diff --git a/README.md b/README.md
index a01aab7..d120c27 100644
--- a/README.md
+++ b/README.md
@@ -12,3 +12,35 @@
 Usage:
 ------
 
+    This tool can be used to create a new class 'environment' generated from custom inventory.
+
+Requirements
+============
+
+- Installed and configured 'reclass' package
+- Prepared 'cluster', 'system' and 'service' classes
+- [Optional] Nodes generated with salt-call state.sls reclass.storage
+
+Create 'environment' class
+==========================
+
+    # 1. Create a context file from the current reclass inventory:
+
+    reclass-create-inventory-context -d mcp11-ovs-dpdk.local > /tmp/context-mcp11-ovs-dpdk.local.yaml
+
+    # 2. Remove existing hardware-related objects from 'cluster', 'system' and 'service' classes:
+
+    reclass-remove-key -r parameters.linux.network.interface /srv/salt/reclass/classes/cluster/physical_mcp11_ovs_dpdk
+    reclass-remove-key -r parameters.linux.network.interface /srv/salt/reclass/classes/system/
+    reclass-remove-key -r parameters.linux.network.interface /usr/share/salt-formulas/reclass/
+
+    # 3. Render the 'environment' class using example template based on cookiecutter:
+
+    git clone https://github.com/dis-xcom/reclass_tools ~/reclass_tools
+    reclass-render-dir -t ~/reclass_tools/examples/environment -o /tmp/environment -c /tmp/context-mcp11-ovs-dpdk.local.yaml  # You can add multiple YAMLs here
+
+    # 4. Symlink 'environment' to the /srv/reclass/salt/classes
+
+    ln -s /tmp/environment /srv/reclass/salt/classes
+
+    # 5. Add new class '- environment.mcp11-ovs-dpdk.local' to the classes/cluster/<cluster_model>/infra/config.yml
diff --git a/examples/environment/context-mcp11-ovs-dpdk.local.yaml b/examples/environment/context-mcp11-ovs-dpdk.local.yaml
new file mode 100644
index 0000000..ed3bf3a
--- /dev/null
+++ b/examples/environment/context-mcp11-ovs-dpdk.local.yaml
@@ -0,0 +1,182 @@
+cookiecutter:
+  cluster_name: mcp11-ovs-dpdk.local
+  nodes:
+    cmp001.mcp11-ovs-dpdk.local:
+      name: cmp001
+      parameters: {}
+      reclass_storage_name: openstack_compute_node01
+      roles: []
+    cmp002.mcp11-ovs-dpdk.local:
+      name: cmp002
+      parameters: {}
+      reclass_storage_name: openstack_compute_node02
+      roles: []
+    ctl01.mcp11-ovs-dpdk.local:
+      name: ctl01
+      parameters: {}
+      reclass_storage_name: openstack_control_node01
+      roles:
+      - vcp
+    ctl02.mcp11-ovs-dpdk.local:
+      name: ctl02
+      parameters: {}
+      reclass_storage_name: openstack_control_node02
+      roles:
+      - vcp
+    ctl03.mcp11-ovs-dpdk.local:
+      name: ctl03
+      parameters: {}
+      reclass_storage_name: openstack_control_node03
+      roles:
+      - vcp
+    dbs01.mcp11-ovs-dpdk.local:
+      name: dbs01
+      parameters: {}
+      reclass_storage_name: openstack_database_node01
+      roles:
+      - vcp
+    dbs02.mcp11-ovs-dpdk.local:
+      name: dbs02
+      parameters: {}
+      reclass_storage_name: openstack_database_node02
+      roles:
+      - vcp
+    dbs03.mcp11-ovs-dpdk.local:
+      name: dbs03
+      parameters: {}
+      reclass_storage_name: openstack_database_node03
+      roles:
+      - vcp
+    gtw01.mcp11-ovs-dpdk.local:
+      name: gtw01
+      parameters: {}
+      reclass_storage_name: openstack_gateway_node01
+      roles: []
+    gtw02.mcp11-ovs-dpdk.local:
+      name: gtw02
+      parameters: {}
+      reclass_storage_name: openstack_gateway_node02
+      roles: []
+    gtw03.mcp11-ovs-dpdk.local:
+      name: gtw03
+      parameters: {}
+      reclass_storage_name: openstack_gateway_node03
+      roles: []
+    kvm01.mcp11-ovs-dpdk.local:
+      name: kvm01
+      parameters: {}
+      reclass_storage_name: infra_kvm_node01
+      roles: []
+    kvm02.mcp11-ovs-dpdk.local:
+      name: kvm02
+      parameters: {}
+      reclass_storage_name: infra_kvm_node02
+      roles: []
+    kvm03.mcp11-ovs-dpdk.local:
+      name: kvm03
+      parameters: {}
+      reclass_storage_name: infra_kvm_node03
+      roles: []
+    log01.mcp11-ovs-dpdk.local:
+      name: log01
