Solved

how to copy tape content to disk

Posted on 2003-11-07
12
1,080 Views
Last Modified: 2013-12-27
I first use "tar xvf /dev/rmt/n", but system prompts wrong block size 1844. Also I tried using "cpio" command, but system said "I/O error, 0+0 input, 0+0 output".
Then I use "dd if=/dev/rmt/n of=/tmp/tapetest bs=10k count=1", then "file tapetest", the result is "ascii text".
How can I copy the content of the tape to disk? Thanks.
0
Comment
Question by:frog77
  • 6
  • 3
  • 2
  • +1
12 Comments
 
LVL 24

Expert Comment

by:shivsa
ID: 9704144
use tape tool

To correct the block size, choose Block I/O from the Tape Tool Properties window. In the text field that appears, type the correct block size (the one from the tape).

.
0
 
LVL 24

Expert Comment

by:shivsa
ID: 9704216
also to check tape device and all, man mt.

0
 
LVL 24

Expert Comment

by:shivsa
ID: 9704233
First check that the tape is readable  by Solaris. Use the "tcopy" command to check if you can see blocks and sizes, with this information retry your command. Try also using 20b as the block size.
man tcopy
0
 
LVL 24

Expert Comment

by:shivsa
ID: 9704240
i just noticed what r u using for /dev/rmt/n, i think u should be using /dev/rmt/0 or somethine whatever is there in /dev//rmt configured.
0
 
LVL 40

Expert Comment

by:jlevie
ID: 9710179
To get the data off of the tape you need to know what mechanism (tar, cpio, dump/ufsdump, etc) was used to write the tape and whether the data might be byte-swapped w/respect to  Solaris, i.e., what OS wrote the tape. There are a lot of ways on placing data on tape and you won't be able to recover the data unless you use a complementary reading tool.
0
 

Author Comment

by:frog77
ID: 9710681
Thanks, jlevie. The problem is I do not know how the data are written to tapes. The previous S.A. has gone. Are there any command to see what way of the data are previously put into the tape? Thanks.
0
Do You Know the 4 Main Threat Actor Types?

Do you know the main threat actor types? Most attackers fall into one of four categories, each with their own favored tactics, techniques, and procedures.

 
LVL 40

Expert Comment

by:jlevie
ID: 9714895
Were these tapes written on a Sun? If so the obvious choices would be tar, cpio, or ufsdump. Since you've tried tar & cpio with no luck I'd suggest trying 'ufsrestore if /dev/rmt/?' and see if that works.
0
 

Author Comment

by:frog77
ID: 9715983
I guess tapes were written on Sun. But I've already tried "ufsrestore" command. The system prompts that wrong block size. I've no idea how to make it work.
Thank you.
0
 
LVL 40

Accepted Solution

by:
jlevie earned 75 total points
ID: 9717453
Since none of the standard (tar, cpio, ufsdump) methods work it would seem to me that you might be looking at a tape written:

1) In some proprietary backup format (Networker, Veritas, ArcServe, etc)
2) On something other than a unix system with a native tool (NT backup, etc)
3) Via some non-standard method (user program, dd direct to raw tape, etc)

In all of those cases I'd say that you'll have to find out from the previous SA how the tape was written to be able to read it. Of course it is also possible that the tape was orginally written with a standard mechanism and has been damaged or has gone bad. Knowing what should work would probably answer that question.
0
 
LVL 24

Expert Comment

by:shivsa
ID: 9717556
please read man page for mt.
and take all the information from tape.

did u read man page for tcopy also. it might be useful determining these information.
0
 

Expert Comment

by:sagar24
ID: 9730809
hi
I am not sure but try using any one file from the directory
/dev/rst/ ..just try any file which identifies the tape device you are using

sagar
0
 
LVL 24

Expert Comment

by:shivsa
ID: 9734153
u can try to set density to 0 and then try to read the tapes.
mt -f /dev/rmt/n setdensity 0

it will be slower but it will automatically adjusted to default block size.
0

Featured Post

Find Ransomware Secrets With All-Source Analysis

Ransomware has become a major concern for organizations; its prevalence has grown due to past successes achieved by threat actors. While each ransomware variant is different, we’ve seen some common tactics and trends used among the authors of the malware.

Join & Write a Comment

Let's say you need to move the data of a file system from one partition to another. This generally involves dismounting the file system, backing it up to tapes, and restoring it to a new partition. You may also copy the file system from one place to…
My previous tech tip, Installing the Solaris OS From the Flash Archive On a Tape (http://www.experts-exchange.com/articles/OS/Unix/Solaris/Installing-the-Solaris-OS-From-the-Flash-Archive-on-a-Tape.html), discussed installing the Solaris Operating S…
Learn several ways to interact with files and get file information from the bash shell. ls lists the contents of a directory: Using the -a flag displays hidden files: Using the -l flag formats the output in a long list: The file command gives us mor…
Learn how to get help with Linux/Unix bash shell commands. Use help to read help documents for built in bash shell commands.: Use man to interface with the online reference manuals for shell commands.: Use man to search man pages for unknown command…

746 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now