To run our applications continuously, we have a few options:
If we experience a lot of traffic at specific hours of the day, or we expect to scale our application, it is better to go for a cloud service, where we can easily expand the server specs as we need.
Types of cloud services:
EC2 stands for Elastic Compute Cloud. It is a general-purpose computing resource with optimized computing performance, memory, storage, and networking. This can be automatically scaled up and down based on your application needs. Multiple operating systems are provided, but only the linux and windows instances (t2 or t3.micro) are available for the free tier.
The full list of EC2 instances can be found here.
A new IP will be allocated every time the instance is restarted. So to keep using a fixed IP address, we will use the Elastic IP.
On the left sidebar, click on Network & Security -> Elastic IPs.
Then click on ‘Associate Elastic IP Address’ and select your instance and private IP.
Important: Unassociated elastic IPs are billable. Make sure to associate it with your free tier instance to avoid getting billed.
Since I’m a mac user, I’ll explain how you can connect to your instance using the terminal. You can also find instructions on how to connect using ssh in your AWS console.
ssh -i keyfile.pem ec2-user@[ec2 ip address]
The default username is ec2-user.
If you don’t want to keep typing in the IP address, we can easily connect to a server using an alias. First, move your pem file to the following location, ~/.ssh/.
cp [current pem file path] ~/.ssh/
Then let’s create a config file. You can use any editor you like, but I’ll use nano.
nano ~/.ssh/config
Fill in the information.
# config
Host yourAlias
HostName yourHostName
User ec2-user
IdentityFile ~/.ssh/keyfile.pem
Set the name you want to use in the Host and input your EC2 instance hostname/IP for the HostName. Don’t forget to save.
You can now connect with the hostname you set.
ssh yourAlias
You’ll notice that when you connect to your instance, it will show your instance ip.
[ec2-user@ip-##-##-##-## ~]$
But this can be confusing when you have more than one servers. It’ll be easier to differentiate between servers if you name them.
It will depend on your instance type. So you can check here for more info.
For Amazon Linux 2, use the following command.
sudo hostnamectl set-hostname YourHostName
Then edit the file /etc/hosts using whatever editor you like.
sudo nano /etc/hosts
And add the following line:
127.0.0.1 YourHostName
Then reboot using sudo reboot.
Once you log in again, you’ll now see:
[ec2-user@YourHostName ~]$
If you’re going to set up a relational DB, you can use Amazon’s RDS (Relational Database Service). The reason we want to create our DB through this instance is that manually setting it up on our EC2 instance is not only time-consuming, but we won’t have the extra functionalities, like monitoring, that are provided by RDS.
These are the first few things to set up after creating your RDS instance:
We can set this up in the parameter group. On the left sidebar, click on “Parameter groups” and create a new group. Let’s edit the parameters we mentioned above.
Look for the time_zone parameter and set it to your timezone.
Type in character_set and set all the parameters that show up to utf8mb44, which is the charset used if you want to support emojis.
The current utf8 is an alias for utf8mb3, which encodes Unicode characters using 1-3 bytes per character. utf8mb4, on the other hand, uses 1-4 bytes per character.
UTF-8 encoding the same as utf8mb3 but which stores supplementary characters in four bytes.
Search for collation and set all the parameters to utf8mb4_general_ci. What is collation?
In database systems, Collation specifies how data is sorted and compared in a database. Collation provides the sorting rules, case, and accent sensitivity properties for the data in the database.
Once we save all the parameters, we need to change the DB settings so that it uses this newly created parameter group. Click on ‘Databases’ on the left sidebar and click on ‘Modify’, then update the parameter group accordingly. Reboot the DB.
To access the DB from your local PC, you must configure the security group. Also, make sure you make your DB as ‘Publicly Accessible’ when creating the RDS instance.
Add the following inbound rules:
Then connect to the DB using the ‘Endpoint’ shown on your RDS console as the hostname. If you don’t remember the username, you can find it under the ‘Configuration’ tab, under ‘Master username’.
Once you connect to your DB, you will see that some of the parameters (character_set_database, collation_connection) set from the parameter group haven’t been properly set. You can check by running the following command:
use YourDBName; /* You can find it under the 'DBName' in your AWS console */
show variables like 'c%';
You’ll see that the parameters mentioned above will be set to latin or something similar. Let’s update this to utf8mb4.
ALTER DATABASE YourDBName
CHARACTER SET = 'utf8mb4'
COLLATE = 'utf8mb4_general_ci';
Check and see if the timezone has been properly set.
select @@time_zone, now();
Let’s make sure we can access the RDS instance from the EC2 instance.
Connect to your EC2 instance and install MySQL.
sudo yum install mysql
Now connect to your DB.
mysql -u [YourUserName] -p -h [YourDBEndpoint]
You should be able to connect to it. If you’re not able to, double-check your security group and see if your inbound rules have been set properly.
AMIs are image containers that contain all the necessary components to launch the instances. ↩
VPCs are virtual private networks, virtual versions of a physical network within the larger network. ↩
This is automatically calculated based on the instance, but we can also manually set it through the max_connections parameter. Check here for more info. ↩
Check out this stackoverflow post for more info. ↩