Description of problem:

the images provided by 
katello-installer --foreman-plugin-discovery-install-images=true

are corrupted 

Version-Release number of selected component (if applicable):

sat 6.0.6
foreman-discovery 1.3.0

How reproducible:


Steps to Reproduce:
1. install satellite with subscription manager following this:
https://access.redhat.com/products/red-hat-satellite/get-started
2. install katello with the host serving as dhcp and dns server in a closed network of hosts set prior to installation.

katello-installer --capsule-dns true --capsule-dns-forwarders "{host_ip}" --capsule-dns-interface {host_interface} --capsule-dns-zone something.com --capsule-dhcp true --capsule-dhcp-gateway {host_ip} --capsule-dhcp-interface {host_interface} --capsule-dhcp-nameservers {host_ip} --capsule-dhcp-range "192.168.105.10 192.168.105.100" --capsule-tftp true --capsule-tftp-servername {host_ip}

3. install foreman-plugin-discovery to get disovery images:

katello-installer --foreman-plugin-discovery-install-images=true

4. set /var/lib/tftpboot/pxelinux.cfg/default:

DEFAULT menu
PROMPT 0
MENU TITLE PXE Menu
TIMEOUT 50
TOTALTIMEOUT 6000
ONTIMEOUT discovery
 
LABEL local
     MENU LABEL (local)
     MENU DEFAULT
     LOCALBOOT 0
 
LABEL discovery
  MENU LABEL Foreman Discovery
  MENU DEFAULT
  KERNEL boot/foreman-discovery-image-latest.el6.iso-vmlinuz
  APPEND rootflags=loop initrd=boot/foreman-discovery-image-latest.el6.iso-img  root=live:/foreman.iso rootfstype=auto ro rd.live.image rd.live.check rd.lvm=0 rootflags=ro crashkernel=128M elevator=deadline max_loop=256 rd.luks=0 rd.md=0 rd.dm=0 nomodeset selinux=0 stateless foreman.url=https://{foreman_url} rootpw={foreman_root_pw}.
  IPAPPEND 2

5. start a host (or vm for testing) which is connected only to inner network with foreman host, start from pxe and choose foreman-discovery.

Actual results:

get an error: "invalid or corrupt kernel image".

Expected results:

host discovery is complete and host is available for provisioning on satellite. 

Additional info:

After replacing both images with images from a different working setup of satellite, discovery worked.