When using the AADSync tool to synchronise your Active Directory environment with Azure Active Directory (AAD), the default schedule for an incremental sync is 3 hours. This is done using a Scheduled Task. There are many reasons why you may want to change this schedule; maybe you have a high rate of change in your AD environment and you need a 1 hour sync to keep Office 365 up to date, or it might be that you have such a slow rate of change in your AD environment that you only want to sync your identities once every few days. It is worth mentioning that Password Synchronisation does not follow this schedule and is done immediately following a change of password, so this shouldn’t play a part in your decision to modify any scheduling of sync tasks.
Whatever your reasons, you are likely to become a little befuddled when trying to modify the regularity of your scheduled task. If you go into Task Scheduler, find the Azure AD Sync task and go into Properties, you can change the frequency of the task to make it run more or less often. However when you try to save the task it will ask you for the password of the account under which the task runs, the name of which looks something like ‘AAD_a6a4cefedc741’. It uses a random hex code at the end of the name so this could be slightly different to the example I’m using.
This account is used to run the AADSync service, is the account used to access the MIIS client database, and also to run the Scheduled Task. It is a local account which is created during the initial installation of AADSync, and the password is randomly generated. It may be tempting to change the password of this account, but please don’t. I have only come across this happening twice but both times have involved the internal database becoming completely inaccessible, meaning that the service simply won’t start, even with correct credentials.
If you really must change the frequency of your sync, create a new Scheduled Task and configure it to run the following application:
“C:\Program Files\Microsoft Azure AD Sync\Bin\DirectorySyncClientCMD.exe”
Ensure the Task is running with the highest possible priveleges and configure the task to use a user account which is a member of the following groups:
This new task will run under whatever schedule you fancy, and for good measure you can disable the original task if you’d like. When dealing with default configuration items in any piece of software, I would always recommend creating cloned configurations rather than modifying the default, as it gives you a way to back out of changes and allows you to compare old with new.