Remove creation of SSH keys of type DSA to prevent cluster creation failure

when the OS ships a version of OpenSSH that does not support DSA keys.

Author: gmarciani

cookbooks/aws-parallelcluster-environment/files/login_nodes/keys-manager.sh

@@ -38,9 +38,6 @@ function create_keys() {
   ssh-keygen -t ecdsa -f "$FOLDER_PATH/ssh_host_ecdsa_key" -q -P ""
   ssh-keygen -t ed25519 -f "$FOLDER_PATH/ssh_host_ed25519_key" -q -P ""
   ssh-keygen -t rsa -f "$FOLDER_PATH/ssh_host_rsa_key" -q -P ""
-  if is_ubuntu; then
-    ssh-keygen -t dsa -f "$FOLDER_PATH/ssh_host_dsa_key" -q -P ""
-  fi
 }
 
 function import_keys() {
@@ -50,7 +47,6 @@ function import_keys() {
   cp "$FOLDER_PATH/ssh_host_ed25519"* /etc/ssh/
   cp "$FOLDER_PATH/ssh_host_rsa"* /etc/ssh/
   if is_ubuntu; then
-    cp "$FOLDER_PATH/ssh_host_dsa"* /etc/ssh/
     chown root:root /etc/ssh/ssh_host_*
     chmod 600 /etc/ssh/ssh_host_*_key
   else

cookbooks/aws-parallelcluster-environment/test/controls/login_nodes_keys_spec.rb

@@ -11,9 +11,6 @@
 
 key_types = %w(ecdsa ed25519 rsa)
 is_ubuntu = os_properties.ubuntu?
-if is_ubuntu
-  key_types << 'dsa'
-end
 
 control 'head_node_directory_initialized' do
   only_if { instance.head_node? && node['cluster']['scheduler'] != 'awsbatch' }