diff --git a/schema/op-mode-definition.rnc b/schema/op-mode-definition.rnc
new file mode 100644
index 000000000..6b5599703
--- /dev/null
+++ b/schema/op-mode-definition.rnc
@@ -0,0 +1,113 @@
+# interface_definition.rnc: VyConf reference tree XML grammar
+#
+# Copyright (C) 2014. 2017 VyOS maintainers and contributors <maintainers@vyos.net>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
+# USA
+
+# The language of this file is compact form RELAX-NG
+# http://relaxng.org/compact-tutorial-20030326.htm
+# (unless converted to XML, then just RELAX-NG :)
+
+# Interface definition starts with interfaceDefinition tag that may contain node tags
+start = element interfaceDefinition
+{
+ node*
+}
+
+# node tag may contain node, leafNode, or tagNode tags
+# Those are intermediate configuration nodes that may only contain
+# other nodes and must not have values
+node = element node
+{
+ (ownerAttr? & nodeNameAttr),
+ (properties? & children? & command?)
+}
+
+# Tag nodes are containers for nodes without predefined names, like network interfaces
+# or user names (e.g. "interfaces ethernet eth0" or "user jrandomhacker")
+# Tag nodes may contain node and leafNode elements, and also nameConstraint tags
+# They must not contain other tag nodes
+tagNode = element tagNode
+{
+ (ownerAttr? & nodeNameAttr),
+ (properties? & children & command?)
+}
+
+# Leaf nodes are terminal configuration nodes that can't have children,
+# but can have values.
+
+leafNode = element leafNode
+{
+ nodeNameAttr,
+ command,
+ properties
+}
+
+# Normal and tag nodes may have children
+children = element children
+{
+ (node | tagNode | leafNode)+
+}
+
+# Nodes may have properties
+# For simplicity, any property is allowed in any node,
+# but whether they are used or not is implementation-defined
+
+
+properties = element properties
+{
+ help? &
+ completionHelp*
+}
+
+# All nodes must have "name" attribute
+nodeNameAttr = attribute name
+{
+ text
+}
+
+# Ordinary nodes and tag nodes can have "owner" attribute.
+# Owner is the component that is notified when node changes.
+ownerAttr = attribute owner
+{
+ text
+}
+
+
+
+# help tags contains brief description of the purpose of the node
+help = element help
+{
+ text
+}
+
+command = element command
+{
+ text
+}
+
+# completionHelp tags contain information about allowed values of a node that is used for generating
+# tab completion in the CLI frontend and drop-down lists in GUI frontends
+# It is only meaninful for leaf nodes
+# Allowed values can be given as a fixed list of values (e.g. <list>foo bar baz</list>),
+# as a configuration path (e.g. <path>interfaces ethernet</path>),
+# or as a path to a script file that generates the list (e.g. <script>/usr/lib/foo/list-things</script>
+completionHelp = element completionHelp
+{
+ (element list { text })* &
+ (element path { text })* &
+ (element script { text })*
+}
\ No newline at end of file
diff --git a/schema/op-mode-definition.rng b/schema/op-mode-definition.rng
deleted file mode 100644
index 298ede642..000000000
--- a/schema/op-mode-definition.rng
+++ /dev/null
@@ -1,182 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<grammar xmlns="http://relaxng.org/ns/structure/1.0">
- <!--
- interface_definition.rnc: VyConf reference tree XML grammar
-
- Copyright (C) 2014. 2017 VyOS maintainers and contributors <maintainers@vyos.net>
-
- This library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- This library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with this library; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
- USA
- -->
- <!--
- The language of this file is compact form RELAX-NG
- http://relaxng.org/compact-tutorial-20030326.htm
- (unless converted to XML, then just RELAX-NG :)
- -->
- <!-- Interface definition starts with interfaceDefinition tag that may contain node tags -->
- <start>
- <element name="interfaceDefinition">
- <zeroOrMore>
- <ref name="node"/>
- </zeroOrMore>
- </element>
- </start>
- <!--
- node tag may contain node, leafNode, or tagNode tags
- Those are intermediate operational nodes that may only contain
- other nodes and must not have values
- -->
- <define name="node">
- <element name="node">
- <interleave>
- <optional>
- <ref name="ownerAttr"/>
- </optional>
- <ref name="nodeNameAttr"/>
- </interleave>
- <interleave>
- <optional>
- <ref name="properties"/>
- </optional>
- <optional>
- <ref name="command"/>
- </optional>
- <optional>
- <ref name="children"/>
- </optional>
- </interleave>
- </element>
- </define>
- <!--
- Tag nodes are containers for nodes without predefined names, like network interfaces
- or user names (e.g. "interfaces ethernet eth0" or "user jrandomhacker")
- Tag nodes may contain node and leafNode elements, and also nameConstraint tags
- They must not contain other tag nodes
- -->
- <define name="tagNode">
- <element name="tagNode">
- <interleave>
- <optional>
- <ref name="ownerAttr"/>
- </optional>
- <ref name="nodeNameAttr"/>
- </interleave>
- <interleave>
- <optional>
- <ref name="properties"/>
- </optional>
- <optional>
- <ref name="command"/>
- </optional>
- <ref name="children"/>
- </interleave>
- </element>
- </define>
- <!--
- Leaf nodes are terminal operational nodes that can't have children,
- but can have values.
- Leaf node may contain one or more valueConstraint tags
- -->
- <define name="leafNode">
- <element name="leafNode">
- <ref name="nodeNameAttr"/>
- <ref name="properties"/>
- <ref name="command"/>
- </element>
- </define>
- <!-- Normal and tag nodes may have children -->
- <define name="children">
- <element name="children">
- <oneOrMore>
- <choice>
- <ref name="node"/>
- <ref name="tagNode"/>
- <ref name="leafNode"/>
- </choice>
- </oneOrMore>
- </element>
- </define>
- <!--
- Nodes may have properties
- For simplicity, any property is allowed in any node,
- but whether they are used or not is implementation-defined
-
- -->
- <define name="properties">
- <element name="properties">
- <interleave>
- <optional>
- <ref name="help"/>
- </optional>
- <zeroOrMore>
- <ref name="completionHelp"/>
- </zeroOrMore>
- </interleave>
- </element>
- </define>
- <!-- All nodes must have "name" attribute -->
- <define name="nodeNameAttr">
- <attribute name="name"/>
- </define>
- <!--
- Ordinary nodes and tag nodes can have "owner" attribute.
- Owner is the component that is notified when node changes.
- -->
- <define name="ownerAttr">
- <attribute name="owner"/>
- </define>
-
- <!-- help tags contains brief description of the purpose of the node -->
- <define name="help">
- <element name="help">
- <text/>
- </element>
- </define>
-
- <define name="command">
- <element name="command">
- <text/>
- </element>
- </define>
-
- <!--
- completionHelp tags contain information about allowed values of a node that is used for generating
- tab completion in the CLI frontend and drop-down lists in GUI frontends
- Allowed values can be given as a fixed list of values (e.g. <list>foo bar baz</list>),
- as a configuration path (e.g. <path>interfaces ethernet</path>),
- or as a path to a script file that generates the list (e.g. <script>/usr/lib/foo/list-things</script>
- -->
- <define name="completionHelp">
- <element name="completionHelp">
- <interleave>
- <zeroOrMore>
- <element name="list">
- <text/>
- </element>
- </zeroOrMore>
- <zeroOrMore>
- <element name="path">
- <text/>
- </element>
- </zeroOrMore>
- <zeroOrMore>
- <element name="script">
- <text/>
- </element>
- </zeroOrMore>
- </interleave>
- </element>
- </define>
-</grammar>