# website monitoring
How to Monitor WordPress Multisite
WordPress Multisite lets you run a network of sites from a single WordPress installation — commonly used by universities, media groups, franchise businesses, and agencies managing multiple brands. While the convenience of a shared codebase is appealing, Multisite introduces monitoring complexity: a single broken plugin, misconfigured domain mapping, or expired SSL certificate can take down individual sites while the rest of the network appears healthy.
How Multisite Changes Monitoring Requirements
A standard single WordPress install has one domain and one SSL certificate to watch. A Multisite network has:
- Multiple sub-sites — each potentially on its own domain (domain mapping) or subdomain
- Independent SSL certificates — each mapped domain needs its own certificate
- Shared infrastructure risk — a WordPress core update or plugin conflict can break the entire network simultaneously
- Network-level admin vs site-level health — the network admin being accessible doesn't mean individual sites are functioning
The key insight: you must monitor each site independently. A network health check at yournetwork.com only tells you the root domain is up. It says nothing about whether client-site-three.com mapped into your network is serving correctly.
What to Monitor
Each Mapped Domain
For subdomain installations:
Monitor: https://site1.yournetwork.com
Monitor: https://site2.yournetwork.com
Monitor: https://site3.yournetwork.com
For domain-mapped sites:
Monitor: https://client-one.com
Monitor: https://client-two.com
Monitor: https://client-three.com
Set a content check for something unique to each site (the site name, a headline) to confirm the correct site is loading rather than a generic WordPress error page or maintenance screen.
SSL Certificates — Every Domain
Domain-mapped Multisite sites each require their own SSL certificate. This is the most common source of silent failures: one site's Let's Encrypt certificate expires while all others are fine. Visitors to that specific site see a browser security warning, but there's no obvious signal to the network administrator.
SSL certificate monitoring with per-domain alerts catches this. For Multisite networks with wildcard subdomains, a wildcard SSL certificate reduces the number of certificates to manage.
Domain Expiry for Each Mapped Domain
If client sites are on domains you manage, monitor each domain's expiry independently. A single lapsed domain takes only that site offline — easy to miss without domain-level monitoring.
See domain expiry monitoring for configuration.
Network Admin Health Check
Monitor the WordPress health check endpoint at the network level:
Monitor: https://yournetwork.com/wp-json/
Expected status: 200
Content check: "WordPress"
This checks that WordPress is responding at the application layer, which requires PHP, the database, and the WordPress core to be functioning.
Plugin and Update Failure Detection
Multisite's shared codebase means a network-wide plugin update can simultaneously break all sites. After any plugin update or WordPress core update, run a quick sweep of all monitored site URLs and check for unexpected response codes (500 errors, blank pages, unexpected redirects).
Monitoring with content checks — verifying that a specific expected string appears in the response — catches the case where WordPress serves a 200 response on a broken white screen of death.
Alerting for Multisite Networks
Alert routing depends on who owns what:
- Network administrator — receives all network-level alerts
- Site owners (if applicable) — receive alerts for their specific site's URL
- Hosting provider contact — escalation path for server-level issues
Slack notifications work well for agencies managing Multisite on behalf of clients — route per-client alerts to per-client Slack channels.
Get Started
Domain Monitor monitors each site in your WordPress Multisite network individually — SSL, domain expiry, and uptime for every mapped domain. Create a free account.
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