Removable Mass Storage (RMS)
RMS is a type of device and media that is high capacity, random access, and interchangeable between systems and partitions.
RMS devices and media are similar to optical storage in regard to behavior and access interfaces. They are managed and used with existing optical device functions and commands. See Optical storage as a reference guide for use of these devices and media. RMS media are handled the same as optical volumes, and as such are also accessible through the QOPT file system by using the hierarchical file system (HFS) and integrated file system (IFS) APIs. RMS media are formatted with the industry standard Universal Disk Format (UDF) version 2.5.
Two types of RMS devices and media are supported. Removable disk (RDX) cartridges are media that contain a spinning disk. The other is flash drive, which reports as Device Specific Media or *DEVICE mass storage. The media and devices are used as a backup and recovery solution for IBM i systems that can take advantage of the moderate throughput and the lower price of removable disk or flash drives.
RDX devices can be attached with SATA or USB interfaces and can be hosted to a virtual client partition. Devices that report as *DEVICE must be attached to the USB interface and can also be hosted to a virtual client partition.
|Hardware resource type and model
|RDX (virtual client of IBM i)
|RDX (virtual client of VIOS)
|Device-specific (virtual client partition)
RMS Media Types
RDX capacities range from 160 GB to 2.0 TB. RDX media displays with media type *RDX.
IBM i allows the use of any flash drive that complies with the Universal Serial Bus Mass Storage Class. Flash drives display with media type *DEVICE.
- A USB 2.0 device (up to 32 GB in capacity) attached to a USB 2.0 system unit port.
- A USB 3.0 device attached to a USB 3.0 port (adapter or system unit) with up to 256 GB
capacity.Note: Support for a USB 3.0 flash drive with a capacity greater than 32 GB requires 7.2 PTF MF63610 or 7.3 PTF MF63611.
RMS Media Formats and Interchange
RMS media is formatted by the IBM i operating system with industry standard Universal Disk Format (UDF) version 2.5. Media that are recorded with UDF version 2.0 and 2.01 are also accessible for read or write. Media that are recorded with prior UDF versions are accessible as read-only.
Removing USB Storage Devices
Devices with an eject button, DVD, RDX, and tape drives, ensure that the media is properly quiesced and all the data is stored on the media before the device is ejected. Flash drives need an operation that is performed to ensure that the data is written to the media to allow the device to be safely removed. On IBM i use VRYCFG STATUS(*OFF), or use RMVOPTCTG or option 4 on WRKOPTVOL to eject the media. If the media is logically ejected, a flash drive reports that it is empty until the RMS device description is varied off/on or the Add Optical Cartridge command (ADDOPTCTG) is used to logically add the media back to the flash drive.
With 7.3 TR1 and later releases, support is added for optical container media. Container media allows optical image catalog entries to be stored on physical optical media within a RDX or flash drive.
Container media is created by using the Initialize Optical (INZOPT) command with a Volume type parameter value of *CONTAINER.
When optical container media is created, a virtual optical device of type/model 632B-011 is automatically created and associated with the physical RDX or flash drive device. This virtual optical device is used to work with any image catalog entries within the container media. If the automatically created virtual device is named OPTVRT01, the following command would be used to work with the image catalog entries: WRKIMGCLGE *DEV OPTVRT01
The new QMOCRTCV API can be used to add image catalog entries to the container media. See the QMOCRTCV API for more information.
For more information about container media support, see IBM Removable Media on IBM i.