XML-RPC

XML-RPC is enabled by default since WordPress version 3.5 and allows communication between WordPress and other systems. If XML-RPC is disabled, any services relying on it will no longer work as expected.

Most of Jetpack’s features rely on the XML-RPC connection, and disabling XML-RPC would negatively affect:

• Uptime monitoring: Jetpack provides uptime monitoring for launched sites as part of VIP’s infrastructure alerting.
• Jetpack sync: Jetpack sync features—including Jetpack Stats, Jetpack Related Posts, and Jetpack Activity Log—rely on a working XML-RPC connection.
• Jetpack Search: Jetpack’s Elasticsearch solution increases search result speed and relevancy. If XML-RPC is disabled, Elasticsearch will not be reachable. Slow queries that would usually be offloaded to Elasticsearch will instead go directly to MySQL, which can cause performance issues.

VIP has multiple WordPress-specific security protections in place to protect against unauthorized access and abuse of the XML-RPC endpoint.