service has built in some high performance features such as high bandwidth (Tb/s) and low round-trip-time (< 1ms) between Oracle Cloud data centers . It uses Software Defined networks  (SDN) technologies which provides the flexibility of network in the same way as Hypervisor provides flexibility of compute. In the compute cloud service, the  IaaS offers the Bare metal based compute service, the Virtual machine based compute service as well as the Container based compute service.


(Oracle President for product development Thomas Kurian in Oracle ACED product briefing )

One of interesting presentations was given by Navin R. Thadani, Products at Ravello Systems at Oracle. Navin introduced one of new products recently acquired by Oracle: Ravello. This product helps customers by lifting the applications running on VMware from customer on-premise data center to Oracle public Cloud simply without any change. Another presentation was about Oracle  Oracle  Database 12c Release 2 Cloud First release, which was later officially announced by Larry at Oracle OpenWorld 16.

In the afternoon, I also attended a special session about Oracle Linux and virtualization update (my favor subject), presented by my good friend Honglin Su, Sr. Direct  of Product Management for Oracle Linux and Virtualization. A lot of new features about Oracle UEK kernel, and Oracle VM were presented, such as support for Ksplice , OpenStack for Oracle Linux, Docker and Oracle Cloud container Registry, in UEK R4. QU2 . Here is the photo taken after the session:


(With Oracle Linux and Virtualization : Honglin Su (Right) and his colleague (Left) and myself (middle))

On the second day, there were more Oracle cloud related presentations which covered a variety of Oracle public cloud topics: DevOps at Oracle public cloud, Big data in Oracle cloud, Oracle Golden Gate in the cloud, Oracle PaaS cloud. Oracle Management cloud service. Etc.

In summary, from this Oracle product briefing, we can see that Oracle has put so much focus on Oracle Cloud in the past year. I was expecting to give more details about Oracle Cloud from the  rest of Oracle OpenWorld conference.

Oracle ACE director product briefing not only provides us a chance to get the exposure on the Oracle latest technology development, it was also a great network opportunities for us. This is the annual event where more 70 Oracle ACE Directors  got together to discuss many their favor technologies and establish the professional network and the friendship among us. The following photo is the picture of all Oracle ACED directors who attend this preconference product briefing event at  Oracle Conference center before Oracle OpenWorld 2016.



(Oracle ACE directors at Oracle conference center)

The networking opportunity event extended to Oracle ACE and Oracle associate ACE (for more details about Oracle ACE directors, Oracle ACE and Oracle ACE associate , refer to Oracle ACE program link : ).

The following is the photo of Oracle ACE directors, Oracle ACE and Oracle ACE associate taken at San Francisco Pier 39 where Oracle ACE program hosted the annual Oracle ACE dinner for all the Oracle ACED/ACE/ACE associates who attended Oracle OpenWorld 2016.




Posted October 4, 2016 by kyuoracleblog in Uncategorized

I will be presenting at Oracle OpenWorld 2016   Leave a comment


At the upcoming Oracle OpenWorld 2016, I will be co-presenting  two sessions:

  1. Discovering Oracle Cloud [UGF5475],  Tariq, Farooq, Kai Yu, Sunday, Sep 18, 3:30 p.m. – 4:15 p.m. | Moscone West – 2009                                                                                               

This vibrant session explores how your company could make the best use of all Oracle Cloud options available, including backup in the cloud, and what benefits it can bring to your organization. Discover how Oracle Cloud works, looks, and feels in only 45 minutes , the link to download the presentation of this session:  

    2. Leveraging Oracle Database 12c Release 2 Multitenant Features [CON3075], Thursday, Sep 22, 12:00 p.m. – 12:45 p.m. | Park Central – Metropolitan I

Oracle Database 12c Release 2 offers so many new multitenancy features that only a panel of Oracle ACEs can do them justice. In this session Oracle ACEs Jim Czuprynski, Andy Colvin, Kai Yu, Anuj Mohan, and Deiby Gomez provide their experiences with the latest multitenancy features in Oracle Database 12c Release 2. Hear about client implementations as well as extensive beta testing and see how any Oracle DBA can take immediate advantage of these new capabilities. All source code and practical examples will be available immediately after the presentation.
The link to download the presentation of this session:
Refer to Oracle Openworld session catalog: ( yu&search.event=oracleopenworld)

Proud of be a Part of Dell Technologies   Leave a comment


Posted September 7, 2016 by kyuoracleblog in Uncategorized

Troubleshooting case study : Oracle RAC database is open but not accessible through listener due to some old unused diskgroup being removed   Leave a comment

