diff --git a/ansible/docker/Dockerfile b/ansible/docker/Dockerfile
index 8056b9f..ca6dbfb 100644
--- a/ansible/docker/Dockerfile
+++ b/ansible/docker/Dockerfile
@@ -25,6 +25,7 @@
   ansible==$ansible_version \
   jmespath \
   netaddr \
+  jsonpointer \
 && apk del build-dependencies && rm -rf /var/cache/apk/* && rm -rf /root/.cache
 
 ENV ANSIBLE_HOST_KEY_CHECKING false
diff --git a/ansible/library/json_add.py b/ansible/library/json_add.py
deleted file mode 100644
index 6aad2d7..0000000
--- a/ansible/library/json_add.py
+++ /dev/null
@@ -1,90 +0,0 @@
-#!/usr/bin/python
-
-from ansible.module_utils.basic import AnsibleModule
-import json
-import os
-
-DOCUMENTATION="""
----
-module: json_add
-descritption:
-  - This module will search top level objects in json and adds specified
-    value into list for specified key.
-  - If file does not exists module will create it automatically.
-
-options:
-  path:
-    required: true
-    aliases=[name, destfile, dest]
-    description:
-      - The json file to modify.
-  key:
-    required: true
-    description:
-      - Top level object.
-  value:
-    required: true
-    description:
-      - Value to add to specified key.
-"""
-
-def load_json(path):
-    if os.path.exists(path):
-        with open(path, 'r') as f:
-          return json.load(f)
-    else:
-        return {}
-
-def value_is_set(path, key, value, json_obj):
-    return value in json_obj.get(key, [])
-
-def insert_to_json(path, key, value, check_mode=False):
-    json_obj = load_json(path)
-    if not value_is_set(path, key, value, json_obj):
-        if not check_mode:
-            json_obj.setdefault(key, []).append(value)
-            store_json(path, json_obj)
-        return True, 'Value %s added to %s.' % (value, key)
-    else:
-        return False, ''
-
-def store_json(path, json_obj):
-    with open(path, 'w') as f:
-        json.dump(json_obj, f, indent=4)
-
-def check_file_attrs(module, changed, message, diff):
-    file_args = module.load_file_common_arguments(module.params)
-    if module.set_fs_attributes_if_different(file_args, False, diff=diff):
-
-        if changed:
-            message += ' '
-        changed = True
-        message += 'File attributes changed.'
-
-    return changed, message
-
-def run_module():
-    module = AnsibleModule(
-        argument_spec=dict(
-        path=dict(type='path', required=True, aliases=['name', 'destfile', 'dest']),
-        key=dict(type='str', required=True),
-        value=dict(type='str', required=True),
-        ),
-        add_file_common_args=True,
-        supports_check_mode=True
-    )
-    params = module.params
-    path = params['path']
-    key = params['key']
-    value = params['value']
-    try:
-        changed, msg = insert_to_json(path, key, value, module.check_mode)
-        fs_diff = {}
-        changed, msg = check_file_attrs(module, changed, msg, fs_diff)
-        module.exit_json(changed=changed, msg=msg, file_attr_diff=fs_diff)
-    except IOError as e:
-        module.fail_json(msg=e.msg)
-
-if __name__ == '__main__':
-    run_module()
-
diff --git a/ansible/library/json_mod.py b/ansible/library/json_mod.py
new file mode 100644
index 0000000..1a95c75
--- /dev/null
+++ b/ansible/library/json_mod.py
@@ -0,0 +1,328 @@
+#!/usr/bin/python
+
+from ansible.module_utils.basic import AnsibleModule
+
+import os
+import copy
+import json
+
+try:
+    import jsonpointer
+except ImportError:
+    jsonpointer = None
+
+DOCUMENTATION = """
+---
+module: json_mod
+short_description: Modifies json data inside a file
+description:
+  - This module modifies a file containing a json.
+  - It is leveraging jsonpointer module implementing RFC6901:
+    https://pypi.org/project/jsonpointer/
+    https://tools.ietf.org/html/rfc6901
+  - If the file does not exist the module will create it automatically.
+
+options:
+  path:
+    description:
+      - The json file to modify.
+    required: true
+    aliases:
+      - name
+      - destfile
+      - dest
+  key:
+    description:
+      - Pointer to the key inside the json object.
+      - You can leave out the leading slash '/'. It will be prefixed by the
+        module for convenience ('key' equals '/key').
+      - Empty key '' designates the whole JSON document (RFC6901)
+      - Key '/' is valid too and it translates to '' ("": "some value").
+      - The last object in the pointer can be missing but the intermediary
+        objects must exist.
+    required: true
+  value:
+    description:
+      - Value to be added/changed for the key specified by pointer.
+      - In the case of 'state = absent' the module will delete those elements
+        described in the value. If the whole key/value should be deleted then
+        value must be set to the empty string '' !
+    required: true
+  state:
+    description:
+      - It states either that the combination of key and value should be
+        present or absent.
+      - If 'present' then the exact results depends on 'action' argument.
