Does Azure AD Domain Services provide AD account lockout protection?
Yes. Five invalid password attempts within 2 minutes on the managed domain cause a user account to be locked out for 30 minutes. After 30 minutes, the user account is automatically unlocked. Invalid password attempts on the managed domain don't lock out the user account in Azure AD. The user account is locked out only within your Azure AD Domain Services managed domain. For more information, see Password and account lockout policies on managed domains.
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