The Issue:

I would like to use this blog to show how a recent database issue was resolved. The issue started when the application was not able to connect the database . Here is the part of log from the Oracle OBIEE application:

<Mar 29, 2016 11:48:58 AM CDT> <Warning> <JDBC> <BEA-001129> <Received exception while creating connection for pool “raframework_datasource”: Listener refused the connection with the following error:

ORA-12514, TNS:listener does not currently know of service requested in connect descriptor

The Troubleshooting steps

 1) Test the sqlnet and it didn’t show any error message:

[oracle@inmem2 admin]$ tnsping POCDB

TNS Ping Utility for Linux: Version – Production on 26-MAR-2016 20:22 :18

Copyright (c) 1997, 2014, Oracle. All rights reserved.

Used parameter files:

Used TNSNAMES adapter to resolve the alias

Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = inmem-sc an)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = pocdb.dbase.lab)))

OK (0 msec)

2) Test the database connectivity and showed the failed connection to the database:

[oracle@inmem2 admin]$ sqlplus biuser/<password>@pocdb

SQL*Plus: Release Production on Sat Mar 26 20:22:23 2016

Copyright (c) 1982, 2014, Oracle. All rights reserved.


ORA-12514: TNS:listener does not currently know of service requested in connect


3) check listener and it looks fine

[oracle@inmem1 ~]$ lsnrctl status

LSNRCTL for Linux: Version – Production on 26-MAR-2016 20:39:13

Services Summary…

Service “+ASM” has 1 instance(s).

Instance “+ASM1”, status READY, has 1 handler(s) for this service…

Service “pocdb.dbase.lab” has 1 instance(s).

Instance “pocdb1”, status READY, has 1 handler(s) for this service…

Service “pocdbXDB.dbase.lab” has 1 instance(s).

Instance “pocdb1”, status READY, has 1 handler(s) for this service…

The command completed successful

4) Check the database sysdba login:

Database is up:

[oracle@inmem1 ~]$ sqlplus

SQL*Plus: Release Production on Tue Mar 29 09:41:28 2016

Copyright (c) 1982, 2014, Oracle. All rights reserved.

Enter user-name: / as sysdba

Connected to:

Oracle Database 12c Enterprise Edition Release – 64bit Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Advanced Analytics and Real Application Testing option

5) However check the database status from srvctl and found that the database was marked down on both nodes:

[oracle@inmem2 admin]$ srvctl status database -d pocdb

Instance pocdb1 is not running on node inmem1

Instance pocdb2 is not running on node inmem2

Tried to bring it up and failed as it failed to bring up resource ‘ora.DATA.dg’

[oracle@inmem1 ~]$ srvctl start database -d pocdb

PRCR-1079 : Failed to start resource ora.pocdb.db

CRS-2674: Start of ‘ora.DATA.dg’ on ‘inmem2’ failed

CRS-2632: There are no more servers to try to place resource ‘ora.pocdb.db’ on that would satisfy its placement policy

CRS-2674: Start of ‘ora.DATA.dg’ on ‘inmem1’ failed

6)  Check the CRS resource status and found that ora.DATA.dg and ora.pocdb.db were offline:

[grid@inmem1 ~]$ crs_stat











Check the dependencies of ora.pocdb.db

7) Check the resource dependency. It shows the database pocdb has dependency on ora.DATa.dg for this startup process.

[grid@inmem1 ~]$ crsctl status resource ora.pocdb.db -f




START_DEPENDENCIES=hard(ora.DATA.dg, ora.SAN_DATA2.dg) pullup(ora.DATA.dg, ora.SAN_DATA2.dg) weak(type:ora.listener.type,global:type:ora.scan_listener.type,uniform:ora.ons,global:ora.gns)

It shows the POCDB has dependency on DATA diskgroup, but DATA diskgroup is no longer available in ASM instance:

SQL> select NAME, STATE  from v$asm_diskgroup;









6 rows selected.