+      - If 'absent' and key does not exists - no change, if does exist but
+        'value' is unapplicable (old value is dict, but new is not), then the
+        module will raise error. Special 'value' for state 'absent' is an empty
+        string '' (read above). If 'value' is applicable (both key and value is
+        dict or list) then it will remove only those explicitly named elements.
+        Please beware that if you want to remove key/value pairs from dict then
+        you must provide as 'value' a valid dict - that means key/value pair(s)
+        in curls {}. Here you can use just some dummy value like "". The values
+        can differ, the key/value pair will be deleted if key matches.
+        For example to delete key "xyz" from json object, you must provide
+        'value' similar to this: { "key": ""}
+    required: false
+    default: present
+    choices:
+      - present
+      - absent
+  action:
+    description:
+      - It modifies a presence of the key/value pair when state is 'present'
+        otherwise is ignored.
+      - 'add' is default and means that combination of key/value will be added
+        if not already there. If there is already an old value then it is
+        expected that the old value and the new value are of the same type.
+        Otherwise the module will fail. By the same type we mean that both of
+        them are either scalars (strings, numbers), lists or dicts.
+      - In the case of scalar values everything is simple - if there is already
+        a value, nothing happens.
+      - In the case of lists the module ensures that all components of the new
+        value list are present in the result - it will extend an old value list
+        with the elements of the new value list.
+      - In the case of dicts the missing key/value pairs are added but those
+        already present are preserved - it will NOT overwrite old values.
+      - 'Update' is identical to 'add', but it WILL overwrite old values. For
+        list values this has no meaning, so it behaves like add - it simply
+        merges two lists (extends the old with new).
+      - 'replace' will (re)create key/value combination from scratch - it means
+        that the old value is completely discarded if there is any.
+    required: false
+    default: add
+    choices:
+      - add
+      - update
+      - replace
+"""
+
+
+def load_json(path):
+    if os.path.exists(path):
+        with open(path, 'r') as f:
+            return json.load(f)
+    else:
+        return {}
+
+
+def store_json(path, json_data):
+    with open(path, 'w') as f:
+        json.dump(json_data, f, indent=4)
+        f.write("\n")
+
+
+def modify_json(json_data, pointer, json_value, state='present', action='add'):
+    is_root = False  # special treatment - we cannot modify reference in place
+    key_exists = False
+
+    try:
+        value = json.loads(json_value)
+    except Exception:
+        value = None
+
+    if state == 'present':
+        if action not in ['add', 'update', 'replace']:
+            raise ValueError
+    elif state == 'absent':
+        pass
+    else:
+        raise ValueError
+
+    # we store the original json document to compare it later
+    original_json_data = copy.deepcopy(json_data)
+
+    try:
+        target = jsonpointer.resolve_pointer(json_data, pointer)
+        if pointer == '':
+            is_root = True
+        key_exists = True
+    except jsonpointer.JsonPointerException:
+        key_exists = False
+
+    if key_exists:
+        if state == "present":
+            if action == "add":
+                if isinstance(target, dict) and isinstance(value, dict):
+                    # we keep old values and only append new ones
+                    value.update(target)
+                    result = jsonpointer.set_pointer(json_data,
+                                                     pointer,
+                                                     value,
+                                                     inplace=(not is_root))
+                    if is_root:
+                        json_data = result
+                elif isinstance(target, list) and isinstance(value, list):
+                    # we just append new items to the list
+                    for item in value:
+                        if item not in target:
+                            target.append(item)
+                elif ((not isinstance(target, dict)) and
+                      (not isinstance(target, list))):
+                    # 'add' does not overwrite
+                    pass
+                else:
+                    raise ValueError
+            elif action == "update":
+                if isinstance(target, dict) and isinstance(value, dict):
+                    # we append new values and overwrite the old ones
+                    target.update(value)
+                elif isinstance(target, list) and isinstance(value, list):
+                    # we just append new items to the list - same as with 'add'
+                    for item in value:
+                        if item not in target:
+                            target.append(item)
+                elif ((not isinstance(target, dict)) and
+                      (not isinstance(target, list))):
+                    # 'update' DOES overwrite
+                    if value is not None:
+                        result = jsonpointer.set_pointer(json_data,
+                                                         pointer,
+                                                         value)
+                    elif target != json_value:
+                        result = jsonpointer.set_pointer(json_data,
+                                                         pointer,
+                                                         json_value)
+                    else:
+                        raise ValueError
+                else:
+                    raise ValueError
+            elif action == "replace":
+                # simple case when we don't care what was there before (almost)
+                if value is not None:
+                    result = jsonpointer.set_pointer(json_data,
+                                                     pointer,
+                                                     value,
+                                                     inplace=(not is_root))
+                else:
