Re: Live Upgrade for Linux
Date: Wed, 26 Mar 2003 15:35:47 -0600 (CST) From: <email@example.com> To: Kelly Sauke <firstname.lastname@example.org>
On Tue, 25 Mar 2003, Kelly Sauke wrote:
> Maybe I need a little clarification of what Live Upgrade does. I've
> gotten a lot of response of what I would call installer utilities but
> not a Live Upgrade (if I'm wrong please point it out to me). What Live
> Upgrade does under solaris is it creates a complete alternate boot
> environment with a root /usr /var and any other filesystem you want.
> Then you can apply patches etc to this other boot environment and boot
> off of that. If there is something in the patch that doesn't work or
> screws up the machine, then you just reboot off the original boot
> environment and you're back to where you were before upgrading and still
> have access to the patched boot environment to fix it. Its great for
AFAIK, there is not a package that automates this the way that 'live
upgrade' does. However, you can do this manualy with rpm and the '--root'
option. Of course you still have to have the extra partitions to create
your alternat environment in. Once you have copied the files over to the
new partitions and modified the /etc/fstab in the new root. You need to
add an entry to grub/lilo with root=/dev/hdxx pointed at your new root
partition so you can boot to it. Then you have the task of keeping the
configuration information upto date in the alternate boot environment. I
suppose that you could use tripwire or aide to help with this.
This would be an intresting project to work on.