So we need to remove the this dependency


The key is to remove this dependency so that we can restart the database through srvctl and make sure that the status of the database resource ora.pocdb.db is shown as ONLINE

1) Reregister pocdb in as a CRS resource

Remove the database first:

[oracle@inmem1 ~]$  srvctl remove database -d pocdb

Remove the database pocdb? (y/[n]) y

Then add the database back:

[oracle@inmem1 ~]$ srvctl add database -d pocdb -o /u01/app/oracle/product/12.1.0/dbhome_1

[oracle@inmem1 ~]$  srvctl add  instance -d pocdb -i pocdb1 -n inmem1

[oracle@inmem1 ~]$ srvctl add  instance -d pocdb -i pocdb2 -n inmem

2) Check the dependency status:

[grid@inmem1 ~]$ crsctl status resource ora.pocdb.db -f





3) Startup the database :

[oracle@inmem1 ~]$ srvctl start database -d pocdb

Check the database status

[oracle@inmem1 ~]$ srvctl status database -d pocdb

Instance pocdb1 is running on node inmem1

Instance pocdb2 is running on node inmem2

Test the database connectivity

[oracle@inmem1 ~]$ sqlplus biuser/password@pocdb

SQL*Plus: Release Production on Tue Mar 29 11:51:39 2016

Copyright (c) 1982, 2014, Oracle. All rights reserved.

Connected to:

Oracle Database 12c Enterprise Edition Release – 64bit Production

With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,

Advanced Analytics and Real Application Testing options

The Oracle BI application is no longer having connectivity issue.

Posted March 29, 2016 by kyuoracleblog in Uncategorized

IOUG Spotlight for March 2016   Leave a comment

Each month, the Independent Oracle Users Group ( IOUG)  spotlights  and give an inside look at their life.  It is  a great honor that  IOUG picked me for the March 2016 IOUG Member Spotlight as this link: Here are some of contents from the link:

IOUG Member Spotlight


Join IOUG each month as we shine the spotlight on one of our members. Learn fun facts about what inspires our members, what they do for fun and how they got started in their careers.

March 2016 – Kai Yu

What’s your current job and title?

I am a Senior Principal Engineer at Dell Enterprise Solutions Engineering. My responsibilities include architecting, implementing enterprise database solutions and cloud based solutions.

What is your favorite moment of your career so far?

Over two decades, I have worked on various technology and enjoyed every moment when my work was put into products or engineering solutions. One particular example was that in 2008, I put together a database consolidation model and performed the performance studies that helped a customer consolidate a few dozens of databases from multiple small IT sites into a centralized Oracle Grid architecture in the data center. For this I received the “Customer Experience Legend Award,” the most prestigious award from the Dell Senior Executives.

What was your childhood dream job?

Mathematician or aerospace engineer, but ended up computer science career which I found more interesting.

How long have you been a member of IOUG? What’s your best experience thus far?

Since 2008, when I started to get involved with the IOUG Oracle RAC SIG. Since then I have really enjoyed engaging with IOUG activities such as running a few IOUG technology boot camps at COLLABORATE conferences. One of my best experience was to co-found the IOUG Cloud Computing SIG. I got a chance to work with many great talents and industry experts to establish this important platform that is dedicated to sharing expertise and experiences on Cloud Computing.

What advice do you wish someone had given you when you first started your career as a technologist?

I wish someone had given me some advice about the direction which technology was moving to and how to better pursue the technical career.

What features or products are on your wish list and why?

As SSD (Solid State Drive) is getting more and more adapted as the database storage, I would like to see that database systems introduce some new architecture and features that are specially designed to better leverage SSDs great performance.

What is the biggest technical and/or business challenge you have faced, and how did you overcome it?

It can be challenging to implement some of the latest technology for business. One particular case was implementing a cloud service POC system using a beta release of Oracle Enterprise Manager 12c Cloud Management.  Luckily, I worked with the Oracle EM12c engineering team very closely and we were able to overcome many technical challenges and successfully complete the POC. As a result, we presented the POC at Oracle OpenWorld 2012 when Oracle released Oracle EM12c Cloud Control.

How do you stay active? How did you discover that activity?

I enjoy travelling to different places around the world to learn different culture and making friends in the global technology community. Besides that, my favorite activity is swimming. Although I’ve liked swimming since my childhood, I really found myself passionate about it when I learned how to build the endurance for a distance swimming.

What’s your favorite film? Any memorable moments? Any favorite quotes?

The 2014 film: “The Theory of Everything”

A favorite quote: “There should be no boundaries to human endeavor. However bad life may seem, where there is life, there is hope.”

What piques your passion in technology?

When I was in a software developer role for more than 20 some years, I was fascinated by Oracle Database technology. Ten years ago, after moving to the enterprise engineering role, I found myself a new interest on infrastructure that Oracle database is based on such as Linux OS, servers, storage and networking. These experiences allow me to see the big picture of computing technology and how these technologies are moving forward—that is truly fascinating.

LinkedIn: Kai Yu

Twitter: ky_austin1


Posted March 3, 2016 by kyuoracleblog in Uncategorized