Database backup

[Manoj Misra]

Hi,

I am looking some help on DD command. I want to backup multiple device files on a single tape. For example..

/dev/vg01/rsystem01
/dev/vg01/rrbs01
/dev/vg02/rshort_msg01
/dev/vg03/rshort_msg02

I want to use DD command and copy on a single tape. I am wondering that if I would issue the command one by one could cause over write the previouse one.

Thank you,

Manoj

[Luc Bussieres_1 · Accepted solution]

Manoj,

If you don't want to overwrite the previous dd you could use the no-rewind device (/dev/rmt/0mn for example note the n at the end of the device mean no-rewind) this way each of your dd will be appended to the tape:

dd if=/dev/vg01/rsystem01 of=/dev/rmt/0mn
dd if=/dev/vg01/rrbs01 of=/dev/rmt/omn
...

Regards
Luc

[Luc Bussieres_1]

Ooops there was a typo in the second dd command I have givent you it should have been :

dd if=/dev/vg01/rrbs01 of=/dev/rmt/0mn

I have put an o instead of a 0

Luc

[Sanjay_6]

Hi,

AS suggested, use the no rewind device file (omn). Before backup reten the tape using the mt command (do man mt) for more help.

First Reten tape
dd first file using no rewind device
dd second file using no rewind device
....
...
Reten tape

Hope this helps.

Regds

[Rothery Harris]

Dear Manoj,

Is there any particular reason you wish to perform a dd? Is it because you database uses raw (uncooked) disk. The previous replies are quite write is suggesting that a no rewind device file will do the trick.

Rothery Harris