[linux-lvm] Re: Extending the Root Volume with LVM

[Duane Clark <dclark akamail com>]

Sean McGlynn wrote:
> I am working with RHEL 4 Update 4.  When initially installing the OS I 
> allowed the installation to automatically partition the disk, and it 
> used LVM to create a logical volume to mount the root file system.  The 
> only other logical volume it created was for the swap file.
>  
> Now, as an experiment, I am attempting to extend the volume group and 
> logical volume on which root is mounted.  Everything appeared to 
> be going smoothly (extending the VG, extending the LV, doing a vgchange, 
> and then a lvm lvchange), but I am now at the point where I want to run 
> e2fsck to check the file system and resize2fs to resize the files system 
> to realize the added space, and I can't do either because the volume is 
> mounted, and cannot be unmounted.
>  
> I've read a few suggestions such as using the installation media to go 
> in in rescue mode, but nothing seems to do the trick. 

Why, what problems did you run into? When rescue mode asked you whether 
you wanted it to find and mount the root partitions, did you select 
"skip"? Here are step by step instructions on how I reduced the LVM (on 
FC4), including e2fsck and resize2fs.

https://www.redhat.com/archives/linux-lvm/2006-August/msg00081.html

> I also read 
> something that said that you cannot extend the root volume, and that you 
> shouldn't have to.  This appears to be more accurate than anything else 
> I've read.

Definitely not true.