I have a brand new HP storageworks Ultrium 448 with LTO2 200/400 tapes and 100/200 LTO1 tapes. for the life of mew i can seem to get the compression any higher than 1:1. I have tried all compression options, hardware, and hardware if available then none.. i keep getting a capacity check error in the job log
Media CheckOnline media check : Insufficient online or nearline media is available to start job.Overwrite media check: There is no media online or nearline that can be overwritten or the job has been marked append/terminate.Media check status : Failed
What types of files are you backing up? mp3, jpg, 7z, zip files etc are already compressed and won't compress more. Doc, txt and database files can usually be compressed a lot.
A further thing that influences compression on tapes is if you have a slow PC, or the disks are slow, then the PC won't be able to supply the data fast enough to the tape drive to allow for compression. The tapes will try to run at full speed as it isn't good for the tapes to stop and wait for data, this would cause more wear and strain on the tapes and the drive, reducing their life cycle.
Im backing up word exel some audio and images as well as some videos. i completely understand that some types of file cant be compressed any further. all im trying to do is get the full capacity out of my tapes which used to work before the tape drive died.
Then it does look like the tape drive is too fast for the rest of the system, which just doesn't have time to compress the data fast enough for the tape.
You seem to be running a "test job". Don't rely on "Test Jobs" to determine capacity. I've seen them go wrong loads of times.
How much compression does software compression give you?
I guess you may have a bad tape drive. Any chance of getting it replaced? Or you could try flashing the firmware again. I've seen that cure a compression problem once.
well im not running backup-to-disk so i dont use software compression. and you are indeed correct on me using a test job, and i will see the results tonight from a job i have setup. i have just recieved a brand new one from hp which is the one im having problems with. im running the tapes and library diagnostic tool from HP and everything checks out. Health is 100%, tape is compatible with both LTO1 and LTO2 tapes that i have. it all seems to point to BE in my mind but i could be wrong. anything you guys need to see in order to better understand my situation?
I tried a regular job and it said that the tape ran out of space. so im guessing this time the test run was correct. is there anything else i should do?
