How to view files from a tape?

DimTheo · 11-11-2016, 11:56 AM

Hello

I have been backing up some files to a tape like this :

tar cvf - *many files here* | ssh root@192.168.1.2 dd of=/dev/rmt/1 obs=126b

the tape device is mounted on a solaris system

the tar process completes always fine with no errors but when i ssh into the solaris and try to view the files by typing tar tvf /dev/rmt/1 i get a tar : tape error

can you help? thanks

rknichols · 11-11-2016, 12:06 PM

You have to read the tape at the same block size used to write it.

Code:

tar -b 126 -tvf /dev/rmt/1

jefro · 11-11-2016, 06:59 PM

Wonder if you have to rewind it or set it to index.

https://docs.oracle.com/cd/E23824_01...efiles-30.html has some info.

DimTheo · 11-12-2016, 04:51 AM

Quote:

Originally Posted by rknichols

You have to read the tape at the same block size used to write it.

Code:

tar -b 126 -tvf /dev/rmt/1

hi

i still get the same errors

tar -b 126 -tvf /dev/rmt/1
tells me how i syntax tar

tar -tvf /dev/rmt/1 -b 126
tar: /dev/rmt/1: I/O error

any others tips please?

pan64 · 11-12-2016, 05:04 AM

probably the tape device was not rewound at the beginning. I don't know how did you take care about the position of the tape at all.

MadeInGermany · 11-12-2016, 08:03 AM

Maybe you must read the tape with the reverse command?

Code:

dd if=/dev/rmt/1 ibs=126b | tar tvf -

Get the tape status with

Code:

mt /dev/rmt/1 status

Explicitly rewind the tape with

Code:

mt /dev/rmt/1 rewind

DimTheo · 11-16-2016, 05:15 AM

thank you i got it to work with dd if=/dev/rmt/1 ibs=126b | tar tvf -

now i would like to copy all data from that tape to a local folder which i have already cd to
Would the command be

tar xvf - . | ssh root@192.168.1.2 dd of=/dev/rmt/1 obs=126b ?

thanks

pan64 · 11-16-2016, 05:20 AM

reverse order:
ssh root@192.168.1.2 dd of=/dev/rmt/1 obs=126b | tar xvf -

DimTheo · 11-16-2016, 05:28 AM

thanks
seems to be working

pan64 · 11-16-2016, 05:31 AM

sorry, I missed an important point:
sh root@192.168.1.2 dd if=/dev/rmt/1 obs=126b | tar xvf -
do not use the previous one, that may overwrite your tape!

DimTheo · 11-16-2016, 05:40 AM

hhmm i get these

ssh root@192.168.1.2 dd if=/dev/rmt/1 obs=126b | tar xvf -
Password:
read: Not enough space
0+0 records in
0+0 records out
tar: This does not look like a tar archive
tar: Error exit delayed from previous errors

pan64 · 11-16-2016, 05:59 AM

probably you need to rewind the tape before

DimTheo · 11-16-2016, 06:01 AM

i did , but no luck

mt -f /dev/rmt/1 rewind
bash-2.05# exit

ssh root@192.168.1.2 dd if=/dev/rmt/1 obs=126b | tar xvf -
Password:
read: Not enough space
0+0 records in
0+0 records out
tar: This does not look like a tar archive
tar: Error exit delayed from previous errors

pan64 · 11-16-2016, 06:06 AM

in post #7 you told it is working. Probably the content on the tape is now damaged, you need to rewrite it first.

DimTheo · 11-16-2016, 06:08 AM

trut , with dd if
but you told me to use dd if

with if it craps out
with of , it s ok

should i use dd if or dd of ?