MTX provides low-level driver programs that enable the control of various features of SCSI backup devices like autoloaders, tape changers, and others.
MTX is intended to be a low level driver program in a larger scripted backup solution, such as Amanda, rather than a high-level interface to the SCSI devices it controls. MTX boasts several key features such as its ability to manage large media libraries containing over a hundred elements, support for multi-drive media changers like the Exabyte 220 dual-drive tape library, and support for optical jukeboxes that require the invert bit to flip media.
It also supports eepos bits for libraries that need to extend/retract their import/export tray and import/export elements. MTX can also report volume tags (bar codes) and "alternate volume tags" for tape libraries that support them. The software runs under FreeBSD and at least Solaris 8 and has a 'man' page. The actual SCSI manipulation has been separated out into a library so that users can create their own "C" programs that manipulate SCSI media changers directly, though these programs must also be under GPL.
However, the program does have some limitations. Users may need to do a 'mt offline' (or equivalent for their OS) on the tape drive to eject the tape before issuing the 'mtx unload' command, as the Exabyte EZ-17 and 220 will continue to try to grab a tape that's not there. The 'next' command does not understand the 'invert' bit for optical jukeboxes, always advancing to the next slot instead of unloading, inverting, and reloading the same disk.
For some Linux distributions, users may need to recompile the kernel to scan SCSI LUN's to detect the media changer. Unloading a tape to its 'source' slot when it is full may result in the tape being placed in the first empty slot instead of the desired slot, which can cause SCSI errors. For big tape libraries, the software may set a big Allocation_Size, and some operating systems may fail this request due to memory limitations.
MTX may also have limited support for VMS and Tru64. It only uses the first arm of multiple-arm robots unless the robot remaps all arms to one element ID. It has been reported that this program works on Solaris 7 using the 'sst' driver and could work on Solaris 8 using the 'sgen' driver. The 'sst' driver can be found in the Amanda contrib directory.
Version 1.3.12: N/A