Cloud Native WordPress on Alibaba Cloud

Quick start with Wordpress on Alibaba Cloud with cloud native features such as high availability, auto-scaling, etc.

You can access the tutorial artifact including deployment script (Terraform), related source code, sample data and instruction guidance from the github project: https://github.com/alibabacloud-howto/solution-cloud-native-web-hosting

More tutorial around Alibaba Cloud Database, please refer to: https://github.com/alibabacloud-howto/database

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Project URL

https://github.com/alibabacloud-howto/solution-cloud-native-web-hosting

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Architecture Overview

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Index

• Deployment
  • Terraform
• Run Demo
  • Step 1: Install Apache HTTP Server and PHP on ECS
  • Step 2: Install and configure Wordpress on ECS
  • Step 3: Configure Redis caching
  • Step 4 (Optional): Make custom ECS image for auto scaling
  • Step 5 (Optional): Setup Auto Scaling (ESS) for ECS auto scaling
  • Step 6 (Optional): Simulate fluctuating traffic to trigger auto scaling

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Deployment

Terraform

If you are the 1st time to use Terraform, please refer to https://github.com/alibabacloud-howto/terraform-templates to learn how to install and use the Terraform on different operating systems.

Use terraform to provision VPC, SLB, EIP, ESS, ECS, Redis and PolarDB instances that used in this solution against this .tf file: https://github.com/alibabacloud-howto/solution-cloud-native-web-hosting/blob/main/deployment/terraform/main.tf

For more information about how to use Terraform, please refer to this tutorial: https://www.youtube.com/watch?v=zDDFQ9C9XP8

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Run Demo

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Step 1: Install Apache HTTP Server and PHP on ECS

• Logon to ECS via SSH, use the account root/N1cetest, the password has been predefined in Terraform script for this tutorial. If you changed the password, please use the correct password accordingly.

ssh root@<EIP_ECS>

There are 2 ways to get the EIP applied for the ECS in Terraform:

• Go to ECS web console:

• In the command line, under the same folder of the terraform script file main.tf, open "terraform.tfstate":

If you met this error when ssh to ECS, please go to /Users/xxx/.ssh/known_hosts, VI to edit the file and remove the whole line with the EIP of the target ECS at the very beginning. After that, please SSH to log on again.

• Run the following command to install required utilities on the instance:

yum install -y sysbench unzip zip dstat

• Zip: a utility commonly used for compressing files and folders

• Unzip: a utility used for decompressing files and folders.

• Sysbench: a benchmarking tool used for system performance testing.

• Dstat: a monitoring tool that provides statistics about system performance.

• Install Apache HTTP Server

Run the following command to install the Apache HTTP server:

yum -y install httpd

• Install PHP

List available versions of PHP:

dnf module list php

Most likely php 7.4 is included, so run the following commands to enable PHP 7.4 (Please make sure the PHP version is new to catch up the requirement of the Wordpress, otherwise Wordpress installation would fail possibly):

dnf module reset php
dnf module enable php:7.4 -y
dnf install -y php php-opcache php-gd php-curl php-mysqlnd
dnf install -y php-bcmath php-mbstring php-xmlwriter php-xmlreader php-cli php-ldap php-zip php-fileinfo

Then restart Apache HTTP Server:

service httpd restart

Configure to auto start httpd service when ECS restarting:

chmod +x /etc/rc.d/rc.local
vim /etc/rc.d/rc.local

Add the line at the end and save:

service httpd restart

Create a PHP file to verify the PHP is working:

vim /var/www/html/info.php

Then input the following content in this info.php file, then save and exit.

<?php
phpinfo();
?>

Then open the following URL in a Web browser (Note: Replace the <ECS_EIP> placeholder with the Elastic IP address of the ECS instance that you obtained previously):

http://<ECS_EIP>/info.php

If the following page appears, PHP is installed successfully.

