draft-ietf-netmod-interfaces-cfg-02.txt   draft-ietf-netmod-interfaces-cfg-03.txt 
Network Working Group M. Bjorklund Network Working Group M. Bjorklund
Internet-Draft Tail-f Systems Internet-Draft Tail-f Systems
Intended status: Standards Track September 7, 2011 Intended status: Standards Track February 8, 2012
Expires: March 10, 2012 Expires: August 11, 2012
A YANG Data Model for Interface Configuration A YANG Data Model for Interface Configuration
draft-ietf-netmod-interfaces-cfg-02 draft-ietf-netmod-interfaces-cfg-03
Abstract Abstract
This document defines a YANG data model for the configuration of This document defines a YANG data model for the configuration of
network interfaces. It is expected that interface type specific network interfaces. It is expected that interface type specific
configuration data models augment the generic interfaces data model configuration data models augment the generic interfaces data model
defined in this document. defined in this document.
Status of this Memo Status of this Memo
skipping to change at page 1, line 33 skipping to change at page 1, line 33
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 10, 2012. This Internet-Draft will expire on August 11, 2012.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Interfaces Data Model . . . . . . . . . . . . . . . . . . . . 5 3. Interfaces Data Model . . . . . . . . . . . . . . . . . . . . 5
3.1. The interface List . . . . . . . . . . . . . . . . . . . . 5 3.1. The interface List . . . . . . . . . . . . . . . . . . . . 5
3.2. Interface References . . . . . . . . . . . . . . . . . . . 6 3.2. Interface References . . . . . . . . . . . . . . . . . . . 6
3.3. Interface Layering . . . . . . . . . . . . . . . . . . . . 6 3.3. Interface Layering . . . . . . . . . . . . . . . . . . . . 6
4. Interfaces YANG Module . . . . . . . . . . . . . . . . . . . . 7 4. Relationship to the IF-MIB . . . . . . . . . . . . . . . . . . 8
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 5. Interfaces YANG Module . . . . . . . . . . . . . . . . . . . . 9
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 14 7. Security Considerations . . . . . . . . . . . . . . . . . . . 15
8. Normative References . . . . . . . . . . . . . . . . . . . . . 15 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
Appendix A. Example: Ethernet Interface Module . . . . . . . . . 16 9. Normative References . . . . . . . . . . . . . . . . . . . . . 17
Appendix B. Example: Ethernet Bonding Interface Module . . . . . 18 Appendix A. Example: Ethernet Interface Module . . . . . . . . . 18
Appendix C. Example: VLAN Interface Module . . . . . . . . . . . 19 Appendix B. Example: Ethernet Bonding Interface Module . . . . . 20
Appendix D. Example: NETCONF <get> reply . . . . . . . . . . . . 20 Appendix C. Example: VLAN Interface Module . . . . . . . . . . . 21
Appendix E. ChangeLog . . . . . . . . . . . . . . . . . . . . . . 21 Appendix D. Example: NETCONF <get> reply . . . . . . . . . . . . 22
E.1. Version -02 . . . . . . . . . . . . . . . . . . . . . . . 21 Appendix E. ChangeLog . . . . . . . . . . . . . . . . . . . . . . 23
E.2. Version -01 . . . . . . . . . . . . . . . . . . . . . . . 21 E.1. Version -03 . . . . . . . . . . . . . . . . . . . . . . . 23
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 22 E.2. Version -02 . . . . . . . . . . . . . . . . . . . . . . . 23
E.3. Version -01 . . . . . . . . . . . . . . . . . . . . . . . 23
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 24
1. Introduction 1. Introduction
This document defines a YANG [RFC6020] data model for the This document defines a YANG [RFC6020] data model for the
configuration of network interfaces. It is expected that interface configuration of network interfaces. It is expected that interface
type specific configuration data models augment the generic type specific configuration data models augment the generic
interfaces data model defined in this document. interfaces data model defined in this document.
