cpio not seeing EOT

[VINCENT SPURGEON]

I have DAT drive that I'm attempting to back some large amount of data to: over 36GB. I want each file to be seperated by a tape mark, so I'm using a no-rewind tape device node.

I created a test script to simulate my problem. My TEST_FILE is over 700 GB.

As a test, whenever I run:


TAPE=/dev/rmt/0mnb
while [ ${CT:=0} -lt 200 ]
do
((CT=${CT}+1))
echo ${TEST_FILE} | cpio -ocvB > ${TAPE}
done

I never get end of archive message or an error and I'm quite sure that the data is not getting overwritten, but when I execute:

TAPE=/dev/rmt/0mnb
while [ ${CT:=0} -lt 200 ]
do
((CT=${CT}+1))
echo ${TEST_FILE}
done | cpio -ocvB > ${TAPE}

I do get prompted for the next tape.

Any ideas on what is going on here?

[Dan Hetzel · Accepted solution]

Hi,

This is probably stupid, but are you sure
that between your writes to the no-rewind
device and your reads to the same no-rewind,
you are effectively rewinding the tape???

Otherwise, you won't have much to read...

;-)


Dan

[VINCENT SPURGEON]

Well, I'm assuming that "0mnB" is no-rewind berkley. maybe it's not defined properly, eh?

[VINCENT SPURGEON]

before executing the script, I can:

echo "this is the beginning..." > /dev/rmt/0mnb

run the script then issue a "mt -f /dev/rmt/0mnb rewind";
cat /dev/rmt/0mnb
and still see "this is the beginning...".
then I can cpio -ivt < /dev/rmt/0mnb to see each tape mark.

[VINCENT SPURGEON]

Here's more information...

# ioscan -fnC tape
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
tape 0 0/0/1/0.3.0 stape CLAIMED DEVICE ARCHIVE Python 04687-XX
/dev/rmt/0m /dev/rmt/c0t3d0BESTn
/dev/rmt/0mb /dev/rmt/c0t3d0BESTnb
/dev/rmt/0mn /dev/rmt/c0t3d0DDS
/dev/rmt/0mnb /dev/rmt/c0t3d0DDSb
/dev/rmt/c0t3d0BEST /dev/rmt/c0t3d0DDSn
/dev/rmt/c0t3d0BESTb /dev/rmt/c0t3d0DDSnb
# ls -l 0m*
crw-rw-rw- 2 bin bin 205 0x003000 Oct 23 10:39 0m
crw-rw-rw- 2 bin bin 205 0x003080 Oct 23 10:54 0mb
crw-rw-rw- 2 bin bin 205 0x003040 Nov 6 12:53 0mn
crw-rw-rw- 2 bin bin 205 0x0030c0 Oct 23 16:18 0mnb
#

[VINCENT SPURGEON]

The above test file is 700 MB not GB...