Exchange throttling policy for exchange migration
What is Exchange throttling?
To maintain optimal performance and prevent a single user from using up all server resources, on-premise Exchange servers use throttling policies. While this ensures the server remains healthy and accessible to all users, it can pose problems during migrations if too many mailboxes are migrated at once, resulting in performance issues. Exchange throttling sets a limit on the number of concurrent call requests that can be executed at a time. To avoid migration errors and guarantee a seamless process, it is recommended to create a new throttling policy specifically for migrations. With this, you can ensure that the migration runs smoothly and without issue, while minimizing any potential performance hiccups that may arise.
How to avoid Exchange server throttling?
EdbMails application is designed to migrate the email and other items granularly to avoid throttling issues. In addition, you can create a custom throttling policy with limits higher than the default ones or even disable these limits and assign it to the user account used in the EdbMails application to perform the migration.
Steps to create custom throttling policy in Exchange Management Shell (EMS)
- Launch Exchange Management Shell (EMS)
To increase the limits, first verify the current throttling policy by running the following command:
Command: Copy & Paste it on EMS
Get-ThrottlingPolicy | fl
To create a new throttling policy, run the following command:
Command: Copy & Paste it on EMS
New-ThrottlingPolicy <Name of the new throttling policy>
Example: New-ThrottlingPolicy EdbMailsPolicy
Throttling policy settings.
Ensure your backup or migration tasks are not limited by reconfiguring the new policy settings. You can disable the limits entirely by using $null or Unlimited values, or customize them as needed.
For Exchange Server 2010:
Command: Copy & Paste it on EMS
Set-ThrottlingPolicy EdbMailsPolicy -RCAMaxConcurrency $null -EWSMaxConcurrency $null -EWSMaxSubscriptions $null -CPAMaxConcurrency $null
For Exchange Server 2013 and newer:
Command: Copy & Paste it on EMS
Set-ThrottlingPolicy EdbMailsPolicy -RCAMaxConcurrency Unlimited -EWSMaxConcurrency Unlimited -EWSMaxSubscriptions Unlimited -CPAMaxConcurrency Unlimited -EwsCutoffBalance Unlimited -EwsMaxBurst Unlimited -EwsRechargeRate Unlimited
Note : Although the parameters mentioned above are essential for EdbMails Exchange migration, additional throttling policy limits can be modified. To learn more about adjusting throttling policies in Exchange 2010, 2013, 2016, and 2019, visit the Microsoft website.
To ensure that the new throttling policy takes effect, it must be assigned to specific accounts. Specifically, you need to set the throttling policy 'EdbMailsPolicy' for all the mailboxes that you want to migrate using the EdbMails software. Otherwise, the new throttling policy will not be utilized at all.
Use the following cmdlet to assign the newly created policy to the admin account.
Command: Copy & Paste it on EMS
Set-Mailbox "<mailbox name >" -ThrottlingPolicy EdbMailsPolicy
In place of <mailbox name>, enter the name or alias of the mailbox account utilized by the administrator.
To assign the throttling policy to all organization users, run the following cmdlet:
Command: Copy & Paste it on EMS
Set-ThrottlingPolicy “EdbMailsPolicy” -ThrottlingPolicyScope Organization
