I can't seem to get tapetype to agree to the rated capacity of my
Powervault 120T (DLT 7000 35G native).

The maximum uncompresses that tapetype registers is about 27G.

Running 'mt status' returns a density code for 35G.

Any ideas why I can't detect the full tape?

Here's the output from tapetype.

Writing 128 Mbyte   compresseable data:  28 sec
Writing 128 Mbyte uncompresseable data:  28 sec
Estimated time to write 2 * 1024 Mbyte: 448 sec = 0 h 7 min
wrote 860664 32Kb blocks in 2632 files in 24789 seconds (short write)
wrote 855261 32Kb blocks in 5247 files in 33707 seconds (short write)
define tapetype unknown-tapetype {
    comment "just produced by tapetype prog (hardware compression
off)"
    length 27065 mbytes
    filemark 66 kbytes
    speed 961 kps
}

Russell