WordPress Multisite Server Setup

Technically it can, but shared hosting environments have significant limitations for multisite. Most shared hosts do not support wildcard DNS entries, which are required for subdomain-based multisite. Wildcard SSL configuration via DNS challenge is often unavailable. Resource limits are shared across all sites in the network, so a traffic spike on one site affects the others. And you have no control over PHP-FPM worker counts, database connection limits, or caching configuration.

For anything beyond a small hobby multisite, a VPS with dedicated resources and proper server configuration is the right foundation.

Subdomain multisite serves each network site from a subdomain of the main domain, for example site1.yourdomain.com and site2.yourdomain.com. This requires wildcard DNS and wildcard SSL at the server level.

Subdirectory multisite serves each network site from a path under the main domain, for example yourdomain.com/site1 and yourdomain.com/site2. This does not require wildcard DNS or SSL but has some limitations around certain plugins and URL structures.

The right choice depends on your use case. We discuss this during initial scoping and set up the server configuration accordingly.

A wildcard SSL certificate covers a domain and all of its subdomains. For subdomain multisite, a wildcard certificate means that when a new site is added to the network, it automatically gets HTTPS coverage without requiring a separate certificate to be issued.

Let's Encrypt issues free wildcard certificates, but the verification process requires DNS challenge rather than the standard HTTP file challenge. This means either configuring API access to your DNS provider so Let's Encrypt can automatically add the required DNS records, or handling manual verification. We configure automatic DNS challenge renewal as part of the multisite server setup.

Domain mapping allows a site within your multisite network to be accessed at its own domain, such as client-site.co.uk, rather than a subdomain like client.yourdomain.com. It requires both DNS configuration by the domain owner and server-level configuration to accept and route requests for the custom domain to the correct multisite installation.

We configure Nginx or OLS server blocks to handle domain-mapped sites correctly, and set up WordPress multisite for domain mapping using the WordPress sunrise.php mechanism or a plugin like WP Multisite Domain Mapping.

Caching for multisite needs to create separate cache stores per site rather than a shared cache that could serve the wrong site's content to the wrong visitor. We configure page caching, whether via Nginx FastCGI cache, LiteSpeed Cache, or a compatible WordPress plugin, to partition by site correctly.

Object caching via Redis also needs to be configured with site-aware key prefixes so that each site's object cache does not collide with others in the network.

Yes. Multisite migrations are more complex than single site migrations because of the shared database structure, upload directory organisation, and potential domain mapping configurations that need to be preserved. We handle complete multisite migrations including database export and import, URL updates across all network sites, upload directory migration, and DNS cutover.

Cost depends on the network type, subdomain or subdirectory, whether domain mapping is required, the number of existing sites to migrate, and the VPS provider. We provide a fixed-price quote after understanding your multisite requirements.

A fresh WordPress multisite server setup on a new VPS typically takes 2 to 3 days. Migrations of existing multisite networks take longer depending on the number of sites, generally 3 to 5 days.