diff --git a/scripts/lib/install b/scripts/lib/install
index d57ecdcc6e..6b00b8a803 100755
--- a/scripts/lib/install
+++ b/scripts/lib/install
@@ -69,7 +69,7 @@ EOF
 
 # Shell option parsing.  Over time, we'll want to move some of the
 # environment variables below into this self-documenting system.
-args="$(getopt -o '' --long help,hostname:,email:,certbot,self-signed-cert,cacert:,postgresql-database-name:,postgresql-database-user:,postgresql-version:,postgresql-missing-dictionaries,no-init-db,no-overwrite-settings,no-dist-upgrade -n "$0" -- "$@")"
+args="$(getopt -o '' --long help,hostname:,email:,certbot,self-signed-cert,cacert:,postgresql-database-name:,postgresql-database-user:,postgresql-version:,postgresql-missing-dictionaries,no-init-db,puppet-classes:,no-overwrite-settings,no-dist-upgrade -n "$0" -- "$@")"
 eval "set -- $args"
 while true; do
     case "$1" in