+      parameters: {}
+      reclass_storage_name: stacklight_log_node01
+      roles:
+      - vcp
+    log02.mcp11-ovs-dpdk.local:
+      name: log02
+      parameters: {}
+      reclass_storage_name: stacklight_log_node02
+      roles:
+      - vcp
+    log03.mcp11-ovs-dpdk.local:
+      name: log03
+      parameters: {}
+      reclass_storage_name: stacklight_log_node03
+      roles:
+      - vcp
+    mdb01.mcp11-ovs-dpdk.local:
+      name: mdb01
+      parameters: {}
+      reclass_storage_name: openstack_telemetry_node01
+      roles:
+      - vcp
+    mdb02.mcp11-ovs-dpdk.local:
+      name: mdb02
+      parameters: {}
+      reclass_storage_name: openstack_telemetry_node02
+      roles:
+      - vcp
+    mdb03.mcp11-ovs-dpdk.local:
+      name: mdb03
+      parameters: {}
+      reclass_storage_name: openstack_telemetry_node03
+      roles:
+      - vcp
+    mon01.mcp11-ovs-dpdk.local:
+      name: mon01
+      parameters: {}
+      reclass_storage_name: stacklight_monitor_node01
+      roles:
+      - vcp
+    mon02.mcp11-ovs-dpdk.local:
+      name: mon02
+      parameters: {}
+      reclass_storage_name: stacklight_monitor_node02
+      roles:
+      - vcp
+    mon03.mcp11-ovs-dpdk.local:
+      name: mon03
+      parameters: {}
+      reclass_storage_name: stacklight_monitor_node03
+      roles:
+      - vcp
+    msg01.mcp11-ovs-dpdk.local:
+      name: msg01
+      parameters: {}
+      reclass_storage_name: openstack_message_queue_node01
+      roles:
+      - vcp
+    msg02.mcp11-ovs-dpdk.local:
+      name: msg02
+      parameters: {}
+      reclass_storage_name: openstack_message_queue_node02
+      roles:
+      - vcp
+    msg03.mcp11-ovs-dpdk.local:
+      name: msg03
+      parameters: {}
+      reclass_storage_name: openstack_message_queue_node03
+      roles:
+      - vcp
+    mtr01.mcp11-ovs-dpdk.local:
+      name: mtr01
+      parameters: {}
+      reclass_storage_name: stacklight_telemetry_node01
+      roles:
+      - vcp
+    mtr02.mcp11-ovs-dpdk.local:
+      name: mtr02
+      parameters: {}
+      reclass_storage_name: stacklight_telemetry_node02
+      roles:
+      - vcp
+    mtr03.mcp11-ovs-dpdk.local:
+      name: mtr03
+      parameters: {}
+      reclass_storage_name: stacklight_telemetry_node03
+      roles:
+      - vcp
+    prx01.mcp11-ovs-dpdk.local:
+      name: prx01
+      parameters: {}
+      reclass_storage_name: openstack_proxy_node01
+      roles:
+      - vcp
+    prx02.mcp11-ovs-dpdk.local:
+      name: prx02
+      parameters: {}
+      reclass_storage_name: openstack_proxy_node02
+      roles:
+      - vcp
+
diff --git "a/examples/environment/\173\173 cookiecutter.cluster_name \175\175/init.yml" "b/examples/environment/\173\173 cookiecutter.cluster_name \175\175/init.yml"
new file mode 100644
index 0000000..633ed40
--- /dev/null
+++ "b/examples/environment/\173\173 cookiecutter.cluster_name \175\175/init.yml"
@@ -0,0 +1,16 @@
+parameters:
+  reclass:
+    storage:
+      node:
+{%- for inventory_node_name, node in cookiecutter.nodes.items() %}
+        {{ node['reclass_storage_name'] }}:
+          params:
+{%- if 'vcp' in node['roles'] %}
+            linux_network_interfaces:
+              ens3: ${_param:linux_single_interface}
+{%- else %}
+            linux_network_interfaces: None  # Create interfaces configuration from your inventory
+{%- endif %}
+          classes:
+          - environment.{{ cookiecutter.cluster_name }}.networking
+{%- endfor %}
diff --git "a/examples/environment/\173\173 cookiecutter.cluster_name \175\175/networking.yml" "b/examples/environment/\173\173 cookiecutter.cluster_name \175\175/networking.yml"
new file mode 100644
index 0000000..1ef4d17
--- /dev/null
+++ "b/examples/environment/\173\173 cookiecutter.cluster_name \175\175/networking.yml"
@@ -0,0 +1,4 @@
+parameters:
+  linux:
+    network:
+      interface: ${_param:linux_network_interfaces}
diff --git a/reclass_tools/cli.py b/reclass_tools/cli.py
index 1bd80b7..becff4e 100644
--- a/reclass_tools/cli.py
+++ b/reclass_tools/cli.py
@@ -128,6 +128,7 @@
     params = parser.parse_args(args)
 
