Re: Generate AMI from DOMU

[Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost>]

Le 22/10/2014 02:38, Louis Guillaume a écrit :
> Hello,
>
> Is there was a way to convert an existing DOMU (NetBSD or Linux)
> running on a NetBSD DOM0 into an AMI?
>
> The disks presented to the DOMUs are all Logical Volumes, so I have,
> for example:
>
>   disk = [
>            'phy:/dev/mapper/vg1-lv0,0x01,w'
>          ]
>
>   vif = [ 'bridge=bridge0' ]
>   root = "xbd0"

AFAICT, two possibilities. Sadly they both involve tweaking your image a 
bit, after all an EC2 instance is not exactly the same as a dom0 on your 
host.

=== 1 ===

The guide [1] shows you how to add the /etc/rc.d/ec2_init script to your 
image as well as adding an EXT2 partition for Grub (required for pygrub 
booting in EC2):

[1] http://wiki.netbsd.org/amazon_ec2/build_your_own_ami/

For your LV you need to dump the root volume to an image file.

=== 2 ===

ec2-import-instance can do part of the job for you, however I never used 
it (and I don't know if it works). This requires building a volume in a 
format supported by AWS (VMDK), throuh a utility like qemu-img.

I'd suggest doing 1) first, then try 2) to automate the upload part a 
bit more if required.


Beware of your network configuration when migrating your VM (like IP 
addresses and such). DHCP in /etc/ifconfig.xennet0 (and its equivalent 
for your Linux distro) is highly recommended.

> Also - what about the other way around?

Follow the export EC2 image guide at

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ExportingEC2Instances.html

and export the image in VMWare format (VMDK). Then convert the vmdk to 
raw with qemu-img:

    qemu-img convert -f vmdk -O raw src.vmdk dest.img

then use the dest.img any way you want (mounting it through vnconfig(8) 
should work, as well as dd(1) it to a fresh LV).


Good luck :)

--
Jean-Yves Migeon