LVM -- removing logical volumes from a file system

[Joel Rees]

On 2006/09/23, at 7:46, tokyoi at mac.com wrote:

> Dear All,
>
> I have come to the conclusion that I would be better off managing  
> the partitions on my system (fully updated FC5, KDE) myself, rather  
> than wandering through the ethereal

ethereal? That's a separate project. <grin/>

> reaches of the LV system. The GUI is a dead loss, not least because  
> it keeps telling me that elements of the system are uninitialized  
> when I am actually using them on a daily basis.

I also find it to be somewhat counter-intuitive.

> The command-line LVM programme is more appealing but I am not  
> really sure as to what will happen to my system -- as in the  
> physical bits and bobs -- if I tell lvm to remove a volume. Am I  
> right in thinking that the various commands to remove volumes  
> simply mean that logical volume management is disabled and that the  
> data remains intact, for me to administer it again via fdisk and / 
> etc/fstab?

I don't think so. At least, I don't think LVM builds partitions of  
the same kind as fdisk, nor do I think they are of the same kind as  
MSDOS/Windows "extended" logical partitions.

I think the data itself isn't usually erased or changed, but I  
wouldn't depend on being able to assemble an equivalent partition  
structure with fdisk, or with any other means I know of.

> I have more backups than Soft Mick but would rather leave them as  
> an unused comfort zone. I have looked through the man pages and the  
> like but would appreciate confirmation from those who are more  
> knowledgeable than I.

I would not expect to not use the backups.

I couldn't use LVM in FC3 or 4, but FC5 seems to work better. I don't  
remember exactly what I did to get around that uninitialized warning,  
or whether I did. What I did to figure it out was use my second drive  
(that I now have hanging off a different controller) to experiment  
with until I got a feel of what LVM does.