     vcp_node_names = reclass_models.vcp_list(domain=params.domain)
+    #print('\n'.join(sorted(vcp_node_names)))
     print('\n'.join(sorted(('{0}.{1}'.format(name, domain) for name, domain in vcp_node_names))))
 
 
@@ -152,3 +153,26 @@
 
     print(yaml.dump(current_underlay_context, default_flow_style=False))
 
+
+def render_dir(args=None):
+    try:
+        from reclass_tools import create_inventory
+    except ImportError:
+        print("Please run this tool on the salt-master node with installed 'reclass'")
+        return
+
+    parser = argparse.ArgumentParser(formatter_class=argparse.RawTextHelpFormatter,
+                                     description="Render a coockiecutter-based template directory using several different context files")
+    parser.add_argument('--template-dir', '-t', dest='template_dir',
+                        help=('Coockiecutter-based template directory'))
+    parser.add_argument('--output-dir', '-o', dest='output_dir',
+                        help=('Path to the directory where the rendered template will be placed'))
+    parser.add_argument('--context', '-c', dest='contexts',
+                        help=('Path to the directory where the rendered template will be placed'),
+                        nargs='+')
+
+    params = parser.parse_args(args)
+
+    create_inventory.render_dir(template_dir=params.template_dir, output_dir=params.output_dir, contexts=params.contexts)
+
+
diff --git a/reclass_tools/create_inventory.py b/reclass_tools/create_inventory.py
index 26ad89e..ce0d7a6 100644
--- a/reclass_tools/create_inventory.py
+++ b/reclass_tools/create_inventory.py
@@ -40,12 +40,17 @@
     vcp_list = reclass_models.vcp_list(domain=domain, inventory=inventory)
     reclass_storage = reclass_models.reclass_storage(domain=domain, inventory=inventory)
 
-    current_underlay_context = {
-        'current_clusters': {
-        }
-    }
+    if domain is None:
+        raise Exception("Please specify a domain name from: \n{}".format('\n'.join(reclass_storage.keys())))
 
-    for domain, storage_nodes in reclass_storage.items():
+    #current_underlay_context = {
+    #    'current_clusters': {
+    #    }
+    #}
+
+    for storage_domain, storage_nodes in reclass_storage.items():
+        if storage_domain != domain:
+            continue
 
         current_cluster_nodes = {}
         for storage_node_name, storage_node in storage_nodes.items():
@@ -73,8 +78,14 @@
                     if reclass_key:
                         helpers.create_nested_key(current_cluster_nodes[inventory_node_name], path=key_path, value=reclass_key)
 
-        current_underlay_context['current_clusters'][domain] = {
-            'nodes': current_cluster_nodes
+        #current_underlay_context['current_clusters'][domain] = {
+        #    'nodes': current_cluster_nodes
+        #}
+        current_underlay_context = {
+            'cookiecutter': {
+                'cluster_name': storage_domain,
+                'nodes': current_cluster_nodes,
+            }
         }
 
     return current_underlay_context
@@ -106,7 +117,7 @@
 #                ..
 
