Images are stored in a custom Emulab format called imagezip. The extension is '.ndz'. This represents the raw data that will be loaded on the testbed node disks. It does not contain any of the necessary metadata about partitions, what sort of OS the image contains, etc. We have a XML file that contains this called the image descriptor file.
Standard Testbed images are located at http://www.deterlab.net/~jjh/Deter%20OS%20Images/. The standard location for testbed-wide images is on boss in /usr/testbed/images.
There is a simple script called "fetch_images" located in the install directory of the testbed source to automate downloading these images.
[jjh@boss ~/testbed/install]$ ./fetch_images
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 2045 100 2045 0 0 162k 0 --:--:-- --:--:-- --:--:-- 665k
Fetching CentOS5.ndz
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 604M 100 604M 0 0 65.2M 0 0:00:09 0:00:09 --:--:-- 74.2M
Fetching FBSD8-STD.ndz
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 443M 100 443M 0 0 74.2M 0 0:00:05 0:00:05 --:--:-- 75.2M
Fetching FBSD62-STD.ndz
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 295M 100 295M 0 0 67.5M 0 0:00:04 0:00:04 --:--:-- 67.6M
Fetching Ubuntu1004-STD.ndz
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 849M 100 849M 0 0 72.9M 0 0:00:11 0:00:11 --:--:-- 73.5M
[jjh@boss ~/testbed/install]$ cd /usr/testbed/images/
[jjh@boss /usr/testbed/images]$ ls
CentOS5.ndz FBSD62-STD.ndz FBSD8-STD.ndz Ubuntu1004-STD.ndz
[jjh@boss /usr/testbed/images]$
There is a perl script to load the appropriate image descriptors in ~<builduser>/obj/install:
[jjh@boss ~/obj/install]$ perl load-descriptors ~/testbed/install/descriptors.sql