07-04-2009
First off, (depending on the type of your tape drive) you have a pretty good chance of not needing any compress at all because most of the IBM tape drives have a hardware compression built in. If you send a compressed stream down to the tape drive it will be compressed a second time which will usually make the file a little bigger (because of the second compression overhead adding), not smaller.
Second, even if it is justified to use "compress" in your case, you probably have to add "if=-" to the "dd" command. AFAIK "dd" doesn't use stdin per default for incoming data. It also might be necessary to state the blocksize. Use "bs=<some number>" in this case to state the block size in bytes.
A third reason might be that you have to adress the tape drive with another device number, maybe "/dev/rmt0.1". Have a look in the manual for the meaning of the minor device numbers with tape drives.
I do not recognize your first statement "change tape block_size=512", usually this is accomplished using the "tctl" command, alternatively use the "chdev" command on "/dev/rmtn".
I hope this helps.
bakunin
Last edited by bakunin; 07-07-2009 at 09:41 PM..
Reason: edited typos
10 More Discussions You Might Find Interesting
1. AIX
Hello all,
Anyboby knows what is the reason by which the ouput of the command mt -f /dev/rmt0.1 status on AIX does not show the same information that in the rest of platforms UNIX (Solaris, HP-UX, ...)?
Then, what command of AIX is similar to mt- f /dev/rmt0.1 status of Solaris? We need it to... (0 Replies)
Discussion started by: smoraprosol
0 Replies
2. Solaris
Hi, Anyone can help
My solaris 8 system has the following
/dev/null , /dev/tty and /dev/console
All permission are lrwxrwxrwx
Can this be change to a non-world write ??
any impact ?? (12 Replies)
Discussion started by: civic2005
12 Replies
3. AIX
I am trying to find a way to do the following on an AIX 4.2 with Korn:
tar cvfpdl - . | compress > /dev/rmt0
The /dev/rmt0 is the device we use when we tar directly to it.
I want to compress a folder's content to tape. Our current TAR does not have compression at all. We only have... (5 Replies)
Discussion started by: Browser_ice
5 Replies
4. AIX
I only about the principle of filesystems from the very basics on Linux and Windows. But I want to know if it is possible on an AIX 4.2 to create one NFS on a server which is pointing to a tape drive (/dev/rmt0) of another server ?
This is because we several backups to do on a 5 servers that... (5 Replies)
Discussion started by: Browser_ice
5 Replies
5. UNIX for Dummies Questions & Answers
Hi folks,
Here i have written a shell script to calculate a maximum number from 10 numbers entered on command line.
max=0
echo Enter 10 numbers , one at a time
for i in 1 2 3 4 5 6 7 8 9 10
do
read n
max=`expr $max + $n`
if --- At this last step there is some problem, it gives error... (5 Replies)
Discussion started by: rits
5 Replies
6. AIX
rmt0 allows get increased .. !
I have faced this issue in my AIX server, rmt0 allows get increased and it's filled /root till 100%
There is no tape in tape drive why it's increased?
Pls advice.. (1 Reply)
Discussion started by: Mr.AIX
1 Replies
7. Homework & Coursework Questions
Creating a large number of rules such as 100000, iptables will produce errors after 42000 rules "iptables: Unknown error 18446744073709551615".
But another machine where i have debian virtual machine I can easily run the sciprt of 100000 of rules
I am waiting for your reply
4.... (1 Reply)
Discussion started by: tahirfattani
1 Replies
8. AIX
Dear all
First of all, my English not so good.
We have p52a (production server) and p52a (test server). Tape drives are VXA2.
When both servers were AIX 5.3, mksysb on production server and restoring to test server was OK.
The production server was AIX 5.3 and recently upgraded to... (3 Replies)
Discussion started by: fifa15pc
3 Replies
9. Shell Programming and Scripting
Objective: To recreate the partitioning setup of /dev/sda on /dev/sdc
How would I parse the below information and initialize variables
(an array?) that can be used to build sgdisk commands in a script, regardless of the number of partitions?
Something along the lines of:
sgdisk -n... (12 Replies)
Discussion started by: RogerBaran
12 Replies
10. AIX
The company I work for has various AIX servers that I've recently migrated to AIX 7.1 (from 6.1). Some are powerHA clusters some are not. Likewise, the systems engineer that I replaced had net-snmp installed on said clustered systems. Long story short I am re-invoking AIX's native SNMP (v3) for... (1 Reply)
Discussion started by: davix
1 Replies
tcopy(1) User Commands tcopy(1)
NAME
tcopy - copy a magnetic tape
SYNOPSIS
tcopy source [destination]
DESCRIPTION
The tcopy utility copies the magnetic tape mounted on the tape drive specified by the source argument. The only assumption made about the
contents of a tape is that there are two tape marks at the end.
When only a source drive is specified, tcopy scans the tape, and displays information about the sizes of records and tape files. If a des-
tination is specified, tcopy makes a copies the source tape onto the destination tape, with blocking preserved. As it copies, tcopy pro-
duces the same output as it does when only scanning a tape.
The tcopy utility requires the use of Berkeley-compatible device names. For example,
example% tcopy /dev/rmt/1b /dev/rmt/2b
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWesu |
+-----------------------------+-----------------------------+
SEE ALSO
mt(1), ioctl(2), attributes(5)
NOTES
tcopy will only run on systems supporting an associated set of ioctl(2) requests.
SunOS 5.10 10 Mar 2000 tcopy(1)