Redhat Linux server "Clone/Mirror/Backup", HOW ?

[M.G.Chandra Babu]

We are using Redhat linux server with PHP,MYSQL. Now I want to Clone all the data in to another HDD (Clone or Mirror). I can do a archive by using "TAR" command, But I want to do this without shut down the database. Now the HDD already connected to our machine. IS IT POSSIBLE VIRTUALLY DO A BACKUP WITHOUT SHUTDOWN ANYTHING ? WHAT THE BEST WAY OR COMMAND TO DO THIS ?

[Marcin Golembski_1]

If the logical geometry of both disks is the same concerning the numbers of heads and sectors, and the number of cylinders on the target disk is equal or greater than on the source (check it all in fdisk), then I would try dd, e.g.:

dd if=/dev/hda of=/dev/hdb bs=xxxxx

xxxxx being the number of sectors times 512.

[Bruno Cunha]

Hi, without shutting down the DB you cannot garanty the integrity of the data. If you don't want to shutdown anything there are agents, for example from Veritas Netbackup, that do online backups, but are expensive. The other way is to shutdown the database, do a "mirror", broke the mirror, restart the DB and do the backup of the mirror created.