Resize an EC2 instance with EBS root

resize EC2 instance.rb

require 'fog'

current_id    = 'i-abcdef'
new_flavor    = 'm1.large'

ec2    = Fog::Compute.new(provider: 'AWS')
source = ec2.servers.get(current_id)
dest   = ec2.servers.create(
           # specify the new instance size
           flavor_id:       new_flavor,
           # set other necessary attributes; in this case we'll copy a few from
           # the source server
           image_id:        source.image_id,
           security_groups: source.groups,
           key_name:        source.key_name
         )

# once booted, stop the dest and destroy its EBS root
dest.wait_for { ready? }
dest.stop
dest.wait_for { state == "stopped" }
v = dest.volumes.first
v.force_detach
v.destroy

# stop the source and unmount its EBS root
source.stop
source.wait_for { state == "stopped" }
volume = source.volumes.first
volume.force_detach

# attach the EBS root to the destination server and start it
volume.server = dest
dest.start

# verify all is well, then terminate the source server
#source.destroy