In (classic) Central, with Cloud Guest, the default is to use the built-in SMS service. You can optionally, under SMS Providers, configure your own Twilio account.
I just tested with my (Netherlands) phone, and I receive the SMS with sign in credentials.
In some countries, SMS from outside the country, or unregistered (with the government) entities is blocked/prohibited; that's why you can configure your own account, which also allows 'branding' it to your own organization, and Twilio probably is registered in most countries where that is required. There are also some cellular providers that block SMS messages that they believer are spoofed/phishing; like the messages Central sends in bulk through the same SMS provider for all of it's customers. This worked in the past, but has become more and more obsolete. So it depends on the country and provider if the messages arrive. If you have issues, best you can do is get a Twilio subscription and use that.
Going forward, having your own SMS provider will be the way to go as because of the issues mentioned, in Central NAC the HPE provided SMS service will be dropped.
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Herman Robers
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If you have urgent issues, always contact your HPE Aruba Networking partner, distributor, or Aruba TAC Support. Check
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Original Message:
Sent: Sep 18, 2025 11:00 AM
From: Matthew King
Subject: Aruba Cloud Guest Splash Page
Perhaps thats the case, our SE hasnt indicated that while speaking about this though.