If you haven’t got it yet, anyone running more than one Mac should be using the macOS Content Caching server to minimise the quantity of downloads for macOS updates and other content which their Macs consume. I’ve already provided an overview of how to turn it on and configure a basic service. This article goes deeper to discover more about how it works, how you can monitor its performance and effectiveness, and how to troubleshoot it.
When you have a Content Caching server running on your network, other Macs connect to it when downloading Apple-provided updates and content, including files in iCloud, as set in its options in the Sharing pane. Clients, including Macs, iOS and iPadOS devices, need no configuration: once the service is turned on, the next time that they start up, they’ll automatically connect to it, and from then on, whenever they download cached content, it will be obtained from that server.
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