2 queries

[Chris St. Pierre]

Please don't hijack other threads.

On Tue, 15 May 2007, sylvan dacounha wrote:

>  1) i have a REDhat 9 server . i need to upgrade it with CENTOS OS  cd i upgrade to CENTOS without loosing any data
>  i have separate partions .. i dont wanna harm the data n var partitions but my / , /root , /usr , /opt, /usr/local ..

Not possible.  RH9 is old old old; if there was an upgrade path, you'd
have to go through about a billion intermediate steps and would accrue
an incredible amount of cruft in the process.  Backup and reinstall.

>  2) cd i make a disk ghost of my redhat linux HDD so i can make HDD and keep it as spare and if the working HDD fails i jus replace with the ghost HDD swich the machine ON aand its up and running
>  this machine will be used as a DNS Server only so data not problem

Put both disks in the machine and boot off a rescue CD.  Assuming your
master is /dev/hda and your spare is /dev/hdb, you should be able to
do:

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

Note that the drives must be _identical_ for that to work.

The better solution is to use kickstart and configuration management
(Cfengine, Puppet, bcfg2, etc.) to ensure that you have a fully
replicatable build process and keep things identical and replicatable
from the beginning, rather than trying to bolt on redundancy later.
When a hard drive dies in one of our machines, we just install a new
one and rebuild from bare metal; it takes us about 20-30 minutes most
of the time.

Chris St. Pierre
Unix Systems Administrator
Nebraska Wesleyan University
----------------------------
LOPSA Sysadmin Days: Professional Training for Professional SysAdmins
August 6-7, Cherry Hill, NJ
http://lopsa.org/SysadminDays