Subdomain, Multilingual, Cache & Maintenance Mode

A subdomain like blog.yoursite.com or shop.yoursite.com is created through your hosting/domain provider's DNS settings, then pointed at either the same WordPress install (multisite) or a completely separate one.

Adding a subdomain and changing the logo URL

The site logo, set at Appearance → Customize → Site Identity, links to the homepage by default. To point it elsewhere (rare, but sometimes needed), a small snippet in your child theme's functions.php can override the default logo link filter.

Override the logo link with a filter (child theme functions.php)

<?php
add_filter( 'get_custom_logo', function ( $html ) {
    return str_replace( home_url( '/' ), 'https://yoursite.com/special-landing/', $html );
});

Making a multilingual site

The most common approach is a plugin like WPML or Polylang, which lets you write each post/page in multiple languages and shows a language switcher to visitors.

Real-life example: A multilingual plugin is like a restaurant menu printed in two languages back-to-back — same dishes (content), readable by more guests.

Polylang — free, good for straightforward multilingual sites
WPML — premium, more advanced features and support
Always assign a language to every post/page — untranslated content shows gaps

Clearing cache and enabling maintenance mode

If you use a caching plugin (WP Super Cache, W3 Total Cache, or your host's built-in cache), clear/purge the cache after major changes — otherwise visitors might see an old, stale version of your page.

Before big changes (a theme switch, major plugin update, or redesign), enable Maintenance Mode with a plugin like WP Maintenance Mode, showing visitors a friendly “back soon” page instead of a half-broken site.

Tip: Always test major changes on a staging copy first (see BlogVault in lesson 23) rather than relying solely on maintenance mode as your safety net.

Clear cache via WP-CLI (if a supported cache plugin is active)

wp cache flush

Archiving old posts and managing rights/roles

To archive outdated content without deleting it, either move it to Draft status, or use a plugin like PublishPress Future to auto-unpublish posts on a schedule.

Review Users → All Users periodically and remove or downgrade accounts that no longer need Administrator or Editor access — this is basic digital hygiene, similar to revoking a former employee's office keys.