In this tutorial, we'll explain how to install Memcached on Ubuntu 24.04.
Introduction
Memcached is a high-performance, distributed memory caching system designed to speed up dynamic web applications by reducing the database load. It achieves this by caching data and objects in RAM, thereby minimizing the need to repeatedly fetch data from the database or other slow storage layers.
Key Features
- In-Memory Storage: Memcached stores data in memory, ensuring rapid access times and significantly reducing latency.
- Distributed System: It can scale horizontally by adding more nodes, allowing for efficient load balancing and fault tolerance.
- Simple Protocol: Uses a straightforward, text-based protocol that is easy to implement and integrate with various programming languages.
- Data Types: Supports various data types, including strings, objects, and collections, allowing for flexible caching strategies.
- Event-Based Architecture: Employs an event-driven architecture that efficiently handles multiple simultaneous connections.
Prerequisites
- A Ubuntu 24.04 installed dedicated server or KVM VPS.
- Access the server using SSH as a non-root user with sudo privileges.
- Basic Linux command knowledge.
How to Install Memcached on Ubuntu
Step 1: Update Your System
First, ensure that your system is up-to-date by running the following commands:
sudo apt update
sudo apt upgrade -y
Step 2: Install Memcached
Install Memcached by running the following command:
sudo apt install memcached -y
Execute following command to verify Memcached installation:
memcached --version
Output:
memcached 1.6.24
This command should display the version of Memcached.
Step 3: Configure Memcached
The main configuration file for Memcached is located at /etc/memcached.conf. Open this file in your preferred text editor. For example:
sudo nano /etc/memcached.conf
In this file, you can set the memory size, default port, IP address, and other options. Here are some important configurations:
Memory Usage: Set the maximum amount of memory to use for object storage.
-m 64
Default Port: Set the port Memcached will listen on.
-p 11211
IP Address: Specify the IP address Memcached will listen on. By default, it listens on all available addresses.
-l 127.0.0.1
Uncomment the -c 1024 directive to limit the number of simultaneous Memcached connections. Replace 1024 with your desired number of connections.
-c 1024
After making the necessary changes, save and close the file.
To apply the changes, restart the Memcached service using the following command:
sudo systemctl restart memcached
To ensure Memcached is running properly, check its status with:
sudo systemctl status memcached
Step 4: Testing Memcached
You can use the telnet command to test if Memcached is working correctly. First, install telnet:
sudo apt install telnet -y
Then, connect to Memcached:
telnet 127.0.0.1 11211
You should see a prompt similar to this:
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
To test storing and retrieving data, use the following commands:
set mykey 0 900 4
data
This command sets a key mykey with the value data.
To retrieve the stored value:
get mykey
Output:
VALUE mykey 0 4
data
END
To exit telnet, type:
quit
Step 5: Connect to Memcached
Memcached is compatible with multiple application frameworks such as PHP, Perl, Python, Ruby, and Java. Follow the steps below to connect to Memcached and test the application using PHP.
Install PHP and the Memcached module.
sudo apt install php php-memcached -y
Create a new sample PHP script to connect to Memcached.
nano memcached.php
Add the following contents to the file.
<?php
$memcached = new Memcached();
$memcached->setOption(Memcached::OPT_BINARY_PROTOCOL, true);
$memcached->addServer('127.0.0.1', 11211);
$memcached->setSaslAuthData('example-user', 'strong-password');
// Set and retrieve a value to test the connection
$memcached->set('example', 'Greetings from Vultr!');
echo $memcached->get('example');
?>
Save and close the file.
The above PHP script connects to Memcached. A new key example with the value Greetings from HostMyCode is added to the Memcached memory and retrieved using the $memcached variable in the application.
Run the script using PHP to test the connection to Memcached.
php memcached.php
Output:
Greetings from HostMyCode!
Step 6: Securing Memcached
For security reasons, it's a good practice to bind Memcached to the localhost interface to prevent unauthorized access. Ensure the -l option in /etc/memcached.conf is set to 127.0.0.1:
-l 127.0.0.1
Additionally, consider setting up a firewall to restrict access to the Memcached port (11211).
Use ufw (Uncomplicated Firewall) to restrict access to the Memcached port (11211).
Enable ufw if it is not already enabled:
sudo ufw enable
Allow access only from the localhost:
sudo ufw allow from 127.0.0.1 to any port 11211
Verify the firewall rules:
sudo ufw status
Use SASL Authentication (Optional)
Memcached can be compiled with SASL support to enable authentication. If you need to secure your Memcached server with authentication, you can compile Memcached with SASL support. This is more complex and might not be necessary if you are already binding Memcached to localhost and using a firewall.
Enable Memcached on Boot. To ensure Memcached starts automatically on boot, enable the service:
sudo systemctl enable memcached
In this tutorial, we've successfully seen how to install Memcached on Ubuntu 24.04 server. You can integrate it with your applications to improve performance by caching data.
If you have any other questions or need further assistance, feel free to ask!
