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Hi all,
I'm preparing some cloud images for the major Linux distributions and I'd like they to grow their root fs on boot (to use all the available space).

Ubuntu cloud images (http://cloud-images.ubuntu.com) use initramfs-growroot but installing it (and maintaining it across kernel upgrade) could be tricky -at least for me- on redhat derived like centos or fedora. 

So my question is: what are pros and cons of using an ext3/4 root-fs and initramfs-growroot, or LVM (with a custom script that runs on first boot)?

Thanks,
 Davide.