 
-def render_environment_class():
+def render_dir(template_dir, output_dir, contexts):
     """Coockiecutter echancement to use several source JSON files
 
     :param template_dir: directory with templates to render
@@ -126,15 +137,36 @@
 #ipdb> output_dir
 #'/root/my_new_deployment/'
 
-    repo_dir = '/root/cookiecutter-templates/cluster_product/openstack'
+    print(template_dir)
+    print(output_dir)
+    print(contexts)
+    #return
+    #repo_dir = '/root/cookiecutter-templates/cluster_product/openstack'
     overwrite_if_exists = True
-    output_dir = '/root/my_new_deployment/'
-    context = {'cookiecutter': {'openstack_telemetry_node02_hostname': 'mdb02' }}
+    #output_dir = '/root/my_new_deployment/'
+    #context = {'cookiecutter': {'openstack_telemetry_node02_hostname': 'mdb02' }}
+
+    merged_context = {}
+    for fcon in contexts:
+        if fcon.endswith('.yaml'):
+            context = helpers.yaml_read(fcon)
+        elif fcon.endswith('.json'):
+            context = helpers.json_read(fcon)
+        else:
+            print("Error: Please use YAML or JSON files for contexts")
+            return # should be exit 1
+
+
+        #merged_context.update(context)
+        #merged_context = dict(chain(merged_context.items(), context.items()))
+        merged_context = helpers.merge_nested_objects(merged_context, context)
+
+    #print(yaml.dump(merged_context, default_flow_style=False))
 
     try:
         generate.generate_files(
-            repo_dir=repo_dir,
-            context=context,
+            repo_dir=template_dir,
+            context=merged_context,
             overwrite_if_exists=overwrite_if_exists,
             output_dir=output_dir
         )
@@ -146,7 +178,6 @@
 
         context_str = yaml.dump(
             undefined_err.context,
-            indent=4,
             default_flow_style=False
         )
         print('='*15 + ' Context: '+ '='*15 + '\n{}'.format(context_str) + '='*40)
diff --git a/reclass_tools/helpers.py b/reclass_tools/helpers.py
index 75e3185..322ac71 100644
--- a/reclass_tools/helpers.py
+++ b/reclass_tools/helpers.py
@@ -1,3 +1,7 @@
+import os
+import json
+import yaml
+
 
 def get_nested_key(data, path=None):
     if type(path) is not list:
@@ -42,3 +46,134 @@
             path = path[:-1]
 
