Redis and Memcached Setup

Redis and Memcached keep frequently used data in memory, so your application can skip repeated database queries. Neither is available on Domain India shared hosting: to use them, you install and run them yourself on a VPS. This guide explains what to use on shared hosting instead, and how to set up Redis or Memcached safely on your own server.

1. Redis vs Memcached

For a new PHP or WordPress site, Redis (or Valkey, its open-source fork) is the usual choice.

2. What you can use on Domain India shared hosting

Shared hosting has no Redis or Memcached server, and the PHP extensions for them are not loaded, so enabling them from the panel is not possible. You still get useful caching:

• OPcache keeps compiled PHP in memory. It is enabled on our cPanel servers, and on our DirectAdmin servers for every PHP version except PHP 8.3. See PHP OPcache guide.
• Page caching plugins for WordPress, such as WP Super Cache or W3 Total Cache with disk caching, serve stored pages without running PHP for each visitor.
• The cPanel caching proxy: our cPanel servers run nginx in front of Apache, and it can keep serving a stored copy of a page for up to 120 minutes. Add ?t=1 to a URL to check a change.
• Laravel and other frameworks: use the database or file cache driver.

If the site is still slow, work through My website is slow before you move to a bigger setup.

3. Install Redis on your VPS

A Domain India VPS is self-managed: you have root access and look after the software yourself.

# Ubuntu / Debian
sudo apt update
sudo apt install -y redis-server
sudo systemctl enable --now redis-server

# AlmaLinux / Rocky 9
sudo dnf install -y redis
sudo systemctl enable --now redis

# AlmaLinux / Rocky 10 ship Valkey, a compatible fork
sudo dnf install -y valkey
sudo systemctl enable --now valkey

Check that it answers:

redis-cli ping      # or: valkey-cli ping
# PONG

4. Secure and size Redis

Edit the config file: /etc/redis/redis.conf on Ubuntu and AlmaLinux 9, or /etc/valkey/valkey.conf for Valkey.

# Listen on this server only
bind 127.0.0.1 -::1
protected-mode yes

# Require a password
requirepass your-strong-password

# Cap memory and evict the least recently used keys when full
maxmemory 256mb
maxmemory-policy allkeys-lru

Restart the service after any change. Never open port 6379 in your firewall: an exposed Redis is one of the most common ways servers get taken over.

5. Install Memcached on your VPS (if you need it)

# Ubuntu / Debian
sudo apt install -y memcached
# AlmaLinux / Rocky
sudo dnf install -y memcached
sudo systemctl enable --now memcached

Make sure it listens on 127.0.0.1 only and has UDP disabled (-l 127.0.0.1 -U 0 in /etc/memcached.conf on Ubuntu, or OPTIONS in /etc/sysconfig/memcached on AlmaLinux). Memcached has no password by default, so it must never be reachable from the internet.

For PHP, install the matching extension from your OS packages (for example php-redis or php-memcached on Ubuntu), or with PECL. Note that memcached and memcache are different PHP extensions; most applications want memcached.

6. Connect WordPress and Laravel

For Laravel, set CACHE_STORE=redis (Laravel 11 and later; older versions use CACHE_DRIVER) and the REDIS_* values in .env. Tags, locks and stampede prevention are covered in Laravel + Redis cache.

7. Monitor and troubleshoot

• Hit rate: redis-cli INFO stats shows keyspace_hits and keyspace_misses. For Memcached, send stats to port 11211 and compare get_hits with get_misses.
• Memory: redis-cli INFO memory. If memory keeps growing, set maxmemory and an eviction policy.
• Cannot connect: check the service with systemctl status redis (or redis-server, valkey), the port, and that the password matches in the config and your app.
• WordPress cache not working: check that wp-content/object-cache.php exists and that only one caching plugin handles the object cache.

For more on caching layers, see Server-side caching.

Ready to run Redis? Choose a Domain India VPS. For help with caching on your hosting account, open a support ticket.