Capacity and Scale Considerations in MDM

  • Article

2/9/2009

As you consider your options to implement Microsoft System Center Mobile Device Manager (MDM) 2008 Service Pack 1, you should forecast your future requirements for managing Windows Mobile devices. The sections in this topic describe capacities achieved for MDM 2008 SP1 systems and components in laboratory installations under the indicated test scenarios.

For information about the specific hardware specifications that are used to achieve the capacities listed in this topic, see the last section, Hardware and Configurations Used to Develop Capacity Information. For more information about hardware requirements for all MDM servers, see System Requirements for MDM Servers and Managed Devices in this document.

Server Capacities

The number of devices that an MDM 2008 SP1 system can support depends on the hardware that you install and how your system is configured. The following list summarizes how many Windows Mobile devices can be supported by the components of an MDM system.

  • An MDM instance can support up to 60,000 devices.

Note

You cannot generate status summary reports for more than 45,000 devices when the devices are in one Active Directory group.

  • A server running MDM Device Management Server can support up to 15,000 devices.
  • A server running MDM Gateway Server can support up to 15,000 devices.
  • A server running MDM Enrollment Server can support up to 25 concurrent device enrollments.

On an MDM Gateway Server That Has 15,000 Managed Devices

You can manage up to 15,000 devices on each server that is running MDM Gateway Server if your MDM system meets the following conditions:

  • One hundred percent of the managed devices can have an active virtual private network (VPN) connection.
  • Up to 60 percent of the devices can have active network sessions through VPN.
  • Each MDM Gateway Server can support traffic volumes up to 100 megabits per second (Mb/s).
  • There may be up to 16 servers running MDM Gateway Server in an MDM instance.

On an MDM Device Management Server That Has 15,000 Managed Devices

You can manage up to 15,000 devices on each server that is running MDM Device Management Server if your MDM system meets the following conditions:

  • Each managed device contacts MDM Device Management Server up to one time every eight hours.
  • Policies are updated every eight hours on all devices.
  • Device history is set to 15 days and the Open Mobile Alliance (OMA) scheduled session interval is set to eight hours.

Note

You can run the Set-DeviceManagementConfig cmdlet in MDM Shell to modify these values. For example: Set-DeviceManagementConfig -ConnectInterval (New-Timespan -hours 8) –HistoryDuration (New-Timespan -days 15)

  • You can deploy up to four computers that are running MDM Device Management Server in an MDM instance.

Note

The total number of managed devices should not exceed the total capacity for an MDM system. Therefore, even with more than four servers running MDM Device Management Server, the total capacity for the MDM instance remains at 60,000 devices.

  • Use a fast data network for best load-reduction results.

On a Single MDM Enrollment Server

One server that is running MDM Enrollment Server can support an entire MDM instance because it actively supports devices only during the enrollment process.

  • Up to 25 concurrent enrollments can be in progress.
  • You can have up to four servers that are running MDM Enrollment Server in an MDM instance.

Hardware and Configurations Used to Develop Capacity Information

Server capacities vary by installation and are highly dependent on the frequency of device monitoring sessions, software distribution, policy changes, and installed hardware.

The following lists the hardware and software installed, as well as the log file configurations under which the capacity information in this section was tested.

MDM servers hardware for MDM Enrollment Server and MDM Device Management Server:

  • Processor: Dual processors at 2.0 gigahertz (GHz) CPUs
  • RAM: 4 gigabytes (GB)
  • Hard drive configuration: SCSI (non-RAID)

MDM servers hardware for MDM Gateway Server:

  • Processor: Dual processors at 2.3 GHz CPUs
  • RAM: 2 GB
  • Hard drive configuration: SCSI (non-RAID)

SQL Server hardware:

  • Processor: Dual processors at 2.0 GHz CPUs
  • RAM: 4 GB
  • Hard drive configuration: RAID 0 (simple striping)
  • Operations log files and transaction log files are on separate hard disk drives
  • Data log files and transaction log files are on separate hard disk drives

In addition, the following lists the most common variables that can affect capacity in an MDM system:

  • Server Hardware: processor speed, number of processors, cache, memory, disk I/O subsystem, or network
  • SQL Server Hardware: Adherence to SQL Server scalability best practices, particularly around the disk I/O and memory management
  • Frequency of configured device polling
  • Frequency, scope, and types of policy changes
  • Frequency of sending and detection rules for software distribution packages
  • Inventory items which are collected and the frequency of these inventory jobs
  • Number of managed device containers against which Group Policy settings are managed. The most MDM resource-intensive model is one in which all the devices are contained within a single root container, and all Group Policy settings are applied to this root container.
  • Number of distinct software distribution groups and scheduling of distribution to each of these groups. Multiple WSUS-targeted groups on independent schedules create less load than if you include all managed devices in a single targeted group.
  • Device wireless network data speeds: faster network speeds lessen the burden on the MDM system.