On Thursday, 16 May 2013 at 19:56:14 -0400, Zaphod Beeblebrox wrote: > On Thu, May 16, 2013 at 5:08 PM, Bob Bishop <r...@gid.co.uk> wrote: >> On 16 May 2013, at 21:51, Zaphod Beeblebrox wrote: >> >>> I have to retrieve some very old backups. They were made on FreeBSD and >>> are on tape... specifically DDS4. [etc] >>> However, attached to either controller (after a reboot of the machine >> and a >>> powercycle of the drive), I get: >>> >>> [1:25:325]root@run:/home/foo> dd if=/dev/sa0 of=tape5 >>> dd: /dev/sa0: Input/output error >>> 0+0 records in >>> 0+0 records out >>> 0 bytes transferred in 0.002930 secs (0 bytes/sec) >>> >>> ... which is a return code of '1' and no messages on the console... >>> >>> I have, before you ask, tried "bs=10k" and 20k ... but I believe this >>> command should run by itself fetching the first 512 bytes of each block >> --- >>> narrowing down the block size logically comes after making the tape go. >> >> >> Try bs=64k > > Same result. Besides, as far as I understand, the proper operation > (if the blocksize is too small) is to read the first $n bytes and > then write them to the output..
The obvious question: can you write tapes and read them back? My experience with DDS tapes was of extreme unreliability. The age doesn't make things any easier. Greg -- Sent from my desktop computer. Finger g...@freebsd.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua
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