+                    result = jsonpointer.set_pointer(json_data,
+                                                     pointer,
+                                                     json_value,
+                                                     inplace=(not is_root))
+                if is_root:
+                    json_data = result
+            else:
+                raise ValueError
+        elif state == "absent":
+            # we will delete the elements in the object or object itself
+            if is_root:
+                if json_value == '':
+                    # we just return empty json
+                    json_data = {}
+                elif isinstance(target, dict) and isinstance(value, dict):
+                    for key in value:
+                        target.pop(key, None)
+                else:
+                    raise ValueError
+            else:
+                # we must take a step back in the pointer, so we can edit it
+                ppointer = pointer.split('/')
+                to_delete = ppointer.pop()
+                ppointer = '/'.join(ppointer)
+                ptarget = jsonpointer.resolve_pointer(json_data, ppointer)
+                if (((not isinstance(target, dict)) and
+                        (not isinstance(target, list)) and
+                        json_value == '') or
+                        (isinstance(target, dict) or
+                         isinstance(target, list)) and
+                        json_value == ''):
+                    # we simply delete the key with it's value (whatever it is)
+                    ptarget.pop(to_delete, None)
+                    target = ptarget  # piece of self-defense
+                elif isinstance(target, dict) and isinstance(value, dict):
+                    for key in value:
+                        target.pop(key, None)
+                elif isinstance(target, list) and isinstance(value, list):
+                    for item in value:
+                        try:
+                            target.remove(item)
+                        except ValueError:
+                            pass
+                else:
+                    raise ValueError
+        else:
+            raise ValueError
+    else:
+        # the simplest case - nothing was there before and pointer is not root
+        # because in that case we would have key_exists = true
+        if state == 'present':
+            if value is not None:
+                result = jsonpointer.set_pointer(json_data,
+                                                 pointer,
+                                                 value)
+            else:
+                result = jsonpointer.set_pointer(json_data,
+                                                 pointer,
+                                                 json_value)
+
+    if json_data != original_json_data:
+        changed = True
+    else:
+        changed = False
+
+    if changed:
+        msg = "JSON object '%s' was updated" % pointer
+    else:
+        msg = "No change to JSON object '%s'" % pointer
+
+    return json_data, changed, msg
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            path=dict(type='path', required=True,
+                      aliases=['name', 'destfile', 'dest']),
+            key=dict(type='str', required=True),
+            value=dict(type='str', required=True),
+            state=dict(default='present', choices=['present', 'absent']),
+            action=dict(required=False, default='add',
+                        choices=['add',
+                                 'update',
+                                 'replace']),
+        ),
+        supports_check_mode=True
+    )
+
+    if jsonpointer is None:
+        module.fail_json(msg='jsonpointer module is not available')
+
+    path = module.params['path']
+    pointer = module.params['key']
+    value = module.params['value']
+    state = module.params['state']
+    action = module.params['action']
+
+    if pointer == '' or pointer == '/':
+        pass
+    elif not pointer.startswith("/"):
+        pointer = "/" + pointer
+
+    try:
+        json_data = load_json(path)
+    except Exception as err:
+        module.fail_json(msg=str(err))
+
+    try:
+        json_data, changed, msg = modify_json(json_data,
+                                              pointer,
+                                              value,
+                                              state,
+                                              action)
+    except jsonpointer.JsonPointerException as err:
+        module.fail_json(msg=str(err))
+    except ValueError as err:
+        module.fail_json(msg="Wrong usage of state, action and/or key/value")
+
+    try:
+        if not module.check_mode and changed:
+            store_json(path, json_data)
+    except IOError as err:
+        module.fail_json(msg=str(err))
+
+    module.exit_json(changed=changed, msg=msg)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/ansible/roles/docker/defaults/main.yml b/ansible/roles/docker/defaults/main.yml
new file mode 100644
index 0000000..1922f64
--- /dev/null
+++ b/ansible/roles/docker/defaults/main.yml
@@ -0,0 +1,4 @@
+---
+docker:
+  log_max_size: 100m
+  log_max_file: 3
diff --git a/ansible/roles/docker/tasks/main.yml b/ansible/roles/docker/tasks/main.yml
index 09e790a..16b7002 100644
--- a/ansible/roles/docker/tasks/main.yml
+++ b/ansible/roles/docker/tasks/main.yml
@@ -16,11 +16,21 @@
     path: /etc/docker
     state: directory
 
+- name: Setup docker container logging settings
+  json_mod:
+    path: /etc/docker/daemon.json
+    key: '' # the whole JSON document per https://tools.ietf.org/html/rfc6901
+    # "value" must be wrapped in single quote "'" with extra space in front of "{" (ansible workaround)
+    # reference: https://stackoverflow.com/questions/31969872
+    value: ' { "log-driver": "json-file", "log-opts": { "max-size": "{{ docker.log_max_size }}", "max-file": "{{ docker.log_max_file }}" } }'
+
 - name: Setup docker dns settings
-  json_add:
+  json_mod:
     path: /etc/docker/daemon.json
     key: dns
-    value: "{{ hostvars[groups.infrastructure[0]].cluster_ip }}"
+    # "value" must be wrapped in single quote "'" with extra space in front of "[" (ansible workaround)
+    # reference: https://stackoverflow.com/questions/31969872
+    value: ' [ "{{ hostvars[groups.infrastructure[0]].cluster_ip }}" ]'
   notify:
     - Restart Docker