Do i need to use LVM

Hi,

I am installing Suse 10.2 for zSeries. I have allocated 3 3390 disk drives at 6.8GB each.
I plan on using one drive for swap space so that will leave 13.6 for SUSE. With this much space should i still use LVM. Also is there any good instructions on how to configure GDM. I am a zOS system programmer and i have been directed to move our oracle database off Sun 20K servers onto the IBM Z series mainframe due all the server and dasd problems the Sun 20K’s have been having. So i am new at this stuff.

LVM is useful if you intend to join up multiple physical volumes into one logical volume. The overhead is small. 6G sounds like a lot to devote to swap space. Maybe you could join all three volumes into one big 18G volume, then allocate a swapfile for swap. That would gain you more space.

GDM - as in Gnome Display Manager? Or?

Re the LVM question.

As you are in the enterprise market, I would say you do need LVM.
It basically allows you to manage your DASD in fairly flexible ways. I use OpenSuse on my on PC, and so don’t need the resize volumes or even have mirroring. However, you will need these features, mirroring probably now (not just for your root volumes, but for your data volumes), and extending volumes sometime in the future, unless your databases are really very legacy and so are static.

I would recommend a review of your requirements. With Unix you will need 1.5-2x your memory as swap, I know you want to avoid swapping with Oracle, but O/S like to RESERVE swap in case. Is 3GB correct for this? How big are your database(s)? What type of DASD is being provided (RAID1/RAID5 etc) this may answer the question do you need to LVM to provide your data resilience.

I can’t even begin to answer your GDM question, but I would imaging that you would be using a remote X desktop, so your question might be “how do I start an X desktop using my XVY software?”

Running Linux on a mainframe - wow!

Along the lines of what KaptRoger is saying I agree LVM brings you volume flexibility.
Also functions like volume snapshots and the ability to easily create and restore volume dumps can be very handy in a server environment.

As for the desktop or home server use… I don’t see that much benefit there (personal observation), as you generally set things up once and can easily shift around when needed.

In any case I would not recommend spanning a volume across multiple disks unless you do create some form of mirroring or raid setup (preferably raid by hardware). If one of your disks fails and you’re not running with such a safeguard, big chance all data will be lost.

By 10.2… do you mean SLES 10 SP2 or openSUSE 10.2? If it’s the later you might want to consider openSUSE 11.1?

Cheers,
Wj

I can totally agree with that, I have a home server setup with eight HDDs making 3TB in an LVM; ONE of the disks went faulty last night during a write operation, it looks like I may have lost all the data on their (although it may be recoverable) - I Don’t have a backup of my important data (photos, spreadsheets etc) so I am looking at the prospect of loosing many years of files etc.

BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!! BACKUP YOUR DATA!!!

By the way, I choose LVM as I am constantly needing more disk space and the inconvenience of having to move files around the network or from one disk to a bigger disk was too much. An LVM allows me to add new disks at will without all that hassle.