re-install the OS

[addendum]

I hv a RH EL installed in the server , but it seems have some system problem , I want to re-install it , but just want to overwrite the system program , not to format the system before install it ( because there are some data in the server ) , is it possible to overwrite the system only but not lost the data ? I know windows can , how about RH ? thx

[Robert Walker_8]

HI,

We have done this in the past - it should be simply a matter of not reformatting some of your partitions (eg /home, /whatever).

When you put your cds in and reboot redhat will detect that you have an existing implmentation, and should be given the option to upgrade or re-install.

When selecting re-install as you go to disk druid select only the partitions that you want to re-install (eg /, /boot, /usr, /var) for the others there is an option to place entries in /etc/fstab but not to reformat them for those that you wish to reinstall it is probably be best to reformat them.

Of course if all you have is / and data is in there as well as the os then you will have to either back it up (tar, gzip, cp, etc) or copy it to somewhere else before you begin.

I have done this sort of process on an Oracle server without problems. I would imagine the upgrade process would work as well, but if the problem is in a config file this may not get resolved.

It is also probably advisable to backup the server prior to any work done - we have used ghost in the past and this has worked well, but there are other products that should be able to do the job just as well.

Robert.

[Ivan Ferreira]

You can, but complete re-install (windows style) it not the way to go to solve the problem. You can use rpm -V to verify the consistence of the packages. Also, instead reinstalling, you should upgrade the system using red hat network.

[Rick Garland]

Make sure you have the correct sizes and all the allocations. Can get this with "fdisk -l' as this will provide the info.

When doing the reinstall, partition the disk as it was but you are only going to format the OS partitions. The non-OS partitions you do not need to partition.