IBM DLT-DDS tape diagnostics v5.8.1 for Linux, here: http://www-947.ibm.com/support/entry/portal/docdisplay?lndocid=MIGR-5073761&brandind=5000008
and for Windows: http://www-947.ibm.com/support/entry/portal/docdisplay?lndocid=MIGR-5073759&brandind=5000008