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Step 2: Install and configure Wordpress on ECS

Create a folder, download the WordPress package to this folder, and extract the package. To do this, run the following commands in sequence:

mkdir -p /opt/WP  
cd /opt/WP 
wget https://wordpress.org/latest.tar.gz 
tar -xzvf latest.tar.gz 

Run the following commands in sequence to configure WordPress to access ApsaraDB for PolarDB:

cd /opt/WP/wordpress/ 
cp wp-config-sample.php wp-config.php 
vim wp-config.php 

Complete the database configurations as follows:

Setting	Value & description
DB_NAME	The name of the ApsaraDB for PolarDB database that you created. In this tutorial, we use "wpdb", which is predefined in resource "alicloud_polardb_database" within Terraform script https://github.com/alibabacloud-howto/solution-cloud-native-web-hosting/blob/main/deployment/terraform/main.tf.
DB_USER	The user name of the database account you created. In this lab, we use "test_polardb" as predefined within Terraform script.
DB_PASSWORD	The password of the database account you created within Terraform script. In this lab, we use "N1cetest" as predefined within Terraform script.
DB_HOST	The VPC-facing endpoint of the ApsaraDB for PolarDB cluster that you obtained previously. Do not include the port number. Please use the Cluster endpoint of PolarDB.

Endpoint on PolarDB web console:

Run the following commands in sequence to copy the wordpress folder to the /var/www/html/ path:

cd /var/www/html 
cp -rf /opt/WP/wordpress/* /var/www/html/ 

Open the following URL in a Web browser to initialize WordPress:

http://<ECS_EIP>

Note: Replace the <ECS_EIP> placeholder with the Elastic IP address of the ECS instance that you obtained previously.

Then complete the settings and click "Install WordPress".

Then the following page shows, which means the installation is success.

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Step 3: Configure Redis caching

Run the following commands in sequence to download the Redis object cache plugin and unzip the plugin package:

cd /opt/WP
wget https://downloads.wordpress.org/plugin/redis-cache.2.0.18.zip 
unzip redis-cache.2.0.18.zip 

Run the following commands in sequence to copy the redis-cache folder to the /var/www/html/wp-content/plugins/ path and configure WordPress to access ApsaraDB for Redis:

cp -rf redis-cache /var/www/html/wp-content/plugins/ 
vim /var/www/html/wp-config.php

Complete the settings as follows:

Setting	Value & Description
WP_REDIS_HOST	The internal endpoint of the ApsaraDB for Redis instance that you obtained previously. Such as r-xxxxx.redis.singapore.rds.aliyuncs.com
WP_REDIS_PORT	The port number.
WP_REDIS_PASSWORD	The password for connecting to the instance.

// Redis settings
define( 'WP_REDIS_HOST', '<Redis URL>' );
define( 'WP_REDIS_CLIENT', 'predis' );
define( 'WP_REDIS_PORT', '6379' );
define( 'WP_REDIS_DATABASE', '0');
define( 'WP_REDIS_PASSWORD', 'test_redis:N1cetest' );

Please MAKE SURE this Redis setting block is set at the first settings block of the wp-config.php file as shown in the image above.

Run the following command to copy the object-cache configuration file to the /var/www/html/wp-content/ path:

cp /var/www/html/wp-content/plugins/redis-cache/includes/object-cache.php /var/www/html/wp-content/ 

Log on to WordPress to enable Redis object cache.

In the left-side navigation pane, click Plugins. Find the Redis Object Cache plugin and click Activate.
After the plugin is activated, click Settings.

Verify that the plugin status is Connected. Click Flush Cache to synchronize cache data to the ApsaraDB for Redis instance.

Now, your cloud native Wordpress has been setup successfully. You can visit it via SLB EIP:

http://<SLB_EIP>/

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Step 4 (Optional): Make custom ECS image for auto scaling

Follow these steps to create an image from the ECS instance:

• Log on to the ECS console. Click "Images" in the left-side navigation pane, then Click "Create Now".

• Select "Instance", select the target ECS that with WordPress installed previously, enter a name and a description for the image, and then click "Create". In this lab, the image name is wp_image.

• Wait until the image creation progress becomes 100%.

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Step 5 (Optional): Setup Auto Scaling (ESS) for ECS auto scaling

Follow these steps to enable Alibaba Cloud Auto Scaling:

• Log on to the Auto Scaling console. Click "Create Scaling Group".

• Select "Create from Scratch" and click "Start Creation".

