ArcGIS Server provides a read-only mode that allows you to control changes to the site. Enabling this mode prohibits the publishing of new services and blocks most administrative operations. Your existing services function as they previously did. For example, you can still edit data in feature services when the site is in read-only mode.
By default, your site is set to editable mode. This means that the site is open to administrative configuration and new services can be published. See Change the ArcGIS Server site mode for steps on how to switch between site modes in Manager.
Certain administrative operations are still available in read-only mode, such as adding or removing machines from a site and querying logs. See Administrative operations and ArcGIS Server site mode for a list of which administrative actions are available and which are disabled when the site is in read-only mode.
Starting at 10.8, the ArcGIS Enterprise portal also has a read-only mode, which places all federated servers into read-only mode. That mode is separate from the ArcGIS Server read-only mode, but a federated ArcGIS Server site can be made read-only from either the portal or from ArcGIS Server Manager.
When you switch to read-only mode, site configuration files are copied to a local repository on each machine in the site. This allows the site to read from the local repository in the event of a failure connecting to the configuration store and input directory. The site can operate in a degraded capacity that allows access to the ArcGIS Server Administrator Directory, ArcGIS Server Manager, and ArcGIS Services directory, and keeps most services running as expected.
If the site is operating in a degraded capacity, the limited administrative operations that function when the site is in read-only mode are no longer available. Your services will function as expected with the following exceptions:
- Geoprocessing services will not work.
- Consumption of cached services will not work unless they are highly available.
- Exporting a map or image service using a URL is not possible.
The jobs and output directories for a multiple-machine site remain in their shared location when the site is in read-only mode. They are not copied to each local machine.
A site that is in read-only mode cannot be federated. Only editable sites allow federation. Once the site has been federated, however, you can switch the mode to read-only.
Hosting server sites cannot be set to read-only mode. Sites that are in read-only mode cannot be designated as hosting server sites. To place a hosting server into read-only mode, use the portal's mode setting.
Advanced site mode configuration
By default, switching to read-only mode will copy site configuration files to a local repository on each machine in the site. Your services will also be restarted. To change this default behavior, you will need to edit properties in the ArcGIS Server Administrator Directory. For instructions or more information about advanced site mode configuration, see Advanced site mode configuration.
Recovery of a site
You can recover a site that is in read-only mode if its connection to the shared configuration store is lost. See Recover a site for details.
When you upgrade your site, the mode will be set to editable for you if you have not already switched to editable mode. After all machines in your site have been successfully upgraded, the site will remain in editable mode. You can switch back to read-only mode once your upgrade is complete.