USB duplication best practices
These boards help us a lot when testing on different PCs, because they can easily be carried around and are connected with only four cables (incl. power).
Take two of these boards, and you can handle 198 sticks being written in one pass on one PC. In the event, that an individual stick fails, ProtectUSB’s layout feature allows you to locate the stick in an instant and retry with the next pass or discard it.
To handle such many USB ports/sticks in parallel, it is all important to follow a few basic guidelines. Without them, the process will fail or will slow down significantly.
Below is the list of the recommended best practices. Make sure to follow them and you’ll be happy with the results. Don’t follow them, and you’ll likely run into problems.
Selecting USB flash drives
- USB flash drives consist of several components; PCB board, USB connector, controller chip, memory chip, and case. Poor quality components can affect the performance and even cause the drive to fail in the field.
- High-quality drives with Tier 1/Grade A, branded original memory should be used. Original memory is manufactured by Samsung, Toshiba, Intel, Micron, and Hynix. You should see the brand name on the memory chip if opening the drive case.
- Alcor's controllers are recommended, however Silicon Motion (SMI) and Phison generally work well.
- Samples with protected content should be tested on both supported operating systems for both Mac and Windows before placing bulk orders.
- Certain controllers support hardware write-protection. This has nothing to do with the content encryption. The content will be encrypted regardless, but hardware write-protection allows physically locking the drives, so no files can be added or deleted.
- You can find a list of controllers that support hardware write-protection in the USB Tools directory after installation of ProtectUSB Content or ProtectUSB Software.
Configuring your operating system settings
- Do not run any antivirus software (this includes out-of-the box solutions as Windows Defender). Disabling is often not enough, and uninstalling is highly recommended. Antivirus software is known to cause system instability issues (especially in connection with USB drives) and causes a huge resource drain when writing to a large amount of USB drives in parallel.
- Disable power-saving schemes of the computer used for writing.
- Disable auto-insert notification (e.g. as described here: https://technet.microsoft.com/en-us/library/cc959381.aspx).
- Disable the Search Indexer Service.
General computer hardware considerations
- You can connect significantly more USB2 devices than USB3 devices. Therefore, if you don’t specifically aim at USB3, it is recommended to use USB2 controllers and USB2 hubs (or USB3 hubs connected with USB2 cables) for the duplication.
- You should keep the USB hub device tree flat by connecting as many hubs as possible directly to the root USB hub, instead of “daisy-chaining” from one hub to the next.
- One USB root hub can control up to 127 endpoints, which are hubs and USB sticks. Since a physical hub often contains multiple logical hubs and a USB stick usually contains 2 end points, you can connect about 50 USB sticks per root controller for USB2. With USB3 this is a fraction, often about 1/3.
- In addition to the root hub on the motherboard, you can add additional USB controller cards. It is no problem to mix different bus types, such as PCI-Express or PCI. Note that although these cards may have multiple connections, they still have only one (max. 2) root hubs.
- The computer you use for writing should be well-equipped with RAM to be able to cache the source data. Processor speed is less important, and even older models generally do fine.
- Source content must be located on a fixed hard drive and cannot be prepared from a USB drive to prevent overload of the USB buses.
- The fixed hard drive should have a minimum of 3 times larger than the total size of the source content, as well as another 1 GB of drive space for operating system housekeeping.
- Use high quality, separately powered USB hubs with as many ports as possible (>10 ports per physical hub is a good number).
- Make sure the hubs you use are stable, preferably hard mounted to a solid underground and the ports are easily accessible (e.g. from the top) as you will insert/remove numerous sticks.
- Use hubs with LED indications for inserted/active sticks. This way, you can directly tell if an inserted stick is working.
- The USB sticks you use are an important (very often dominating) factor for the overall speed.
- Do not change/disconnect hubs as this breaks the physical layout’s port associations.
- If you switch on power to hubs with inserted sticks, do this one by one and not all at the same time.
- Be aware that the first symptoms of the computer not being able to handle the amount of sticks are random non-working ports. In this case, you should reduce the number of ports/sticks and/or change your configuration/components to stabilize the system.
Configuring the ProtectUSB software
- IMPORTANT: Using the “Strict Mode” is highly recommended. This mode is turned on in the Settings of the “Write Flash Drives” app. Strict Mode requires that the License checkbox is enabled, that the sticks report the necessary information, and forces a bit-to-bit verification of the data written on the sticks to the source data. This will help assure that the sticks you duplicate work in the field. Of course, you should also have a good quality assurance process in place as well.
- The source data for the duplication should be on a fixed, local drive (no network share or removable ). This is especially important if you write the data on multiple computers in parallel. This way the network load is reduced and the network or USB bus does not become a bottleneck.
- You need to define a physical layout and map the ports of your hubs to it. This has the following benefits:
- You will get a warning if a port/stick is not detected correctly
- You are able to directly identify a failed stick’s physical location after the write process
- It is critical that the sticks are written using the same Product ID as used when the content is packaged during the content preparation. If they are not the same, you will get a media cannot be authenticated when running a duplicated stick.
- You need to define a physical layout and map the ports of your hubs to it. This has the following benefits:
- You will get a warning if a port/stick is not detected correctly
- You are able to directly identify a failed stick’s physical location after the write process
Implementing a QA process
- We recommend implementing a quality assurance plan to minimize the chance of corrupted or defective sticks from shipping to your customers. This plan should include:
- Checking protected drives on all supported platforms on the initial run and spot checking passes during production. The best practice would be to check a drive from pass on each duplication system on both Mac and Windows.
- Checks should be performed on Mac and Windows computers other than those computers for the packaging and duplication.
- You should make certain to re-package any content if a new version of the Flux Player version has been released in ProtectUSB Content.
- If duplicating the same content on multiple systems, we recommend using an app such as TeraCopy (http://codesector.com/teracopy) with verification to assure the data is not corrupted during transfer.
Troubleshooting during production
- If you get a “Media cannot be authenticated” error when running a duplicated stick, confirm that the sticks are written using the same Product ID as used when the content is packaged during the content preparation. This is critical as the Product ID identifies the content and must be the same in both the packaging and writing process or the authentication process will fail.
- If you have confirmed the Product ID is correct and tested the drive on a different computer, try using a different brand/model flash drive to learn if the result is the same. If so, contact your account representative or support@protect-software.com.