In this blog, we are going to see how to increase or decrease the size of the static partition in Linux without compromising any data loss and how to do that in Online mode without unmounting.

I already explained the basic concepts of partition in very detail in my previous blog. You can refer to that blog by clicking here.

In this practical, the Oracle VirtualBox is used for hosting the Redhat Enterprise Linux (RHEL8) Virtual Machine (VM).

The first step is to attach one hard disk. So, I attached one virtual hard disk with the size of 40GiB. That disk is named “/dev/sdc”. You can check the disk name and all other disks present in your VM by running the following command.

fdisk -l

Then, we have to do partition by using “fdisk” command.

fdisk /dev/sdc

Then, enter “n” in order to create a new partition. Then enter the partition number and specify the number of sectors or GiB. Here, we entered 20 GiB in order to utilize that much storage unless we do partition, we can’t utilize any storage.

We had created one partition named as “/dev/sdc1”. Next step is to format the partition. Here, we used Ext4 filesystem(format) to create an inode table.

Next step is to create one directory using “mkdir” command and mount that partition in that directory since we can’t directly use the hardware device no matter it is either real or virtual.

One file should be created inside that directory in order to check the data loss after Live scaling of static partition.

Ok, now the size of the static partition is 20 GiB, we are going to do scaling up to 30GiB without unmounting the partition. For this, again we have to run the following command.

fdisk /dev/sdc

Then delete the partition. Don’t bother about the data, it won’t lose.

Then enter “n” to create the new partition and specify your desired size. Here, I like to scale up to 30GiB. And then one warning will come and it says that “Partition 1 contains an ext4 signature” and ask us what to do with that either remove the signature or retain.

If you don’t want to lose the data, then enter “N”. Then enter “w” to save the partition. you can verify your partition size by running “fdisk -l” command in terminal. Finally, you increased the size of static partition.

First part is done. Then next step is to format the partition in order to create the file system. But this time, we will not use “mkfs” command, since it will delete all the data. We don’t need it. We have to do format without comprising the data. For that we have to run the following command.

resize2fs  /dev/sdc1

Finally, we done format without comprising the data. We can check this by going inside that mount point and check whether the data is here or not.

Yes, data is here. It is not lost even though we created new partition and formatted the partition.

Live Linux Static Partition scaling without any data loss

In this blog, we are going to see how to increase or decrease the size of the static partition in Linux without compromising any data loss and done in Online mode.

I already explained the basic concepts of partition in very detail in my previous blog. You can refer to that blog by clicking here.

In this practical, the Oracle VirtualBox is used for hosting the Redhat Enterprise Linux (RHEL8) Virtual Machine (VM).

The first step is to attach one hard disk. So, I attached one virtual hard disk with the size of 40GiB. That disk is named “/dev/sdc”. You can check the disk name and all other disks present in your VM by running the following command.

fdisk -l

Then, we have to do partition by using “fdisk” command.

fdisk /dev/sdc

Then, enter “n” in order to create a new partition. Then enter the partition number and specify the number of sectors or GiB. Here, we entered 20 GiB in order to utilize that much storage unless we do partition, we can’t utilize any storage.

We had created one partition named as “/dev/sdc1”. Next step is to format the partition. Here, we used Ext4 filesystem(format) to create an inode table.

Next step is to create one directory using “mkdir” command and mount that partition in that directory since we can’t directly use the hardware device no matter it is either real or virtual.

One file should be created inside that directory in order to check the data loss after Live scaling of static partition.

Ok, now the size of the static partition is 20 GiB, we are going to do scaling up to 30GiB without unmounting the partition. For this, again we have to run the following command.

fdisk /dev/sdc

Then delete the partition. Don’t bother about the data, it won’t lose.

Then enter “n” to create the new partition and specify your desired size. Here, I like to scale up to 30GiB. And then one warning will come and it says that “Partition 1 contains an ext4 signature” and ask us what to do with that either remove the signature or retain.

If you don’t want to lose the data, then enter “N”. Then enter “w” to save the partition. you can verify your partition size by running “fdisk -l” command in terminal. Finally, you increased the size of static partition.