• In the "Create Scaling Group" section, complete the settings as follows:

Setting	Value & Description
Scaling Group Name	wp_auto_scaling
Instance Configuration Source	Create from Scratch
Instance Removing Policy	For "Filter First", select "Earliest Instance Created Using Scaling Configuration". For "Then Remove from Results", select "Most Recent Created Instance".
Minimum Number of Instances	2
Maximum Number of Instances	5
Default Cooldown Time (Seconds)	300
Network Type	VPC
Multi-zone Scaling Policy	Balanced Distribution Policy
Instance Reclaim Mode	Release Mode
VPC	Select the VPC created before by Terraform
Select VSwitch	Select all the VSwitches created before by Terraform. There are 2 VSW.
Associate SLB Instance	Select the SLB created before by Terraform.

• Click "OK" to finish the creation of the scaling group.

• Click "Add Scaling Configuration".

• Complete the settings as following:

Setting	Value & description
Billing Method	Pay-As-You-Go
Instance Type	ecs.g5.xlarge and ecs.c5.xlarge, or you can select other ECS class to the optional list for auto scaling
Image	Click "Custom Image" and select the "wp_image" image that you created previously.
Storage	Select "Ultra Disk" and "40 GiB" for the system disk. Click "Add Disk" and select "Ultra Disk" and "100 GiB" for the data disk.
Security Group	Select the security group that you created previously.

• In the "Logon Credentials" section, select “Inherit Password from Image”. In the "Instance Name" field, enter a name for the instance. In this lab, we use WP. Then click "Preview".

• In the "Scaling Configuration Name" field, enter a name for the scaling configuration. In this lab, we use wp_as_group. Then click "Create".

• Wait until the success message appears. Click "Enable Configuration" and "OK" to enable the scaling configuration.

• Click the "Instances", "Manually Added" tab and then click "Add Existing Instances".

• Add the ECS that you installed WordPress previously.

• Follow the following steps to create 2 scaling rules (ADD and DROP).

Setting	Value & description
Name	ADD1
Rule Type	Simple Scaling Rule
Operation	Add 1 Instances

Setting	Value & description
Name	DROP1
Rule Type	Simple Scaling Rule
Operation	Remove 1 Instances

• Follow the following steps to create 2 event triggered tasks mapping to the scaling rules respectively (CPU busy to ADD, CPU idle to DROP).

Setting	Value & description
Task Name	cpu_busy
Resource Monitored	Select the "wp_auto_scaling" scaling group you created previously.
Monitoring Type	System Monitoring
Monitoring Metric	(ECS) CPU Utilization
Condition	Average >= Threshold 70%
Triggered Rule	Select the "ADD1" rule you created previously.

Setting	Value & description
Task Name	cpu_idle
Resource Monitored	Select the "wp_auto_scaling" scaling group you created previously.
Monitoring Type	System Monitoring
Monitoring Metric	(ECS) CPU Utilization
Condition	Average <= Threshold 50%
Triggered Rule	Select the "DROP1" rule you created previously.

• Verify that the statuses of new scaling tasks are both Normal.

• After for a while (since the default setting is "triggered after 3 times for each 1 minute reference period", so please be patient to wait at least 3 minutes), verify that the statuses of SLB and the backend servers are Normal. 1 new ECS server were scaled out by auto scaling service and attached to SLB instance for load balancing.

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Step 6 (Optional): Simulate fluctuating traffic to trigger auto scaling

• Modify the auto scaling event-triggered task "cpu_busy" with the condition to "Maximum >= 70%"

• Log on to the ECS with EIP bound before, and run the sysbench to simulate the high CPU workload

sysbench cpu --cpu-max-prime=4000000 --threads=4 --time=1000 run

• After for a while (since the default setting is "triggered after 3 times for each 1 minute reference period", so please be patient to wait at least 3 minutes), verify the auto scaling event triggered with a new instance added

• After for a while, verify the SLB instance is attached with 3 ECS instances.

• Then you can "ctrl + C" to stop the sysbench workload, and verify the ECS count backs to 2 following the "cpu_idle" auto scaling rule after the rule event is triggered.