Does mounting 2 drives to one point give the raid effect

joshuarowley · 01-08-2006, 10:29 AM

Hi,

If i had 3 IDE hard drives in my compuer, one for linux, and 2 (of the same size) Could i mount them both to the same place to give one directory with twice the available space rather than putting half my stuff in one folder, and half in the other.

Cheers! Josh

Lenard · 01-08-2006, 10:51 AM

No....

When you mount the second drive the second drive is available and the first is not. Once you unmount the second drive the first will be available again.

Simple test for you, mount the first drive to a mountpoint and have a look at the directory structure (if any). Copy some file to this mountpoint and look again. Now mount the second drive to the same mountpoint, the file you just copied should vanish. Unmounting the second drive will 'magically' cause the file to reappear.

You want to look into LVM instead;
http://www.tldp.org/HOWTO/LVM-HOWTO/

joshuarowley · 01-08-2006, 12:24 PM

Thanks, that is helpfull.
I guess i could just buy a raid card... Are most compattible with Linux?
Thanks in advance

Lenard · 01-08-2006, 12:34 PM

Have a look on this site here;

http://www.linuxquestions.org/hcl/index.php/cat/201

Choose one that fits your distribution / pocket book best.

phil.d.g · 01-08-2006, 12:57 PM

You could also use a software raid - http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html

joshuarowley · 01-09-2006, 07:09 AM

Thanks everyone, Helpful information!

carl0ski · 01-09-2006, 08:52 AM

Quote:

Originally Posted by Lenard

No....

When you mount the second drive the second drive is available and the first is not. Once you unmount the second drive the first will be available again.

Simple test for you, mount the first drive to a mountpoint and have a look at the directory structure (if any). Copy some file to this mountpoint and look again. Now mount the second drive to the same mountpoint, the file you just copied should vanish. Unmounting the second drive will 'magically' cause the file to reappear.

You want to look into LVM instead;
http://www.tldp.org/HOWTO/LVM-HOWTO/

i had the opposite effect once.

the first drive mounted at the same spot managed to get wiped.