SUMMARY: Thanks to all who responded with your suggestions. Many of you suggested using dd which I had previously tried but the results were unfruitful. I believe I have a tape that can not be read with my drive and version of o/s as some of you suggested. I found another tape with the data sought and Darren Dunham of Taos - The SysAdmin Company hit my solution needed. Darren provided me some insight on how to determine what command wrote the tape records by analyzing the dd output in octal. Darren wrote: Ignore the format and see if you can read anything at all useful from it. Does this get anything? % mt -f /dev/rmt/0n rewind % dd if=/dev/rmt/0n of=/tmp/data bs=64k count=2 If it does, show me this.. % od -c /tmp/data | head This resulted: 0000000 \0 \0 \0 001 7 263 \n 261 \0 \0 \0 \0 \0 \0 \0 001 0000020 \0 \0 \0 \0 \0 017 204 377 \0 \0 352 l e 346 327 0000040 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 Darren continues: Gotcha. That's definitely a UFS dump tape. The \0 \0 352 l beginning at position 24 is indicative of ufsdump. Now that you can read the bits, lets see if we can get restore to recognize it. Try this.. (rewind tape) dd if=/dev/rmt/0n ibs=64k | ufsrestore if - If you get a restore> prompt, you can do a 'ls' and 'cd' to look around at the data that should be on the tape. MORE SUMMARY: Larye D. Parkins suggested that the tape maybe deteriorated beyond recovery. Larye wrote: Even with semi-modern technology, magnetic tape is ephemera: the shelf-life of a tape is probably about two years, maybe less (my hunch/guess based on 40+ years of industry experience with computer and audio tapes). The problem is the same magnetic characteristics that make it possible to write on the tape in the first place doom it to a certain half-life, as the magnetic domains on the tape gradually randomize themselves. The adhesive matrix that bonds the magnetic particles onto the substrate (plastic tape) also has a shelf-life. One of the big problems with older tapes is loose oxide, which is most certainly randomly oriented once it flakes off the tape: try cleaning the tape, if you have a tape cleaner (they used to make them for reel-to-reel tapes, but I haven't ever seen one for cartridges: the drives may have cleaning blades built-in) or fast-forward to end-of-tape, rewind, eject, then clean the drive, try to read the tape, repeat up to three times. But, with an eight-year-old tape, it is possible that the domains have just faded out so the signal level is too low to read. Those old Exabyte 8-tracks were also very adjustment-sensitive: it wasn't uncommon to have a drive that could read tapes it had written, but the tapes couldn't be read on any other [otherwise identical] drive. In the really bad old days of reel-to-reel tape, I remember at least once using the tape we were trying to recover as an alignment tape to misadjust the drive we were using to match the one it had been written on. -- Thanks all for your quick replies ORIGNINAL POSTING: Hi all, I have a 1995 8mm 112M tape I am assured it is a dump tape. I have no other details. I assume it was written on a Sun4OS. I have had no luck reading this tape on my Exabyte EXB-8500 installed on my Solaris9 Ultra 10. The best response to all that I have tried is: ufsrestore ibf 126 /dev/rmt/0n Read error while trying to set up volume Continue? [yn] y Volume is not in dump format Any ideas? Also I have a tar format 8mm tape of the same data set but that has not proved readable either. Randy Doty BOEING IT UNIX Administrator *Phone: (253) 773-9419 *Email: randall.w.doty@boeing.com _______________________________________________ sunmanagers mailing list sunmanagers@sunmanagers.org http://www.sunmanagers.org/mailman/listinfo/sunmanagers _______________________________________________ sunmanagers mailing list sunmanagers@sunmanagers.org http://www.sunmanagers.org/mailman/listinfo/sunmanagersReceived on Thu May 22 17:04:05 2003
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