Author: Osama Mustafa

Osama considered as one of the leaders in Cloud technology, DevOps and database in the Middle-East. I have more than ten years of experience within the industry. moreover, certfied 4x AWS , 4x Azure and 6x OCI, have also obtained database certifications for multiple providers. In addition to having experience with Oracle database and Oracle products, such as middle-ware, OID, OAM and OIM, I have gained substantial knowledge with different databases. Currently, I am architecting and implementing Cloud and DevOps. On top of that, I'm providing solutions for companies that allow them to implement the solutions and to follow the best practices.

Error: Server refused our key or No supported authentication methods available

Posted on October 21, 2017December 23, 2018 by Osama Mustafa in Cloud

If you use PuTTY to connect to your instance and get either of the following errors, Error: Server refused our key or Error: No supported authentication methods available, verify that you are connecting with the appropriate user name for your AMI. Enter the user name in the User name box in the PuTTY Configuration window.

The appropriate user names are as follows:

For an Amazon Linux AMI, the user name is ec2-user.
For a RHEL AMI, the user name is ec2-user or root.
For an Ubuntu AMI, the user name is ubuntu or root.
For a Centos AMI, the user name is centos.
For a Fedora AMI, the user name is ec2-user.
For SUSE, the user name is ec2-user or root.
Otherwise, if ec2-user and root don’t work, check with the AMI provider.

Thanks
Osama

Out Of memory , Not Enough Space Solaris 11

Posted on October 12, 2017December 23, 2018 by Osama Mustafa in Operating system

SQL> startup mount ;
ORA-27102: out of memory
SVR4 Error: 12: Not enough space
Additional information: 1671
Additional information: 16106127360
Additional information: 64424509440

The Above error appeared When trying to start Oracle 12c on Solaris 11.3, this is published bug

Bug:20635316 – 12C DATABASE INSTANCE STARTUP FAILS WITH ORA-27102: OUT OF MEMORY

Solaris using something called OSM , Optimized Shared memory You can know more about it here

To avoid this error as workaround just set the parameter

_use_osm=FALSE

Thanks

Osama

Configure AWS Command Line Interface

Posted on October 2, 2017December 23, 2018 by Osama Mustafa in Cloud

In this lesson i will show you how to configure AWS command line, and how to start working with your AWS account thru command line with very simple and basic steps :-

First of i will assume that you don’t have any user or group in your AWS console
from the AWS Console :-

From IAM ( Identity access management ) Choose Group Create Group with permission Administrator access and then hit create.

create user and add that user to the group in my case the group name shown above, save the secret key and access ID as CSV.

Now from this link here, Download AWS Command Line Interface depend on your operating system and open cmd , terminal … etc.
Now from Dos enter AWS configure and fill the information like the below:-

Open the command line and test if it’s connected to AWS now.

You can learn more about the command line from AWS documentation , if you recive the following error

“Could not connect to the endpoint URL: “https://s3.london.amazonaws.com/”

Then make sure you are on the right Region.

Thanks

Osama

failed to associate the token : AWS

Posted on September 30, 2017December 23, 2018 by Osama Mustafa in Cloud

Once you create AWS you should activate “Activate MFA on your root account”

and do that you should use your phone (Iphone, Android) download google authenticator app from the app store/Google Play once the installation is done Scan the QR and Enter the code, the code will be change automatically, if the first try not working and you receive this error ” failed to associate the token” uninstall the app and try again.

Thank you
Osama

Helping implementer and tester dealing with famous Siebel – based system messages and errors

Posted on September 22, 2017December 23, 2018 by Osama Mustafa in Articles

Upon my colleague Mohammad Altraimat i am publishing this article

let me gives you a brief about him , he is currently working with as Siebel Freelance , ensure the functionality of systems, support and train clients to use the systems and collect the requirements from the client and ensure it reflected during his career he developed this document to help people to understand more about Siebel.

You Can Share it But please mention the source of the article or you ask me to share the article with you.

You can find the article here.

Thank you
Cheers
Osama

Weblogic 101 for DBA Webinar

Posted on August 8, 2017December 23, 2018 by Osama Mustafa in Fusion Middleware

if you want to learn more about web-logic, Register now “Weblogic 101 for DBA”

i will cover different topic during the webinar to give you a better idea about the weblogic concept

Thank you
Osama

Getting Started with Pentesting

Posted on June 1, 2017December 23, 2018 by Osama Mustafa in Others

Today i received an email for the official publish for Penetration testing tutorial videos , this is another achievement will be added to my security list.

If you want to have alook on the video here

Thank you PackIT for this opportunity

Thank you
Osama

Plug and unplug PDB on the Cloud

Posted on April 5, 2017December 23, 2018 by Osama Mustafa in Cloud

You can use DBaaS Monitor to plug/Unplug in a pluggable database.

Open Dbaas Monitor like usual

Once you did this the, you will redirected to new page, in my case i have 2 PDB let’s choose one of them and try to unplug it then Plug it again.

From the Right Panel press on the Unplug new screen will be open, As you see from the below picture you should the XML path in your mind in case you need to Plug the database again , put the password same as you use it when you create PDB.