This script provides an easy way to count all the nodes in all the orgs on a Chef Server

CountChefNodes.sh

# Make temp config.rb so we can ignore any ssl errors
echo "ssl_verify_mode          :verify_none" > temp_config.rb

# Pull a list of all the orgs on the server
# then loop through each one and make an api call to get the node count
chef-server-ctl org-list -a | while read -r org ; do
  echo "Attempting to connect to the $org organization."
  /opt/opscode/embedded/bin/knife exec -E "puts api.get('/nodes').size" -s https://127.0.0.1/organizations/$org -u pivotal -k /etc/opscode/pivotal.pem --config temp_config.rb
done

# Remove temp file
rm temp_config.rb