Howto backup directories with open files

[Roderick Derks]

Hi there,

Is there a way to backup directories on my Unix system while files are still in use?
I use Ignite to backup VG00. I want to backup some directories on VG01. But the files might be in use. I want to create a tar file.

What is the best way? Can I use Ignite, some other HP backup tool or a third party tool?

Greetz,
Roderick

[Steven E. Protter · Accepted solution]

Shalom Roderick,

To get clean copies of files that are open is a problem. There is always the risk when you go to restore that the file will not be usable.

HP DP 5.5, Veritas Netbackup and other third party vendors have proven software that can get clean copies of open files.

For database backups, you'll want an add on that lets you do hot backups.

I've heard that oracle databases can be put into backup mode and then backed up with simpler tools. I have yet to have a chance to test this.

SEP

[A. Clay Stephenson]

Unlike other unnamed OS's, UNIX with rare exceptions uses advisory file locking so that backups of files that are in use is not a problem. Tar, cpio, fbackup, and DataProtector do not check for the existence of locks on files or portions of files so that the backups will completely ignore any such locks. UNIX doesn't care how many processes have a particular file open.

However, just because a file can be read does not mean that you have a useful backup.
An example of a backup that might be perfectly accurate in that it represents each block original data as it was read but also perfectly useless - in that it cannot be used to restore a working system - is a backup of a running database. Special steps need to be taken to make such a backup both accurate and useful.

[Cem Tugrul]

Roderick,

As the 2 famous Gods mentioned
i also would not go for backup if some files are open or still in use.it is really risky
operation also if the files belong to DB
but on the other hand you can take online bcks with combination of rman for oracle db
According to me i think it is very important
to decide the right backup metod because
you can easily see many variants of backup/restore metodology.

Good Luck,

[Cem Tugrul]

Also would be helpful for you to have such
a kind of attachment.
Good Luck,

[James R. Ferguson]

Hi Roderick:

Adding to Clay's remarks, 'fbackup' is very useful in this regard.

'fbackup' computes a checksum for a file immediately before it transfers it from disk. At the completion of this transfer, the checksum is computed again from the disk image. If there is a difference in checksums the file has changed. 'fbackup' marks this copy of the file on tape as "bad" and proceeds to retry the copy 'maxretries' times.

When an attempt is made to restore a file with 'frecover' if an unchanged copy doesn't exist on the tape, nothing will be restored.

The default value of 'maxretries' is five (5). See the 'fbackup' manpages for more information.

Regards!

...JRF...

[Roderick Derks]

Thanks everyone for your info.
I'm gonna use Veritas. Seems to be the easiest solution for us.

[Roderick Derks]

Thanks everyone for your info.
I'm gonna use Veritas. Seems to be the easiest solution for us.

(Cem Tugrul: 4+4=8 :-) )

[Senthil Kumar .A_1]

Hi Rederick,

Seems like a very good discussion you guys had.

But dissapointed that no points were awarded for the suggestions I see that was worth more than a thousand words of a professional consultants.

These guys deserve to be be awarded some points. Please consider.


Regards,
Senthil Kumar .A

[Roderick Derks]

I see something went wrong, I added the points again. Thanks.

[AshishJain_USA]

Hi Roderick

If u plan to use Veritas Netbackup for this ( and u have an Oracle Database to backup ), you will stll have to use the Oracle RMAN to get consistent copies.

rgds...Ashish