Network interfaces are central to the configuration of many Internet Network interfaces are central to the configuration of many Internet
protocols. Thus, it is important to establish a common data model protocols. Thus, it is important to establish a common data model
for how interfaces are identified and configured. for how interfaces are identified and configured.
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14, [RFC2119]. 14, [RFC2119].
2. Objectives 2. Objectives
This section describes some of the design objectives for the model This section describes some of the design objectives for the model
presented in Section 4. presented in Section 5.
o It is recognized that existing implementations will have to map o It is recognized that existing implementations will have to map
the interface data model defined in this memo to their proprietary the interface data model defined in this memo to their proprietary
native data model. The new data model should be simple to native data model. The new data model should be simple to
facilitate such mappings. facilitate such mappings.
o The data model should be suitable for new implementations to use o The data model should be suitable for new implementations to use
as-is, without requiring a mapping to a different native model. as-is, without requiring a mapping to a different native model.
o References to interfaces should be as simple as possible, o References to interfaces should be as simple as possible,
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o The data model should support the pre-provisioning of interface o The data model should support the pre-provisioning of interface
configuration, i.e., it should be possible to configure an configuration, i.e., it should be possible to configure an
interface whose physical interface hardware is not present on the interface whose physical interface hardware is not present on the
device. It is recommended that devices that support dynamic device. It is recommended that devices that support dynamic
addition and removal of physical interfaces also support pre- addition and removal of physical interfaces also support pre-
provisioning. provisioning.
3. Interfaces Data Model 3. Interfaces Data Model
The module "ietf-interfaces" has the following structure: The data model in the module "ietf-interfaces" has the following
structure, where square brackets are used to enclose a list's keys,
and "?" means that the leaf is optional:
+--rw interfaces +--rw interfaces
+--rw interface [name] +--rw interface [name]
+--rw name string +--rw name string
+--rw description? string +--rw description? string
+--rw type ianaift:iana-if-type +--rw type ianaift:iana-if-type
+--rw location? string +--rw location? string
+--rw enabled? boolean +--rw enabled? boolean
+--ro if-index* int32 +--ro if-index int32
+--rw mtu? uint32 +--rw mtu? uint32
+--rw link-up-down-trap-enable? enumeration +--rw link-up-down-trap-enable? enumeration
This module defines one YANG feature: This module defines one YANG feature:
snmp-if-mib: Indicates that the server implements IF-MIB [RFC2863]. snmp-if-mib: Indicates that the server implements IF-MIB [RFC2863].
3.1. The interface List 3.1. The interface List
The data model for interface configuration presented in this document The data model for interface configuration presented in this document
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type if:interface-ref; type if:interface-ref;
must "/if:interfaces/if:interface[if:name = current()]" must "/if:interfaces/if:interface[if:name = current()]"
+ "/if:type = 'ethernetCsmacd'" { + "/if:type = 'ethernetCsmacd'" {
description description
"The type of a slave interface must be ethernet"; "The type of a slave interface must be ethernet";
} }
} }
// other bonding config params, failover times etc. // other bonding config params, failover times etc.
} }
4. Interfaces YANG Module 4. Relationship to the IF-MIB
If the device implements IF-MIB [RFC2863], each entry in the
"interface" list is typically mapped to one ifEntry. The "if-index"
leaf contains the value of the corresponding ifEntry's ifIndex.
In most cases, the "name" of an "interface" entry is mapped to
ifName. ifName is defined as an DisplayString [RFC2579] which uses a
7-bit ASCII character set. An implementation MAY restrict the
allowed values for "name" to match the restrictions of ifName.
The IF-MIB allows two different ifEntries to have the same ifName.
Devices that support this feature, and also support the configuration
of these interfaces using the "interface" list, cannot have a 1-1
mapping between the "name" leaf and ifName.
5. Interfaces YANG Module
This YANG module imports a typedef from This YANG module imports a typedef from
[I-D.ietf-netmod-iana-if-type]. [I-D.ietf-netmod-iana-if-type].
