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sej7278
30th March 2006, 09:40 AM
As I ready myself for installing FC5 on a few machines, I'm thinking about disk structure.

One machine has 2x200gb which currently on FC4 is one disk for /boot, /, swap and another disk for /data, which means that most of the first 200gb is wasted, as i don't think i could ever install 200gb worth of programs, and the 2nd disk is full of mpegs etc.

If I LVM'd them, it would basically create a 400gb root.

a couple of questions:

1. if one of the lvm'd disks fails, would that kill the entire volume?

2. is lvm like software raid?

3. when fc6 comes out and i want to reinstall (don't like upgrade installs) how would that work - would i be able to specify which parts of the lvm to overwrite (e.g. /boot, swap, /, /home, but not /data)

i'm wondering if i might be better off getting a cheap 80gb ide drive for /boot, swap, /root etc. and then just putting the 2x200gb as /data1 and /data2 without lvm.

SlowJet
30th March 2006, 10:41 AM
You can install FC5 and FC6 on the first disk and have plenty of room for a shared home ot individual home.
Then use the second drive for date on a PV/VG with LV's as needed or one big lv.

hda1 - ext3 /boot FC5 200 mb
hda2 -ext3 /boot FC6 200 mb (just make the partiton for now)
hda3 pv/vgFCrealease 37GB - lv's / 18GB, /home 16GB, /swap 1 GB
hda4 - extended
hda5 pv/vgFCdevelopment 37GB - lv's /18GB, /home 16GB, /swap 1 GB
hda 6, 7, 8 as needed

hdb1 pv/vg full drive - lvmydata 100GB ext3 - /mydata , lvfuture 16GB /mydata2, ...

SJ

sej7278
30th March 2006, 01:48 PM
but if you have an lv spread across sda and sdb, then sdb died (or i installed fc6 over fc5) would that screw up the whole volume?

i'm thinking of 2x200gb drives:

sda1 - ext3 /boot 200mb
sda2 - 1gb swap
sda3 and sdb1 398gb / (root) as LVM

SlowJet
30th March 2006, 02:17 PM
I think the stringing of physical volumes together is more about large server volume management than effient partitioning schemes.
On a large server, a volume of a volume group can be moved to another volume and the chanin updated so the old volume can be changed out preemptively.

All I can say about data management is that it should be seperated by type, use, and vollitility inaccordance with backup and recovery plans to prevent down time and data loass.

SJ

markkuk
30th March 2006, 04:28 PM
One machine has 2x200gb which currently on FC4 is one disk for /boot, /, swap and another disk for /data, which means that most of the first 200gb is wasted, as i don't think i could ever install 200gb worth of programs, and the 2nd disk is full of mpegs etc.

If I LVM'd them, it would basically create a 400gb root.
No, it would create a 400GB LVM volume group. Using all of that for root logical volume would be a bad idea.



1. if one of the lvm'd disks fails, would that kill the entire volume?

2. is lvm like software raid?

3. when fc6 comes out and i want to reinstall (don't like upgrade installs) how would that work - would i be able to specify which parts of the lvm to overwrite (e.g. /boot, swap, /, /home, but not /data)

1. Yes
2. No.
3. Define parts that you want to keep as separate logical volumes, instead of putting everything in /.

sej7278
30th March 2006, 07:25 PM
right thanks, i think i'm entirely missing the point of LVM here!

so what would you recommend i do with 2x200gb drives, i'd certainly want both disks to be independent of each other - i don't trust hard drives not to fail, which is why i've never used raid, but i don't want to waste a whole 200gb drive on just programs and i'm not a fan of putting much data in /home, i prefer a seperate partition.

i'm really thinking of the 80gb boot drive and 2x200gb /data1 and /data2 drives and forgetting the LVM stuff :(