Re: Migrating a VM

[Colin Percival <cperciva@tarsnap.com>]

On 10/03/17 07:28, Dimitris Maroulidis wrote:
> I have a an ubuntu xenial vm on AWS which I want to migrate to Google
> Cloud, and its root filesystem is backed up daily to tarsnap. How would
> I go about doing that?

Easiest solution is to launch a new VM in GCP and rsync your files across
into a subdirectory; then move things into the appropriate places.  Trying
to do a "bare metal" sync runs into two problems:

1. You need to have "a place to stand" (aka. a running system) before you
can do anything, so you can't copy onto an "empty disk" unless you play
crazy games with booting into memory disks.

2. There are usually subtle differences between how things work in different
clouds, which will have been taken care of in the base OS images for the
platform; you don't want to overwrite those.

I suggest rsync rather than tarsnap simply because there's no need to restore
from a backup if you have the original system still running; rsync will
probably be faster.  But you could extract an archive from tarsnap instead if
you prefer.

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid