--- title: "*.icloud.com: what it is and what breaks if you block it · Kilobat" url: "https://kilobat.app/hosts/icloud-com" description: "*.icloud.com covers Apple's iCloud services, from Private Relay to connection tests. What the domain serves, and why blocking all of it breaks iCloud." --- Sync and cloud storage # *.icloud.com Hosts under `icloud.com` run Apple's iCloud services. Apple lists the whole domain on port 443, and several hosts under it for specific jobs. Run by Apple · Ports: 443 TCP · Checked: 1 November 2026 ## Short answer Apple's iCloud domain. Apple lists *.icloud.com for iCloud services; specific hosts under it have their own pages. Don’t block Don't block the whole domain. Most iCloud services run under it, so iCloud sync, Private Relay and more stop. Matches `*.icloud.com` `icloud.com` A name with `*.` covers every name under it: `*.push.apple.com` matches `1-courier.push.apple.com`. ## What it serves Apple's enterprise host list names `*.icloud.com` in its iCloud section, for iCloud services. Devices also need Apple's Apple Account hosts to use iCloud. Hosts under it with their own entries: [`gateway.icloud.com`](https://kilobat.app/hosts/gateway-icloud-com) for CloudKit content, [`mask.icloud.com`](https://kilobat.app/hosts/mask-icloud-com) for Private Relay, [`probe.icloud.com`](https://kilobat.app/hosts/probe-icloud-com) for connection tests and [`metrics.icloud.com`](https://kilobat.app/hosts/metrics-icloud-com) for diagnostics. Kilobat matches the most specific entry first, so a connection to `gateway.icloud.com` shows that page, not this one. ## Processes that use it - [cloudd](https://kilobat.app/processes/cloudd): Part of macOS. It syncs the iCloud data of apps that use CloudKit, so its traffic belongs to those apps. - [bird](https://kilobat.app/processes/bird): Part of macOS. It runs iCloud Drive, so its traffic is your iCloud Drive files going up and down. - [cloudphotod](https://kilobat.app/processes/cloudphotod): Part of macOS. It does all iCloud Photos sync, so its traffic is your photos and videos going up and down. - [siriactionsd](https://kilobat.app/processes/siriactionsd): Part of macOS. It runs and syncs the shortcuts you make in the Shortcuts app, so iCloud sync of shortcuts can show under it. ## What breaks if you block it Don’t block Don't block the whole domain. Most iCloud services run under it, so iCloud sync, Private Relay and more stop. What breaks if you block it - iCloud Drive, iCloud Photos and app data in iCloud may stop syncing. - iCloud Private Relay and other iCloud features stop. With Kilobat Pro and the network filter, you can block a host for every app or for one app: in Connections, select a connection and choose Block. Apple’s own services are never blocked by Kilobat’s [Protection](https://kilobat.app/docs/blocking#protection) lists. ## Notes Apple also lists `*.icloud.com.cn` and `*.apzones.com` for iCloud services in China. ## Apple’s rules for its hosts Apple’s list, [Use Apple products on enterprise networks](https://support.apple.com/en-us/101555), says that devices open these connections, not Apple’s servers. Apple services fail any connection that uses HTTPS interception, so a proxy that inspects TLS should leave Apple’s hosts alone. If a firewall allows hosts by name, allowing `*.apple.com` covers most Apple services, Apple says. A firewall that works only with addresses can allow `17.0.0.0/8` for IPv4, and `2403:300::/32`, `2620:149::/32` and `2a01:b740::/32` for IPv6. To see which app on your Mac opened a connection to this host, use Kilobat’s Connections tab, or the [agent network log](https://kilobat.app/docs/agents#agent-network-log) for AI agents. ## Sources - [Apple Support: Use Apple products on enterprise networks](https://support.apple.com/en-us/101555) Checked on 1 November 2026. ## Related - [gateway.icloud.com](https://kilobat.app/hosts/gateway-icloud-com): Apple's CloudKit gateway. Apple lists it for CloudKit content, including XProtect malware definitions and Voice Control assets. - [*.icloud-content.com](https://kilobat.app/hosts/icloud-content-com): An Apple domain for iCloud services. Large uploads and downloads of iCloud content, such as files and photos, can go to hosts under it. - [*.apple-cloudkit.com](https://kilobat.app/hosts/apple-cloudkit-com): Apple's CloudKit service. Apps sync their iCloud data through it, and Apple lists api.apple-cloudkit.com for app notarization on macOS.