First part is done. Then next step is to format the partition in order to create the file system. But this time, we will not use “mkfs” command, since it will delete all the data. We don’t need it. We have to do format without comprising the data. For that we have to run the following command.

resize2fs  /dev/sdc1

Finally, we done format without comprising the data. We can check this by going inside that mount point and check whether the data is here or not.

Yes, data is here. It is not lost even though we created new partition and formatted the partition.

Reduce the size of the Static Partition

You can also reduce the Static Partition size. For this, you have to follow the below steps.

• Unmount
• Cleaning bad sectors
• Format
• Mount

First step is to unmount your mount point since it is online, somebody will using it.

umount /partition1

Then we have to clean the bad sectors by running the following command

e2fsck -f /dev/sdc1

Then we have to format the size you want. Here we want only 20 GiB and we will reduce the remaining 10 GiB space. This is done by running following command.

resize2fs /dev/sdc1 20G

Then we have to mount the partition.

Finally, we reduced the static partition size.

Above figure shows that Data is also not lost during scaling down.

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Thank you all for your reads. Stay tuned for my next article, because it is Endless.

Hosting your own WordPress website is interesting right!! Ok, come on let’s do it!!

We are going to do this practical from Scratch. From the Creation of our Own VPC, Subnets, Internet Gateway, Route tables to Deployment of WordPress.

Here, we are going to use Amazon Web Service’s RDS service for hosting our own WordPress site. Before that, let’s take a look at a basic introduction to RDS service.

Amazon Relational Database Service is a distributed relational database service by Amazon Web Services (AWS). It is a web service running in the cloud designed to simplify the setup, operation, and scaling of a relational database for use in applications. Administration processes like patching the database software, backing up databases and enabling point-in-time recovery are managed automatically.

Features of AWS RDS

• Lower administrative burden. Easy to use
• Performance. General Purpose (SSD) Storage
• Scalability. Push-button compute scaling
• Availability and durability. Automated backups
• Security. Encryption at rest and in transit
• Manageability. Monitoring and metrics
• Cost-effectiveness. Pay only for what you use

Ok, let’s jump onto the practical part!!

We will do this practical from scratch. Since it will be big, so we divided this into 5 small parts namely

• Creating a MySQL database with RDS
• Creating an EC2 instance
• Configuring your RDS database
• Configuring WordPress on EC2
• Deployment of WordPress website

Creating a MySQL database with RDS

Before that, we have to do two pre-works namely the Creation of Virtual Private Cloud(VPC), Subnets and Security groups. These are more important because in order to have a reliable connection between WordPress and MySQL database, they should be located in the same VPC and should have the same Security Group.

Since Instances are launched on Subnets only, Moreover RDS will launch your MySQL database in EC2 instance only that we cannot able to see since it is fully managed by AWS.

We are going to create our own VPC. For that, we have to specify IP range and CIDR. We specified IP and CIDR as 192.168.0.0/16.

What is CIDR?. I explained this in my previous blog in very detail. You can refer here.

Lets come to the point. After specifying the IP range and CIDR, enter your VPC name.

Now, VPC is successfully created with our specified details.

Next step is to launch the subnet in the above VPC.

For Creating Subnets, you have to specify which VPC the lab should launch. We already have our own VPC named “myvpc123”.

And then we have to specify the range of Subnet IP and CIDR. Please note that the Subnet range should come under VPC range, it should not exceed VPC range.

For achieving the property of High Availability, We have to launch minimum two subnets, so that Amazon RDS will launch its database in two subnets, if one subnet collapsed means, it won’t cause any trouble.

Now, two Subnets with their specified range of IPs and CIDR are launched successfully inside our own VPC and they are available.

Next step is to create a security group in order to secure the WordPress and MySQL databases. Note that both should have the same Security Group or else it won’t connect.

For creating a Security Group, we have to specify which VPC it should be launched and adding a Description is mandatory.

Then we have to specify inbound rules, for making this practical simple, we are allowing all traffic to access our instance.

Now, the Security Group is successfully created with our specified details.

Now let’s jump into part 1 which is about Creating a MySQL database with RDS.

Select Create database, then select Standard create and specify the database type.

Then you have to specify the Version. Version plays a major role in MySQL when integrating with WordPress, so select the compactible version or else it will cause serious trouble at the end. Then select the template, here we are using Free-tier since it won’t be chargeable.

