One can attach up to seven external USB hard drives to the My Cloud using a powered USB hub. The My Cloud User Manual (http://www.wdc.com/wdproducts/library/?id=439&type=25) specifically mentions this in Chapter 12 Connecting a USB Hard Drive. Once a USB hard drive is attached and is properly mounted the drive will show up as a Share where one can set the Public/Private option along with the Media Serving option. When Media Serving is enabled the Twonky media server embedded within the My Cloud will catalog the supported media on the drive.
If one wants to have the Twonky media server “aggregate” the media stored on another Twonky media server or Windows Media Player, they can access the Twonky media server’s aggregation page via the Twonky administration page usually found at http://wdmycloud:9000. From that page:
Aggregation
When Aggregation is enabled, Twonky Server collects information from any other device running Twonky Server or Windows Media Player and presents all available media from your network in one comprehensive view. With this feature, you will not need to switch between different servers when searching for a particular media item. Twonky Server will automatically hide duplicates.
One should review the following link for more suggestions on how to get the best use out of the Twonky media server.
https://community.wd.com/t/faq-twonky-dlna-media-server-setup-use/95373
One can use the Safepoint / Backup option of their My Cloud to backup any data on their My Cloud to a separate My Cloud, USB hard drive or other network location. See the My Cloud User Manual for more information on how to setup and use Safepoint / Backup.
If one needs a dedicated content management system they will have to look elsewhere, the single bay My Cloud doesn’t officially support any sort of content management system or other media server other than Twonky and iTunes (music only). Twonky is a limited basic media server. Unofficially there are a number of software packages one can install to the older v4.x single bay My Cloud units. See the following link.
https://community.wd.com/t/repository-with-software-worked-on-v4-firmware/94532
