When using Exchange online in Hybrid mode , if you want to have a unified global address list with exchange online users and onpremise users then you need to create on premise blank mailboxes for the users that you want to use exchange online and then create ‘remote move requests‘ to move the onpremise mailboxes to exchange online.
During the move request , if you open the log you may see ‘Relinquishing job because the mailbox is locked‘
So in order to fix this and really speed up the remote move requests we need to go to the intrusion prevention section of TMG and then the Behavioral Detection\Configure Flood Mitifgation Settings as per the image below.
We click on the link for Configure Flood Mitigation Settings and then click on ‘IP Exceptions‘ and create a new computer set. In the image below I called it ‘Exchange Online Protection‘ and add a computer set with the exchange online protection range as per the image below
All of the Exchange Online Protection IP ranges can be found at this SITE
You can susbscribe via RSS feed HERE to the Microsoft Online IP Ranges
So now Remote move requests will migrate a lot quicker 🙂