how to replace kernel on Ubuntu

[David Fox]

On Fri, Oct 9, 2009 at 2:08 AM, loody <miloody at gmail.com> wrote:

> 1. what is UUID used for? It seems replace "root=/dev/sda1"
>    is there any tool or command I have to do to getting this number?

It stands for Unique User ID. It is a unique number that uniquely
identifies a specfic volume to avoid behavior that might arise
depending on inserting/removing certain USB sticks, which could cause
the stick to be mounted wrongly which causes problems. It is much more
useful on removable storage than on fixed storage, but you never know
what will happen in the future, you may decide to upgrade and install
the drives wrong, which could be disastrous :(.


> 2. from 2.6, we use initramfs instead of initrd, but why we still need
> to add "initrd" option in menu.lst.

Mostly everything is initramfs. If done correctly, all the nice things
are done at install time by scripts. Updating kernels in Ubuntu can be
made a very simple process, but be a complete headach if not done the
right way. I recommend, unlless there is a compelling reason not to,
to always install your kernel via the normal aptitude update process.
If you have the meta package linux-image installled, you always get
the most current version available, and distribution upgrades (ubuntu
to karmic for example) nearly always ge the most current version
available then, and new updates always grab new kernels if they are
available.

I do not recommend going to prior versions unless you know what you're
doing. Most of the prior versions will already be living in your grup
list so there is always an fallback in case something goes wrong. If
you're short on space you can remove ones you probably will not use
again with computer-janitor (note that the Karmic vesion does kernel
removall but the Jaunty version doesn't seem to. All the dependencies
based on a single rev of the kernel total to some large amount of
space on your filesystem.





-- 
thanks for letting me change the magnetic patterns on your hard disk.