 
+def yaml_read(yaml_file):
+    if os.path.isfile(yaml_file):
+        with open(yaml_file, 'r') as f:
+            return yaml.load(f)
+    else:
+        print("\'{}\' is not a file!".format(yaml_file))
+
+
+def json_read(yaml_file):
+    if os.path.isfile(yaml_file):
+        with open(yaml_file, 'r') as f:
+            return json.load(f)
+    else:
+        print("\'{}\' is not a file!".format(yaml_file))
+
+
+def merge_nested_objects(obj_1, obj_2):
+    """Merge two objects with optional key overwrites
+
+    Original : https://stackoverflow.com/a/17860173
+    - Merges dicts and lists
+    - If a dict key has the suffix '__overwrite__' and boolean value,
+      then the key is assumed as a special keyword for merging:
+      <key>__overwrite__: True   #  Overwrite the existing <key> content with <key> from obj_2
+      <key>__overwrite__: False  #  Keep the existing <key> content from obj_1
+
+
+      Case #1: Merge dicts and lists, overwrite other types with latest value
+
+        dict_a = {
+          'host': '1.1.1.1',
+          'ssh': {
+            'login': 'user'
+          }
+        }
+
+        dict_b = {
+          'host': '2.2.2.2',
+          'ssh': {
+            'password': 'pass'
+          }
+        }
+
+        print(merge_nested_objects(dict_a, dict_b))
+        {
+          'host': '2.2.2.2',
+          'ssh': {
+            'login': 'user',
+            'password': 'pass',
+          }
+        }
+
+      Case #2: Use <key>__overwrite__: True to remove previous key content
+
+        dict_a = {
+          'host': '1.1.1.1'
+          'ssh': {
+            'login': 'user'
+          }
+        }
+
+        dict_b = {
+          'ssh__overwrite__': True
+          'ssh': {
+            'password': 'pass'
+          }
+        }
+
+        print(merge_nested_objects(dict_a, dict_b))
+        {
+          'host': '1.1.1.1',
+          'ssh': {
+            'password': 'pass',
+          }
+        }
+
+      Case #3: Use <key>__overwrite__: False to skip merging key if already exists
+
+        dict_a = {
+          'host': '1.1.1.1'
+          'ssh': {
+            'login': 'user'
+          }
+        }
+
+        dict_b = {
+          'host__overwrite__': False
+          'host': '2.2.2.2'
+          'ssh': {
+            'login__overwrite__': False
+            'login': 'new_user'
+            'password': 'pass'
+          }
+        }
+
+        print(merge_nested_objects(dict_a, dict_b))
+        {
+          'host': '1.1.1.1',
+          'ssh': {
+            'login': 'user',
+            'password': 'pass'
+          }
+        }
+
+
+    """
+    # Merge two dicts
+    if isinstance(obj_1, dict) and isinstance(obj_2, dict):
+        result = {}
+        for key, value in obj_1.iteritems():
+            if key not in obj_2:
+                result[key] = value
+            else:
+                overwrite_key = key + '__overwrite__'
+                if overwrite_key in obj_2 and obj_2[overwrite_key] == True:
+                    result[key] = obj_2[key]
+                elif overwrite_key in obj_2 and obj_2[overwrite_key] == False:
+                    result[key] = value
+                else:
+                    result[key] = merge_nested_objects(value, obj_2[key])
+        for key, value in obj_2.iteritems():
+            if key not in obj_1:
+                result[key] = value
+        return result
+
+    # Add two lists
+    if isinstance(obj_1, list) and isinstance(obj_2, list):
+        return obj_1 + obj_2
+
+    # Overwrite a value with new one
+    return obj_2
diff --git a/reclass_tools/walk_models.py b/reclass_tools/walk_models.py
index d57aef5..7017722 100644
--- a/reclass_tools/walk_models.py
+++ b/reclass_tools/walk_models.py
@@ -32,12 +32,12 @@
             yield (log)
 
 
-def yaml_read(yaml_file):
-    if os.path.isfile(yaml_file):
-        with open(yaml_file, 'r') as f:
-            return yaml.load(f)
-    else:
-        print("\'{}\' is not a file!".format(yaml_file))
+#def yaml_read(yaml_file):
+#    if os.path.isfile(yaml_file):
+#        with open(yaml_file, 'r') as f:
+#            return yaml.load(f)
+#    else:
+#        print("\'{}\' is not a file!".format(yaml_file))
 
 
 class OpenFile(object):
@@ -110,7 +110,7 @@
     for path in paths:
         for log in walkfiles(path, verbose):
             if log.fname.endswith('.yml'):
-                model = yaml_read(log.fname)
+                model = helpers.yaml_read(log.fname)
                 if model is not None:
                     # Collect all params from the models
                     _param = helpers.get_nested_key(model, ['parameters', '_param'])
@@ -140,7 +140,7 @@
     for path in paths:
         for fyml in walkfiles(path, verbose=verbose):
             if fyml.fname.endswith('.yml'):
-                model = yaml_read(fyml.fname)
+                model = helpers.yaml_read(fyml.fname)
                 if model is not None:
 
                     # Clear linux.network.interfaces
diff --git a/setup.cfg b/setup.cfg
index 985cf66..bad4709 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -32,3 +32,4 @@
     reclass-inventory-list = reclass_tools.cli:inventory_list
     reclass-vcp-list = reclass_tools.cli:vcp_list
     reclass-create-inventory-context = reclass_tools.cli:create_inventory_context
+    reclass-render-dir = reclass_tools.cli:render_dir