RFC Ed.: update the date below with the date of RFC publication and RFC Ed.: update the date below with the date of RFC publication and
remove this note. remove this note.
<CODE BEGINS> file "ietf-interfaces@2011-09-07.yang" <CODE BEGINS> file "ietf-interfaces@2012-02-08.yang"
module ietf-interfaces { module ietf-interfaces {
namespace "urn:ietf:params:xml:ns:yang:ietf-interfaces"; namespace "urn:ietf:params:xml:ns:yang:ietf-interfaces";
prefix if; prefix if;
import iana-if-type { import iana-if-type {
prefix ianaift; prefix ianaift;
} }
skipping to change at page 8, line 12 skipping to change at page 10, line 12
Relating to IETF Documents Relating to IETF Documents
(http://trustee.ietf.org/license-info). (http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices."; the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this // RFC Ed.: replace XXXX with actual RFC number and remove this
// note. // note.
// RFC Ed.: update the date below with the date of RFC publication // RFC Ed.: update the date below with the date of RFC publication
// and remove this note. // and remove this note.
revision 2011-09-07 { revision 2012-02-08 {
description description
"Initial revision."; "Initial revision.";
reference reference
"RFC XXXX: A YANG Data Model for Interface Configuration"; "RFC XXXX: A YANG Data Model for Interface Configuration";
} }
/* Typedefs */ /* Typedefs */
typedef interface-ref { typedef interface-ref {
type leafref { type leafref {
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"Interface parameters."; "Interface parameters.";
list interface { list interface {
key "name"; key "name";
unique "type location"; unique "type location";
description description
"The list of configured interfaces on the device."; "The list of configured interfaces on the device.";
leaf name { leaf name {
type string { type string;
length "1..255";
}
description description
"An arbitrary name for the interface. "An arbitrary name for the interface.
A device MAY restrict the allowed values for this leaf, A device MAY restrict the allowed values for this leaf,
possibly depending on the type and location. possibly depending on the type and location.
For example, if a device has a single array of 8 ethernet For example, if a device has a single array of 8 ethernet
ports, the name might be restricted to be on the form ports, the name might be restricted to be on the form
'ethN', where N is an integer between '1' and '8'."; 'ethN', where N is an integer between '1' and '8'.
This leaf MAY be mapped to ifName by an implementation.
Such an implementation MAY restrict the allowed values
for this leaf so that it matches the restrictions of
ifName.";
reference
"RFC 2863: The Interfaces Group MIB - ifName";
} }
leaf description { leaf description {
type string; type string;
description description
"A textual description of the interface. "A textual description of the interface.
This leaf MAY be mapped to ifAlias by an implementation. This leaf MAY be mapped to ifAlias by an implementation.
Such an implementation MAY restrict the length of the Such an implementation MAY restrict the allowed values
value of this leaf so that it matches the restrictions for this leaf so that it matches the restrictions of
of ifAlias."; ifAlias.";
reference reference
"RFC 2863: The Interfaces Group MIB - ifAlias"; "RFC 2863: The Interfaces Group MIB - ifAlias";
} }
leaf type { leaf type {
type ianaift:iana-if-type; type ianaift:iana-if-type;
mandatory true; mandatory true;
description description
"The type of the interface. "The type of the interface.
skipping to change at page 10, line 25 skipping to change at page 12, line 30
} }
leaf enabled { leaf enabled {
type boolean; type boolean;
default "true"; default "true";
description description
"The desired state of the interface. "The desired state of the interface.
