AIX

Dear Guy’s
By using dd command or any strong command, I’d like to copy huge data from file system to another file system


Sours File system: /sfsapp
File system has 250 GB of data
Target File system: /tgtapp


I’d like to copy all these files and directories from /sfsapp to /tgtapp as file system copy by using strong command



Pls your advice..

I suppose you want to preserve absolutely everything: files, ownerships, filemodes, ...

I do that (out of habit - presumably there are other equally good ways to do it) using two tar's and a pipeline:

Code:

# cd /path/to/sourcedir
# tar -cf - . | (cd /path/to/targetdir ; tar -xf - )

The first tar packs everything to <stdout>, the second one unpacks from <stdin>, this is what the "-" stands for. If you include a "-v" to one tars options you can even watch the progress (at a small expense of performance of course).

I hope this helps.

bakunin

So my command should to be like this ...

PHP Code:

 
cd /sfsapp
tar -cf - . | (cd /tgtapp ; tar -xf - ) 


---------- Post updated at 07:17 AM ---------- Previous update was at 07:10 AM ----------

But the number of the files is very huge .. Are you sure this is will success ?

Yes, this will work, regardless of the number of files.

You could use "dd" too, but i would prefer to use an "high-level" approach when possible instead of a "low-level" approach such as "dd". With "dd" it is easily possible to overwrite not only files, but devices, volume group information, things quite vital to your system.

With "tar" you deal with files, directories and the like - things which are easily recognized by you. With "dd" you ultimately deal with devices, which is much more dangerous. If you mistype "/tgtpaath" in the above mentioned "tar" command you will run into a "disk full"-error, have the chance to correct it and start over. If you confuse hdisk127 and hdisk126 in a dd command it will work well but probably destroy data you didn't want to lose.

That doesn't mean at all that "dd" is a bad tool - it is very powerful, but the power comes at the price of being dangerous too. Use it when you need it, not when it is possible, is my principle. Maybe i'm feeble, but i have been working as a Sysadmin for a long time and i am still alive. ;-))

I hope this helps.

bakunin

How about using the backup and restore commands?

Are /sfsapp and /tgtapp mountpoints?
Is there anything in /tgtapp already?
Though you don't mention the version of AIX or anything about the hardware of the disc system, do you have an AIX version which can deal with files larger than 2 Gb ?

The usual solution is to use "find" piped to "cpio -p" .
e.g.

Code:

cd /sfsapp
find . -xdev -print | cpio -pdumv /tgtapp