Then you have to specify the credentials such as Database Instance name, Master username and Master password.

Most important part is a selection of VPC, you should select the same VPC where you will launch your EC2 instance for your WordPress and we can’t modify the VPC once the database is created. Then select the Public access as No for providing more security to our database. Now, the people outside of your VPC can’t connect to your database.

Then you have to specify the security group for your database. Note that the Security Group for your database and WordPress should be the same or else it will cause serious trouble.

Note that Security Groups is created per VPC. After selecting Security Group, then click Ok to create the RDS database.

Creating an EC2 instance

Before creating an instance, there should be two things you configured namely Internet Gateway and Route tables. It is used for providing outside internet connectivity to an instance launched in the subnet.

Internet Gateway is created per VPC. First, we have to create one new Internet Gateway with the specified details.

Then you have to attach Internet Gateway to the VPC

Next step is to create Routing tables. Note that Route table is created per Subnet.

We have to specify which VPC in which your subnet is available to attach routing table with it, specify Name and click create to create the route table.

Then click Edit route to edit the route details namely destination and target. Enter destination as 0.0.0.0/0 for accessing any IP anywhere on the Internet and target is your Internet Gateway.

After entering the details, click Save routes.

We created a Route table, then we have to attach that table to your Subnet. For that click Edit route table association and select your subnet where you want to attach the route table with it.

Now, lets jump into the task of creating an EC2 instance.

First, you have to choose the AMI image in which you used for creating an EC2 instance, here I selected Amazon Linux 2 AMI for that.

Then you have to select Instance type, here I selected t2.micro since it comes under free tier.

Then you have to specify the VPC, Subnet for your instance and you have to enable Auto-assign Public IP in order to get your Public IP to your instance.

Then you have to add storage for your instance. It is optional only.

Then you have to specify the tags which will be more useful especially for automation.

Then you have to select the Security Group for your instance. It should be the same as your database have.

And click Review and Launch. Then you have to add Keypair to launch your EC2 instance. If you didn’t have Keypair means, you can create at that time.

Configuring your RDS database

At this point, you have created an RDS database and an EC2 instance. Now, we will configure the RDS database to allow access to specific entities.

You have to run the below command in your EC2 instance in order to establish the connection with your database.

export MYSQL_HOST=<your-endpoint>

You can find your endpoint by clicking database in the RDS dashboard. Then you have to run the following command.

mysql --user=<user> --password=<password> dbname

This output shows the database is successfully connected to an EC2 instance.

In the MySQL command terminal, you have to run the following commands in order to get all privileges to your account.

CREATE USER 'vishnu' IDENTIFIED BY 'vishnupassword';
GRANT ALL PRIVILEGES ON dbname.* TO vishnu;
FLUSH PRIVILEGES;
Exit

Configuring WordPress on EC2

For Configuring WordPress on EC2 instance, the first step is to configure the webserver, here I am using Apache webserver. For that, you have to run the following commands.

sudo yum install -y httpd

sudo service httpd start

Next step would be download the WordPress application from the internet by using wget command. Run the following code to download the WordPress application.

wget https://wordpress.org/latest.tar.gz
tar -xzf latest.tar.gz

Then we have to do some configuration, for this follow the below steps.

cd wordpress
cp wp-config-sample.php wp-config.php
cd wp-config.php

Go inside the wp-config.php file and enter your credentials (including your password too)

Then, Goto this link and copy all and paste it to replace the existing lines of code.

Next step is to deploy the WordPress application. For that, you have to run the following commands in order to solve the dependencies and deploy WordPress in the webserver.

sudo amazon-linux-extras install -y lamp-mariadb10.2-php7.2 php7.2

sudo cp -r wordpress/* /var/www/html/

sudo service httpd restart

That’s it. You have a live, publicly-accessible WordPress installation using a fully-managed MySQL database on Amazon RDS.

Then if you enter your WordPress instance IP in your browser, you will land your WordPress home page.

After you filled in your credentials, you will get your own homepage.

That’s it. You launched your own application in your own instance and your database is managed by AWS RDS service.

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Thank you all for your reads. Stay tuned for my next article.