private/helper/dns/Get-DnsOnmicrosoftDomain.ps1
function Get-DnsOnmicrosoftDomain { <# .SYNOPSIS Get <customer>.onmicrosoft.com domain for the tenant. .DESCRIPTION Get initial domain through Microsoft Graph. .NOTES Requires the following modules: - Microsoft.Graph.Identity.DirectoryManagement .PARAMETER Domain Domain to resolve. .EXAMPLE Get-DnsOnmicrosoftDomain; #> [cmdletbinding()] param ( ) BEGIN { # Write to log. Write-CustomLog -Category 'DNS' -Subcategory 'Microsoft 365' -Message ('Getting all Microsoft 365 managed domains') -Level Verbose; # Get domains. $domains = Get-MgDomain -All; # Variable to store initial domain. [string]$initialDomain = ''; } PROCESS { # Foreach domain. foreach ($domain in $domains) { # If domain is initial domain. if ($domain.IsInitial -eq $true) { # Set initial domain. $initialDomain = $domain.id; # Write to log. Write-CustomLog -Category 'DNS' -Subcategory 'Microsoft 365' -Message ('Initial Microsoft 365 domain is "{0}"' -f $initialDomain) -Level Verbose; # Break loop. break; } } } END { # Return initial domain. return $initialDomain; } } |