Steve.org.uk

This example shows how to setup SSH authorized keys for a given user upon a number of systems.

First of all we'll create the content on the webserver:

mkdir -p /var/www/slaughter/
mkdir -p /var/www/slaughter/policies
mkdir -p /var/www/slaughter/files

Now we'll save the master authorized_keys file on the master, and locate it at /var/www/slaughter/files/global-keys.

The next thing to do is to write the policy. We'll seperate this out and save the following as /var/www/slaughter/policies/default.policy:

#
# This is the policy downloaded and executed by all client nodes.
#
# Useful to keep this as a file which merely includes other files.
#
#
#
# Setup authorized-keys for "skx".
#
FetchPolicy skx-keys.policy ;

Now we'll write /var/www/slaughter/policies/skx-keys.policy:

#
#  Fetch the master authorized_keys file for the user skx and install
# it appropriately.
#
#
#  Ensure the user exists.
#
if ( UserExists( User => "skx" ) )
{
    # copy
    FetchFile(
            Source => "/global-keys",
              Dest => "/home/skx/.ssh/authorized_keys2",
             Owner => "skx",
             Group => "skx",
              Mode => "0600" );
}

With these files in place you should now be able to execute the slaughter client from any host which can reach your webserver:

slaughter --keep --verbose --server example.com

Here we've added "--keep" which will prevent the compiled script from being deleted, such that you can examine it. We've pointed it at the address of your server via the --server flag and finally ensured the output is more noisy than normal with --verbose.

Below is some sample code to alert to "urgent@example.org" if any partition upon the disk is too full - which means that it is more than 80% in use.

#
#  Ensure no mount-point is "too full".
#
foreach my $point ( Mounts() )
{
   if ( PercentageUsed( path => $point ) > 80 )
   {
      Alert( To      => 'urgent@example.org',
             From    => "root",
             Subject => "$server is running out of space on $point",
             Message => "This is a friendly warning." );
   }
}

Save the previous code in /var/www/slaughter/policies/disk-check.policy, then add the following to policies/default.policy:

# check on disk space
FetchPolicy disk-check.policy;