Memcached is a high-performance, distributed memory object caching system that helps speed up web applications by caching data in memory to reduce the load on databases. In this tutorial, you will learn how to install and configure Memcached on Ubuntu 22.04, integrate it with PHP, and secure it with SASL authentication.

What You Can Do with Memcached:

• Cache Database Queries: Reduce database load by caching frequently accessed queries.
• Speed Up Web Applications: Improve the performance of dynamic websites by storing data in memory.
• Manage Sessions: Use Memcached to store and manage PHP session data.

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Step 1: Create a Cloud Instance

Before installing Memcached, you need to create a cloud instance where it will run. Here’s how to set up your instance:

Step 1.1: Click on “Create”

• From your hosting provider’s dashboard, click on the Create button and select Instances.

Step 1.2: Choose a Location

• Select the data center closest to your target audience (e.g., New York, London, Tokyo).

Step 1.3: Choose an Instance Plan and OS

• Choose an instance plan based on your needs (e.g., Standard, CPU-Optimized).
• Select Ubuntu 22.04 as the operating system.

Step 1.4: Create the Instance

• Fill in the necessary details, such as authentication (SSH keys or password), and choose a hostname. Click Create Instance.

Step 1.5: Find Your IP Address

• Once the instance is created, go to the Resources section to find the public IP address of your instance. You’ll need this to connect to the instance remotely.

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Step 2: Install Memcached

Install Memcached and its tools by running the following command:

apt install memcached libmemcached-tools -y

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Step 3: Start and Verify Memcached

Start Memcached and check its status to make sure it’s running:

systemctl start memcached
systemctl status memcached

Check the installed version of Memcached:

memcached -V

To confirm that Memcached is listening on the default port (11211), run:

ss -plunt | grep memcache

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Step 4: Install Apache, PHP, and PHP-Memcached

To integrate Memcached with PHP, install Apache, PHP, and the necessary PHP extensions:

apt install apache2 php libapache2-mod-php php-memcached php-cli -y

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Step 5: Test PHP and Memcached Integration

5.1: Create a PHP Info File

To verify PHP is working correctly, create a PHP file in /var/www/html:

nano /var/www/html/info.php

Add the following code:

<?php
   phpinfo();
?>

Save and close the file.

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Step 6: Restart Apache

After creating the PHP info page, restart Apache to ensure everything is working correctly:

systemctl restart apache2

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Step 7: Test Memcached with a PHP Script

Next, create a PHP test script to verify Memcached is functioning correctly:

nano /var/www/html/test.php

Add the following code to test Memcached:

<?php

try

{
$memcached = new Memcached();
$memcached->addServer("127.0.0.1", 11211); 
$response = $memcached->get("key_cache");

if($response==true) 
{
echo "Result coming from caching";
echo $response;
}

else

{
echo "Cache is not created yet, reload again to see changes";
$memcached->set("key_cache", "Hooray! Memcache is working now ...") ;
}
}
catch (exception $e)
{
echo $e->getMessage();
}
?>

Save and close the file.

7.1: Test in the Browser

Open your web browser and go to http://<your-server-ip>/test.php. If everything is set up correctly, you should see output indicating whether the result is being fetched from the cache.

Next, reload the page again. This time the page load from the cache memory as shown below:

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Step 8: Enable SASL Authentication for Memcached

8.1: Install SASL

To secure Memcached with authentication, install the SASL libraries:

apt install sasl2-bin

Create the necessary configuration directory:

mkdir -p /etc/sasl2

8.2: Configure SASL for Memcached

Create a SASL configuration file for Memcached:

nano /etc/sasl2/memcached.conf

Add the following lines to configure SASL:

log_level: 5
mech_list: plain
sasldb_path: /etc/sasl2/memcached-sasldb2

8.3: Set Up SASL Users

Create a user for Memcached:

saslpasswd2 -a memcached -c -f /etc/sasl2/memcached-sasldb2 user1

chown memcache:memcache /etc/sasl2/memcached-sasldb2

To check if Memcached is working properly, you can run the following command:

memcstat --servers="127.0.0.1"

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Step 9: Configure Memcached for SASL

Edit the Memcached configuration file to enable SASL and verbosity:

nano /etc/memcached.conf

Add the following lines:

-S
-vv

Restart Memcached for the changes to take effect:

systemctl restart memcached

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Step 10: Verify SASL Authentication

Check the logs to ensure SASL is working:

journalctl -u memcached | grep SASL

To verify that Memcached is using SASL, run:

memcstat --servers="127.0.0.1" --username=user1 --password=password

If successful, you should see statistics indicating that Memcached is functioning properly with SASL authentication enabled.

You have successfully installed and configured Memcached on Ubuntu 22.04, integrated it with PHP, and secured it with SASL authentication. Memcached is now ready to cache your web application’s data and enhance its performance.

To ensure high performance and security for your web applications, consider using Shape.Host’s Linux SSD VPS services. Shape.Host offers SSD-powered VPS solutions that provide optimal performance for caching systems like Memcached, ensuring your applications run smoothly.