Testing changes in FAI

[Paul Lussier]

Hi folks,

I've inherited a legacy FAI configuration.  Currently it's running FAI
2.8.4.  We're thinking of upgrading to 2.10.x at some point, but
before that we need to completely understand everything that FAI is
currently doing for us.

Our entire configuration is currently under revision control, and one
of the things we'd like to do is test our config changes before we
commit them back to the repository.

Is there currently a way to answering the question "What would FAI
do?" for a given host *other* than actually FAI'ing that host?

I'm thinking of some kind of script which would recurse through the
config hierarchy and evaluate files and scripts to determine things
like:

 - which classes a given host is in
 - which scripts would run and what the output/results of those
   scripts would be
 - which disk config would be used
 - what files would be installed (via fcopy)
 - what packages would be installed (and what dependencies would get
   dragged in)

In theory, this script could be given a hostname of some machine and
run this test as if it were that host doing the actual FAI install.
Sort of a lint for FAI type of thing.

Obviously, since that host would not actually be installing, this
script would not be able to actually do certain things like partition
disks, fcopy files, and install packages.  But it could certain
provide a significant amount testing to any given configuration change
and inform you whether or not the change would result in the desired
outcome when you do actually go and install the host.

The FAI softupdate feature seems like it might be a good place to
start, but appears to have to actually run on the host.

Thoughts, comments, suggestions, ideas?

Thanks.
-- 
Seeya,
Paul