This leaf contains the configured, desired state of the This leaf contains the configured, desired state of the
interface. Systems that implement the IF-MIB use the interface. Systems that implement the IF-MIB use the
value of this leaf to set IF-MIB.ifAdminStatus after an value of this leaf to set IF-MIB.ifAdminStatus to 'up' or
ifEntry has been initialized, as described in RFC 2863."; 'down' after an ifEntry has been initialized, as described
in RFC 2863.";
reference reference
"RFC 2863: The Interfaces Group MIB - ifAdminStatus"; "RFC 2863: The Interfaces Group MIB - ifAdminStatus";
} }
leaf-list if-index { leaf if-index {
if-feature snmp-if-mib; if-feature snmp-if-mib;
type int32 { type int32 {
range "1..2147483647"; range "1..2147483647";
} }
config false; config false;
description description
"The list of ifIndex values for all ifEntries that are "The ifIndex value for the ifEntry represented by this
represented by this interface. If there is a one-to-one interface.
mapping between the interface and entries in the ifTable,
this leaf-list will have a single value.
Media-specific modules must specify how the type is Media-specific modules must specify how the type is
mapped to entries in the ifTable."; mapped to entries in the ifTable.";
reference reference
"RFC 2863: The Interfaces Group MIB - ifIndex"; "RFC 2863: The Interfaces Group MIB - ifIndex";
} }
leaf mtu { leaf mtu {
type uint32; type uint32;
description description
"The size, in octets, of the largest packet that the "The size, in octets, of the largest packet that the
interface can send and receive. This node might not be interface can send and receive. This node might not be
valid for all interface types. valid for all interface types.
Media-specific modules must specify any restrictions on Media-specific modules must specify any restrictions on
the mtu for their interface type."; the mtu for their interface type.";
} }
skipping to change at page 11, line 23 skipping to change at page 13, line 26
if-feature snmp-if-mib; if-feature snmp-if-mib;
type enumeration { type enumeration {
enum enabled { enum enabled {
value 1; value 1;
} }
enum disabled { enum disabled {
value 2; value 2;
} }
} }
description description
"Indicates whether linkUp/linkDown SNMP traps should be "Indicates whether linkUp/linkDown SNMP notifications
generated for this interface. should be generated for this interface.
If this node is not configured, the value 'enabled' is If this node is not configured, the value 'enabled' is
operationally used by the server for interfaces which do operationally used by the server for interfaces which do
not operate on top of any other intertface (as defined in not operate on top of any other interface (as defined in
the ifStackTable), and 'disabled' otherwise."; the ifStackTable), and 'disabled' otherwise.";
reference reference
"RFC 2863: The Interfaces Group MIB - "RFC 2863: The Interfaces Group MIB -
ifLinkUpDownTrapEnable"; ifLinkUpDownTrapEnable";
} }
} }
} }
} }
<CODE ENDS> <CODE ENDS>
5. IANA Considerations 6. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688]. This document registers a URI in the IETF XML registry [RFC3688].
Following the format in RFC 3688, the following registration is Following the format in RFC 3688, the following registration is
requested to be made. requested to be made.
URI: urn:ietf:params:xml:ns:yang:ietf-interfaces URI: urn:ietf:params:xml:ns:yang:ietf-interfaces
Registrant Contact: The NETMOD WG of the IETF. Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace. XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names This document registers a YANG module in the YANG Module Names
registry [RFC6020]. registry [RFC6020].
name: ietf-interfaces name: ietf-interfaces
namespace: urn:ietf:params:xml:ns:yang:ietf-interfaces namespace: urn:ietf:params:xml:ns:yang:ietf-interfaces
prefix: if prefix: if
reference: RFC XXXX reference: RFC XXXX
6. Security Considerations 7. Security Considerations
The YANG module defined in this memo is designed to be accessed via The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the
secure transport layer and the mandatory-to-implement secure secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242]. transport is SSH [RFC6242].
There are a number of data nodes defined in the YANG module which are There are a number of data nodes defined in the YANG module which are
writable/creatable/deletable (i.e., config true, which is the writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config) in some network environments. Write operations (e.g., edit-config)
skipping to change at page 14, line 5 skipping to change at page 16, line 5
and their sensitivity/vulnerability: and their sensitivity/vulnerability:
/interfaces/interface: This list specify the configured interfaces /interfaces/interface: This list specify the configured interfaces
on a device. Unauthorized access to this list could cause the on a device. Unauthorized access to this list could cause the
device to ignore packets destined to it. device to ignore packets destined to it.
