SIRIS, ALTO, and NAS: Getting Started with the ShadowSnap Agent



This article describes system requirements for the ShadowSnap Agent.

Do not install the ShadowSnap agent on any system currently protected by the Datto Windows Agent, even if you have uninstalled the Datto Windows Agent. Installing the ShadowSnap Agent will start a new backup chain for the protected system and will not continue your existing backup chain.


  • ShadowSnap Agent


Agent Details

In addition to our own Datto Windows Agent and Datto Linux Agent, Datto also supports the third-party ShadowSnap Agent.

We recommend the ShadowSnap Agent if:

  • You have used the ShadowSnap Agent to back up the host in the past.
  • You need to protect a Windows XP OS, Windows 2000 OS, or Windows Server 2003 OS.
  • You need to protect a host which does not and cannot have internet connectivity.


The current version of ShadowSnap is version 4.0.0, and it works in conjunction with ShadowProtect MSP version 5.0.1. You can download the latest version of the ShadowSnap Agent software at

You can check your protected machine's installed version from the Protect tab of your Datto appliance's GUI.

The ShadowSnap Agent does not automatically update. When an update becomes available, you will need to download and install it manually, and then reboot the protected machine to finalize the installation.


  • Backup and restore of deduplicated volumes is unsupported.
  • Before installing the ShadowSnap Agent, disable or remove all other backup software from the production machine. Use a high-level uninstaller that removes all traces of the program after deployment, including registry keys, DLLs, and stray folders. These components can cause conflicts.
  • Before installing the ShadowSnap Agent, ensure that the Volume Shadow Copy Service of the protected Windows machine is Enabled.
  • Acronis software can prevent the installation of the ShadowSnap agent. For any machine that previously had an Acronis product installed, follow the steps in the Removing Acronis article to perform system cleanup.
  • The date and time settings on the protected machine must correspond with the correct time zone in which the Datto appliance device resides.
  • There is a known issue between the Synaptics Touchpad Driver and the VirtualBox Guest Additions software used by the ShadowSnap agent:
    • Older versions of the driver can cause a Blue Screen of Death (BSOD) failure
    • Synaptics Touchpad Driver Version - 9/15/11 is compatible.
    • Subsequent versions can accept the ShadowSnap installer.
  • Due to their mobile nature, Datto does not endorse or support backing up laptops. Laptops must be inside the LAN, and not on a wireless network, to perform backups promptly. Attempts to back up laptops are at your discretion. Due to this consideration, and because of the range of touchpad drivers, custom drivers, and hardware configurations available for both laptops and all-in-one workstations, restoration support for these platforms is 'best-effort' only.
  • The Datto solution is capable of backing up multiple types of disk sector schemes. The process writes an image-based backup to a file that is 512 bytes per physical sector. While rare, certain software which relies on advanced formats, such as 4K, may have issues with the sector size change. Datto recommends performing regular DR tests to ensure that all required applications function as expected in our virtualized environments.
  • The ShadowSnap Agent can only back up volumes that the Windows operating system recognizes as logical, stable volumes. It cannot back up mapped network drives, iSCSI targets without an associated logical volume, or removable drives.

Compatibility and System Requirements

See the System Requirements For Windows-Based Backup Solutions article for a complete list of the ShadowSnap Agent's system requirements and supported operating systems. Datto does not test the compatibility of this backup solution with any hypervisor environment or operating system not listed in the article.

Review the Windows Pre-Deployment Configurations and Best Practices to ensure that your production machine is in a ready state for protection by the ShadowSnap agent.

Finally, see the StorageCraft Server Tuning Guide for important information about improving the reliability of ShadowSnap backups, including proactively resolving network latency issues or disk input/output issues. Since these steps involve manipulating the registry, take a backup of the protected machine's registry before making any changes. StorageCraft provides a downloadable tool to analyze a system for ShadowProtect compatibility, which is available here.

To ensure successful backups, ensure that the protected machine has a minimum of 20% free space per protected volume and 1 GB of RAM. If resources fall below these thresholds, backup attempts can fail.

 Volume Utilization



0 – 70%


Utilization is good.

71 – 80%


Utilization is outside optimal limits. Monitor the volume growth and look at cleaning up unnecessary files and moving non-essential data to other storage.

81 – 100%


Volume is becoming critical. Snapshots will start to fail, and disk queue lengths will increase. Create space.

Networking Requirements

The following are the minimum networking requirements your environment must meet to support the ShadowSnap Agent. For a complete overview of Datto's networking requirements, see the SIRIS, ALTO And DNAS Networking & Bandwidth Requirements article.

  • Connect the Datto appliance to a Gigabit switch. Datto also recommends connecting protected machines to a Gigabit switch whenever possible.
  • Firewall rules:
    • From the protected machine to the Datto appliance: TCP 3260 (iSCSI port), TCP / UDP 445, TCP / UDP 139
    • From the Datto appliance to the protected machine: TCP 25566. TCP 25566 is live only when the StorageCraft Raw Agent service is enabled and running. Use the netstat command to verify
    • From the protected machine to Internet: TCP 80 outbound to (
    • From the Datto appliance to the Internet: 22, 80, 123, 443 outbound to the addresses specified in this article

Figure 1: ShadowSnap Agent and ShadowSnap Encrypted Agent logical data flow (click to enlarge)


Before installing the ShadowSnap Agent, to ensure an issue-free setup experience, review our System Requirements For Windows-Based Backup Solutions and Windows Pre-Deployment Configurations and Best Practices guides. Then, follow the steps in Installing the ShadowSnap Agent to deploy the agent to your production machine.

Additional Resources

Was this article helpful?

22 out of 27 found this helpful

You must sign in before voting on this article.

Want to talk about it? Have a feature request?

Head on over to our Datto Community Forum or the Datto Community Online.

For more Business Management resources, see the Datto RMM Online Help and the Autotask PSA Online Help .

Still have questions? Get live help.

Datto Homepage