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Showing posts from May, 2020

Quick setup JDK 1.8 on Ubuntu 16.04

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In this post, I am going to write about quick setup of JDK 8 on Ubuntu Linux 16.04 assuming a fresh installation of Linux and on the top of that java needs to be installed.  Below are the steps for quick installation of JDK 1.8_x on Ubuntu Linux- 1. Login to your ubuntu linux machine as root user 2. Create a new directory at location / and provide necessary permission for read write and navigate to /u01 root@ubuntu:~ root@ubuntu:~ mkdir u01/ root@ubuntu:~ chmod 664 /u01 root@ubuntu:~ cd /u01 3. Download the Linux Compressed Archive archive from Oracle Official page-  https://www.oracle.com/in/java/technologies/javase/javase-jdk8-downloads.html Or just open the command line and use curl to download the same. For this you need a valid AuthParam because you need to be logged in to Oracle.com. So if you have and Oracle.com account just login and proceed to downloads page as specified in above link, go to respective download ...

Installation of MySQL Server 8.0 Community on Ubuntu 16.04

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Hi everyone, in this post I'll write steps to install MySQL Server 8.0 on Ubuntu Linux 16.04 version. Below are the steps to be done for the same- 1. Setting up MySQL 8.0 Repository 2. De-packaginig Debian repository 3. Installing MySQL Server 8.0 Community Version 4. Creating new user, database, permission grant 5. Connecting MySQL Server via remote MySQL Workbench  1. Setting up MySQL 8.0 Repository First we need to setup repository for MySQL 8 as Ubuntu 16.04 doesn't get shipped with the same. In order to do so, visit the APT repo page and download the *.deb package as shown below- URL- https://dev.mysql.com/downloads/repo/apt/ Alternatively use CURL via command line/ terminal as follow- cd /tmp/  wget https://dev.mysql.com/get/mysql-apt-config_ 0.8.15-1 _all.deb 2. De-packaginig Debian package Now we need to de-package the Debian package as  sudo dpkg -i mysql-apt-config_ 0.8.10-1 _all.deb On...

MySQL Connectivity Common Errors

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In this post, I'll discuss some of the common errors being encountered during connection with MySQL Server and the best possible solution worked for me or someone- Problem-1 JDBC Connection Failure java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted to reconnect 3 times. Giving up  Solution Change JDBC url to include character encoding- jdbc:mysql://localhost:3306/databaseName? useUnicode=true&characterEncoding=utf8&useSSL=false &useLegacyDatetimeCode=false&noAccessToProcedureBodies=true&serverTimezone=UTC Problem-2 Connection Java-MySql: Public Key Retrieval is not allowed Exception in thread "main" java.sql.SQLNonTransientConnectionException: Public Key Retrieval is not allowed Solution Change JDBC URL to include alllow Public Key Retrival true- jdbc:mysql://localhost:3306/databaseName? allowPublicKeyRetrieval=true &useSSL=false; Ref- https://mysqlconnector.net/connection-options/

AWS EC2 instance SSH Connection timed out for port 22

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In this post I'll describe one of the connectivity issue that I faced while working with AWS EC2 instance. Below is the problem summary, cause and solution. Let's get started... Problem I have created an EC2 Ubuntu Linux instance and configured the same my own. However, I have installed some container application on the same but during the work all of a sudden the SSH connection lost. Now, when I tried to get the connection again , it says- ssh -L 5901:localhost:5901 -I ssh-key.pem ubuntu@ec2-13-xxx-xxx-139.ap-south-1.compute.amazonaws.com connection timeout for port 22 Cause There could be multiple reasons of the same like, inbound rule changes for port 22, firewall turned on, Security group changes etc. In my case it was 'firewall turned on'. Solution So how should I go to turn off the firewall without native ssh connection which I do over terminal/putty?  The answer is through other was utilities like-  Browser based SSH...

AWS EC2 Ubuntu Instance VNC access

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In this post I'll write about how to connect to your EC2 Ubuntu linux instance via VNC Viewer app. Let's get started...... Kindly login to your AWS instance via private key through terminal/putty as shown below and follow the steps from 1 to 8 to access your Ubuntu (18.x in my case) GUI from your local machine- ssh -i your-aws-key.pem ubuntu@ec2-x-x-x-80.ap-south-1.compute.amazonaws.com Step-1 sudo apt update &&  sudo apt upgrade Step-2 sudo apt-get install ubuntu-desktop gnome-panel gnome-settings-daemon metacity nautilus gnome-terminal xfce4 vnc4server Step-3 vncserver Enter the password- xxxx Confirm Password- xxxx Step-4 vi ~/.vnc/xstartup Uncomment previous and use this one in xstartup file as shown below #!/bin/sh # Uncomment the following two lines for normal desktop: unset SESSION_MANAGER # exec /etc/X11/xinit/xinitrc unset DBUS_SESSION_BUS_ADDRESS startxfce4 & [ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup ...

Using external storage for enterprise grade deployments

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Hello everyone, In this post I am going to share one of my experience with respect to usage of SAN storage in enterprise grade deployment of Oracle SOA Suite. However, this concept  is common across any of the enterprise grade deployment. Once I got an opportunity to do the production grade deployment of oracle soa suite 12c where I was asked regarding the SAN (Storage Area network) storage usage. I wasn't aware about the different storages and their requirement. I did some research and came to know that storage is a-one of the most critical component in production deployment. This is why because we have different kind of data and different needs of accessing the same, e.g. we can have media files, image files, backup files, system files and the archived files etc. Below table gives the high level overview of different storage requirements and available options - S. No  Requirement to store  Recommended Storage 1  System files , boot volume, applicatio...