---
title: "idmsa.apple.com: what it is and what breaks if you block it · Kilobat"
url: "https://kilobat.app/hosts/idmsa-apple-com"
description: "idmsa.apple.com and gsa.apple.com authenticate your Apple Account. Why every Apple service needs them, and what breaks if you block them."
---

Security and accounts

# idmsa.apple.com

`idmsa.apple.com` and `gsa.apple.com` authenticate your Apple Account. Apple says that this is required for every service that uses an Apple Account, such as iCloud, app installs and Xcode.

Run by Apple · Ports: 443 TCP · Checked: 1 November 2026

## Short answer

Apple's Apple Account authentication hosts. Signing in to iCloud, the App Store and Xcode needs them.

Don’t block

Don't block them. Signing in to your Apple Account fails, and with it iCloud, the App Store and Xcode sign-in.

Matches

`idmsa.apple.com` `gsa.apple.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 both in its Apple Account section, for “Apple Account authentication”, on port 443, with proxy support.

Apple says that devices must reach the Apple Account hosts to authenticate an Apple Account.

On a Mac, Apple Account sign-in goes through AuthKit, whose daemon is [`akd`](https://kilobat.app/processes/akd). Apple doesn't document which process contacts which host.

## Processes that use it

- [akd](https://kilobat.app/processes/akd): Part of macOS, not documented by Apple. It is the AuthKit daemon, and its launchd services cover Apple Account sign-in and Sign in with Apple.

## What breaks if you block it

Don’t block

Don't block them. Signing in to your Apple Account fails, and with it iCloud, the App Store and Xcode sign-in.

What breaks if you block it

- Signing in to iCloud, the App Store, Xcode and other Apple services fails.
- Two-factor checks and password confirmations may fail.

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.

## 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)
- [Apple Platform Security: Apple Account security](https://support.apple.com/guide/security/apple-account-security-secbd5822138/web)

Checked on 1 November 2026.

## Related

- [account.apple.com](https://kilobat.app/hosts/account-apple-com): Apple's hosts for Apple Account authentication in Settings and System Settings.