• User Manual

    Exchange Server Migration

User Manual

Exchange throttling policy for Exchange Migration

What is Exchange throttling?

On-premise Exchange uses throttling policies to ensure that a single user does not use up all the Exchange server resources. Normally, this ensures that the Exchange server remains healthy and available for all the users. However, during migration, if you migrate more mailboxes at a time, the Exchange server will throttle, and you will encounter performance issues. Exchange throttling imposes a limit on the number of concurrent call requests that can be executed at the same time. Therefore, it is advisable to create a new "migration" throttling policy in order to achieve error free migration.

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)

  1. To set the limits higher

    Verify the current throttling

    Command: Copy & Paste it on EMS

    Get-ThrottlingPolicy | fl

  2. Create a new throttling policy:

    Command: Copy & Paste it on EMS

    New-ThrottlingPolicy

  3. throttling policy settings.
    Use $null or Unlimited values to disable the limits or use custom values

    • Exchange Server 2010:

      Command: Copy & Paste it on EMS

      Set-ThrottlingPolicy NewPolicy -RCAMaxConcurrency $null -EWSMaxConcurrency $null -EWSMaxSubscriptions $null -CPAMaxConcurrency $null

    • Exchange Server 2013 and newer:

      Command: Copy & Paste it on EMS

      Set-ThrottlingPolicy NewPolicy -RCAMaxConcurrency Unlimited -EWSMaxConcurrency Unlimited -EWSMaxSubscriptions Unlimited -CPAMaxConcurrency Unlimited -EwsCutoffBalance Unlimited -EwsMaxBurst Unlimited -EwsRechargeRate Unlimited

    • Assign the admin account used in EdbMails application to the throttling policy

      Command: Copy & Paste it on EMS

      Set-Mailbox <mailbox name= " "> -ThrottlingPolicy NewPolicy

    • Assigning the throttling policy to all users in your organization

      Command: Copy & Paste it on EMS

      Set-ThrottlingPolicy "NewPolicy" -ThrottlingPolicyScope Organization