How to enable maintenance mode in Dynamics 365

There are times when you will need to enable maintenance mode in Dynamics 365. In this article I will discuss the steps required to enable maintenance mode, as well as how to disable it again.

What is maintenance mode

Maintenance mode provides a safe way to make changes that affect system functionality. While maintenance mode is enabled, only system administrators and users with the role “Maintenance mode user” will be able to sign in to D365. While maintenance mode is enabled, only one interactive AOS will be available for use.

Reasons to enable maintenance mode

Maintenance mode is disabled by default, and will need to be disabled for regular day to day use. However there are times when it is needed to make changes to the system. The most common reason that maintenance mode is used is to edit the License configuration page. Since the configuration keys on this page affect system functionality, Microsoft has locked it down so that changes cannot be made while the system is in regular use. Another common reason maintenance mode is enabled is to force a database sync on a tier 2+ environment.

Enabling maintenance mode in a tier 1 environment

To enable maintenance mode in a tier 1 environment, you will first need to remote into the environment. Then open SQL Server Management Studio (SSMS) as an administrator. Once SSMS is open, expand the “Databases” node and right click on “AxDB”. This will open the quick menu where you can select “New Query”.

In the new query window, enter the following snippet of SQL code and press the execute button or F5 to run the update.

update [AxDB].[dbo].[SQLSYSTEMVARIABLES]
        set [AxDB].[dbo].[SQLSYSTEMVARIABLES].VALUE = 1
        where [AxDB].[dbo].[SQLSYSTEMVARIABLES].PARM = 'CONFIGURATIONMODE'

After the query has been ran, you should see the pop up “Query executed successfully” as well as a message saying (1 row affected). This means that the query has finished and maintenance mode as been enabled in the back end. If you do not see these messages, check that the query was entered correctly and try again.

Once this query has been ran successfully, you will need to initiate an iisreset. To do this, open a command prompt as an administrator and enter the command “iisreset”. You should see info messages like in the screenshot below.

Once the iisreset has completed the environment will be in maintenance mode. You will need to disable maintenance mode before the environment can return to regular use.

Disabling maintenance mode in a tier 1 environment

To disable maintenance mode in a tier 1 environment, you will need to reverse the query ran to enable it. Go back into SQL Server Management Studio and begin a new query on AxDB. We will be using the same query as was used to enable maintenance mode, except that the value will be changed to 0 this time.

update [AxDB].[dbo].[SQLSYSTEMVARIABLES]
        set [AxDB].[dbo].[SQLSYSTEMVARIABLES].VALUE = 0
        where [AxDB].[dbo].[SQLSYSTEMVARIABLES].PARM = 'CONFIGURATIONMODE'

Once again, run this query by pressing the “Execute” button or F5. Once it has ran you should see the pop up “Query executed successfully” as well as a message stating that one row was affected.

To finalize this change, open a command prompt as an administrator and enter the command “iisreset”. You should see info messages like in the screenshot below.

Once the iisreset has completed the environment will no longer be in maintenance mode, and will be available for regular use.

Enabling and Disabling maintenance mode in tier 2+ environments

Enabling and disabling maintenance mode in tier 2+ environments is handled relatively easily through LCS. Begin by navigating to the environment’s full details page. On the full details page, click the dropdown labeled “Maintain”. Under this menu, select the option named “Enable maintenance mode”.

To disable maintenance mode return to the environment’s full details page and click the dropdown titled “Maintain”. Under this menu you will se an option named “Disable maintenance mode”.

Selecting this option will begin the process of disabling maintenance mode. You should see a progress bar appear, and a status of “Exiting maintenance mode” in the top right.

Once the operation has completed, the environment will automatically come back online and be ready for normal use.

Conclusion

Maintenance mode is an important tool in D365 and is required for certain situations. Fortunately it can be used relatively easily by following the steps outlined in this article. For more information on maintenance mode, you can view Microsoft’s documentation here: Maintenance mode

Please feel free to chime in below with any questions or comments.

Tyler Mauer

Tyler Mauer works as a Senior Technology Consultant on the Managed Application Services team at RSM working on Microsoft Dynamics 365. His focus is in Retail and Commerce. When he is not solving problems or finding ways to accelerate his clients' business, he enjoys rock climbing and playing pinball.