Migrating Distro Groups from Exchange to Office 365, part 4
In steps 4 and 5 of part one I wrote,
4. Delete on-premises groups. After verifying that I had all the data I needed to rebuild them in the cloud (or on-premises if necessary), I removed the original groups…
5. Rename and address online groups. I wrote a third PowerShell script (Address_DistroGroup.ps1) that renames the new online groups to the old on-premises group names and adds the email addresses extracted in step 1.
Let me repeat this: Be very careful on Step 4. Make sure that you have good data in your exported files and that you have a good backup before proceeding.
Once you’ve deleted the original on-premises groups and synced your on-premises directory to the cloud, connect to Exchange Online and run this script to apply the old on-premises group’s names and addresses to the online group:
# xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
# Filename: Address_DistroGroup.ps1
# Version: 2016.03.31
# Purpose: Imports the email addresses of groups that were exported
# by the Export_DistroGroup.ps1 script.
#
# Usage:
# Address_DistroGroup "Group Name"
# "Group Name" must be the exact name of the group in the on-premises
# Exchange organization and the on-premises group must already be
# deleted and the directory synced to Exchange Online.
#
Param(
[string]$Group
)
# Specify the path of your input files. This should be the same as
# the OutPath from Export_DistroGroup.
$InPath = "C:\Temp\Groups\"
# If the Completed folder doesn't exist, create it.
$CompletePath = $InPath + "Completed\"
if (-not (Test-Path $CompletePath)) {
New-Item $CompletePath -Type Directory
}
# This tells the script where to find the list of addresses.
$AddressesFile = $InPath + $Group + "-Addresses.csv"
# Assumes that your original online group creation
# appended " OL" to the name of each group.
$OldName = $Group + " OL"
# xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
if (Test-Path $AddressesFile) {
# Adds the list of addresses to the online group.
Write-Host "Adding group addresses..."
$Addresses = Import-CSV $AddressesFile
$Addresses | Foreach {
if ($_.ProxyAddressString -like "smtp*") {
Set-DistributionGroup $OldName `
-EmailAddresses @{add=$_.ProxyAddressString.toLower()}
}
elseif ($_.ProxyAddressString -like "X500*") {
$X500addy = "x500:" + $_.AddressString
Set-DistributionGroup $OldName `
-EmailAddresses @{add=$X500addy}
}
}
# Renames the group from "Group Name OL" to "Group Name".
Set-DistributionGroup $OldName -DisplayName $Group -Name $Group
# Moves the address file to the "Completed" folder.
Move-Item $AddressesFile -Destination $CompletePath
}
|
Do I have to say it again? Of course, not. You’re way too smart to need this. Unfortunately, somebody out there–we’re not saying who–might not be. Here it is: TEST and VERIFY. Don’t just trust me that this process will work. Check every line and test it first.
► Part 1 – Overview of the process I used to migrate my Exchange distribution groups to Office 365.
► Part 2 – Exporting your on-premises distro group settings to CSV files.
► Part 3 – Importing your group settings from the CSV files to Exchange Online.
► Part 4 – Renaming and addressing your online distro groups.
► Part 5 – Rebuilding your Dynamic Distribution groups online.
[Update 4/1/2016 – Corrected code to properly handle X500 addresses and rename the group after addressing.]