Cannot mount LTFS -- parser error

[neekolas86]

I'm using a Quantum LTO6 drive with an HP LTO-6 Ultrium 6.25TB MP RW Data Cartridge
(C7976A).  Any suggestions on how to fix this tape (or at least recover the data) would be much appreciated!  

Best regards,

Nick

Edit:  I'll add that other tapes are able to mount successfully and that the drive was recently cleaned using its provided cleaning tape.

sudo LD_LIBRARY_PATH=/usr/local/lib ltfs -o devname=/dev/st0 /mnt/ltfs
[sudo] password for integral:
LTFS14000I LTFS starting, LTFS version 2.1.0, log level 2
LTFS14058I LTFS Format Specification version 2.1.0
LTFS14104I Launched by "ltfs -o devname=/dev/st0 /mnt/ltfs"
LTFS14105I This binary is built for Linux (x86_64)
LTFS14106I GCC version is 4.6.3
LTFS17087I Kernel version: Linux version 3.2.0-29-generic (buildd@allspice) (gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) ) #46-Ubuntu SMP Fri Jul 27 17:03:23 UTC 2012 i386
LTFS17089I Distribution: DISTRIB_ID=Ubuntu
LTFS17089I Distribution: NAME="Ubuntu"
LTFS14063I Sync type is "time", Sync time is 300 sec
LTFS17085I Plugin: Loading "ltotape" driver
LTFS17085I Plugin: Loading "unified" iosched
LTFS20013I Drive type is Quantum LTO6, serial number is HU140817YY, firmware revision is 4142
LTFS17160I Maximum device block size is 1048576
LTFS11005I Mounting the volume
LTFS11026I Performing a full medium consistency check
Entity: line 22732259: parser error : Extra content at the end of the document
<backuptime>2015-04-14T08:31:4
                              ^
LTFS17037E XML parser: failed to read from XML stream
LTFS17016E Cannot parse index direct from medium
LTFS11194W Cannot read index: failed to read and parse XML data (-1014)

LTFS11257I No index found in the index partition
LTFS11220E Medium check failed: extra blocks detected. Run ltfsck.
LTFS11027E Cannot mount volume: medium consistency check failed
LTFS10023I LTFS volume information:
LTFS10031I Volume Name     : (null)
LTFS10024I Volser(Barcode) :
LTFS10025I Volume UUID     : 3fd4bdd3-2085-4b0c-9650-089fb44f4836
LTFS10026I Format Time     : 2015-04-14 01:13:16.204308140 CDT
LTFS10027I Block Size      : 524288
LTFS10028I Compression     : Enabled
LTFS10029I Index Partition : ID = a, SCSI Partition = 0
LTFS10030I Data Partition  : ID = b, SCSI Partition = 1

LTFS14013E Cannot mount the volume

[Jason_L]

Your post was a while back and perhaps you have already found a solution to your problem but...

From your screenshot it appears the LTFS filesystem has been found to contain inconsistencies.  I do not know to what extent your tape might be logically inconsistent, but you can run LTFSCK to see if it can be repaired. 

I refer you to the following HPE document that gives examples of different inconsistency scenarios and how these inconsistencies might be resolved by running LTFSCK.  Of course, there are no guarantees and it is possible that your tape cannot be recovered.

http://h20195.www2.hp.com/v2/getpdf.aspx/4AA5-1230ENW.pdf?ver=Rev%203

Recovery section starts on page 20 where there are different illustrations that describe how a LTFS can become inconsistent.  Also, starting on page 23 are examples of running the LTFSCK command and subsequent arguments that can be supplied.

Lastly, there is a lot of information available on LTFSCK (like the HPE document linked above) and on the web.  My last recommendation would be to research the LTFSCK command, how it works and make a determination if LTFSCK would be the best course of action for your overall situation or if you should pursue alternatives instead.