/interfaces/interface/enabled: This leaf controls if an interface is /interfaces/interface/enabled: This leaf controls if an interface is
enabled or not. Unauthorized access to this leaf could cause the enabled or not. Unauthorized access to this leaf could cause the
device to ignore packets destined to it. device to ignore packets destined to it.
7. Acknowledgments 8. Acknowledgments
The author wishes to thank Per Hedeland, Ladislav Lhotka, and Juergen The author wishes to thank Per Hedeland, Ladislav Lhotka, and Juergen
Schoenwaelder for their helpful comments. Schoenwaelder for their helpful comments.
8. Normative References 9. Normative References
[I-D.ietf-netmod-iana-if-type] [I-D.ietf-netmod-iana-if-type]
Bjorklund, M., "IANA Interface Type YANG Module", Bjorklund, M., "IANA Interface Type YANG Module",
draft-ietf-netmod-iana-if-type-00 (work in progress), draft-ietf-netmod-iana-if-type-00 (work in progress),
April 2011. April 2011.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Textual Conventions for SMIv2",
STD 58, RFC 2579, April 1999.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group [RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, June 2000. MIB", RFC 2863, June 2000.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004. January 2004.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020, Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010. October 2010.
skipping to change at page 20, line 7 skipping to change at page 22, line 7
type uint16 { type uint16 {
range "1..4094"; range "1..4094";
} }
must "../base-interface"; must "../base-interface";
} }
} }
} }
Appendix D. Example: NETCONF <get> reply Appendix D. Example: NETCONF <get> reply
This section gives an example of a reply to the NETCOMF <get> request This section gives an example of a reply to the NETCONF <get> request
for a device that implements the example data models above. for a device that implements the example data models above.
<rpc-reply <rpc-reply
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
message-id="101"> message-id="101">
<data> <data>
<interfaces <interfaces
xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"> xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface> <interface>
<name>eth0</name> <name>eth0</name>
<type>ethernetCsmacd</type> <type>ethernetCsmacd</type>
<location>0</location> <location>0</location>
<enabled>true</enabled> <enabled>true</enabled>
<if-index>2</if-index> <if-index>2</if-index>
<ip xmlns="http://example.com/ip">
<address>
<ip>192.0.2.1</ip>
<prefix-length>24</prefix-length>
</address>
</ip>
</interface> </interface>
<interface> <interface>
<name>eth1</name> <name>eth1</name>
<type>ethernetCsmacd</type> <type>ethernetCsmacd</type>
<location>1</location> <location>1</location>
<enabled>true</enabled> <enabled>true</enabled>
<if-index>7</if-index> <if-index>7</if-index>
<ip xmlns="http://example.com/ip"> <vlan-tagging
<address> xmlns="http://example.com/vlan">true</vlan-tagging>
<ip>192.168.1.1</ip>
<prefix-length>24</prefix-length>
</address>
</ip>
</interface> </interface>
</interfaces> </interfaces>
</data> </data>
</rpc-reply> </rpc-reply>
Appendix E. ChangeLog Appendix E. ChangeLog
RFC Editor: remove this section upon publication as an RFC. RFC Editor: remove this section upon publication as an RFC.
E.1. Version -02 E.1. Version -03
o Added the section Relationship to the IF-MIB.
o Changed if-index to be a leaf instead of leaf-list.
o Explained the notation used in the data model tree picture.
E.2. Version -02
o Editorial fixes o Editorial fixes
E.2. Version -01 E.3. Version -01
o Changed leaf "if-admin-status" to leaf "enabled". o Changed leaf "if-admin-status" to leaf "enabled".
o Added Security Considerations o Added Security Considerations
Author's Address Author's Address
Martin Bjorklund Martin Bjorklund
Tail-f Systems Tail-f Systems
 End of changes. 31 change blocks. 
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