Internet Engineering Task Force (IETF) M. Bjorklund Request for Comments: 8343 Tail-f Systems Obsoletes: 7223 March 2018 Category: Standards Track ISSN: 2070-1721
A YANG Data Model for Interface Management
Abstract
This document defines a YANG data model for the management of network interfaces. It is expected that interface-type-specific data models augment the generic interfaces data model defined in this document. The data model includes definitions for configuration and system state (status information and counters for the collection of statistics).
The YANG data model in this document conforms to the Network Management Datastore Architecture (NMDA) defined in RFC 8342.
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8343.
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Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
Table of Contents
1. Introduction ....................................................3 1.1. Summary of Changes from RFC 7223 ...........................3 1.2. Terminology ................................................3 1.3. Tree Diagrams ..............................................4 2. Objectives ......................................................5 3. Interfaces Data Model ...........................................5 3.1. The Interface List .........................................6 3.2. Interface References .......................................8 3.3. Interface Layering .........................................8 4. Relationship to the IF-MIB ......................................9 5. Interfaces YANG Module .........................................10 6. IANA Considerations ............................................34 7. Security Considerations ........................................35 8. References .....................................................36 8.1. Normative References ......................................36 8.2. Informative References ....................................37 Appendix A. Example: Ethernet Interface Module ...................38 Appendix B. Example: Ethernet Bonding Interface Module ...........39 Appendix C. Example: VLAN Interface Module .......................40 Appendix D. Example: NETCONF <get-config> Reply ..................41 Appendix E. Example: NETCONF <get-data> Reply ....................42 Appendix F. Examples: Interface Naming Schemes ...................44 F.1. Router with Restricted Interface Names ....................44 F.2. Router with Arbitrary Interface Names .....................45 F.3. Ethernet Switch with Restricted Interface Names ...........46 F.4. Generic Host with Restricted Interface Names ..............47 F.5. Generic Host with Arbitrary Interface Names ...............48 Acknowledgments ...................................................49 Author's Address ..................................................49
This document defines a YANG data model [RFC7950] for the management of network interfaces. It is expected that interface-type-specific data models will augment the generic interfaces data model defined in this document.
Network interfaces are central to the management of many Internet protocols. Thus, it is important to establish a common data model for how interfaces are identified, configured, and monitored.
The data model includes configuration data and state data (status information and counters for the collection of statistics).
This version of the interfaces data model supports the Network Management Datastore Architecture (NMDA) [RFC8342].
The "/interfaces-state" subtree with "config false" data nodes is deprecated. All "config false" data nodes are now present in the "/interfaces" subtree.
Servers that do not implement NMDA, or that wish to support clients that do not implement NMDA, MAY implement the deprecated "/interfaces-state" tree.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.
The following terms are used within this document:
o system-controlled interface: An interface is said to be system- controlled if the system creates and deletes the interface independently of what has been explicitly configured. Examples are interfaces representing physical hardware that appear and disappear when hardware (e.g., a line card or hot-pluggable wireless interface) is added or removed. System-controlled interfaces may also appear if a certain functionality is enabled (e.g., a loopback interface might appear if the IP protocol stack is enabled).
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o user-controlled interface: An interface is said to be user- controlled if the creation of the interface is controlled by adding explicit interface configuration to the intended configuration and the removal of the interface is controlled by removing explicit interface configuration from the intended configuration. Examples are VLAN interfaces configured on a system-controlled Ethernet interface.
The following terms are defined in [RFC8342] and are not redefined here:
o client
o server
o configuration
o system state
o operational state
o intended configuration
o running configuration datastore
o operational state datastore
The following terms are defined in [RFC7950] and are not redefined here:
This section describes some of the design objectives for the model presented in Section 5.
o It is recognized that existing implementations will have to map the interface data model defined in this memo to their proprietary native data model. To facilitate such mappings, the data model should be simple.
o The data model should be suitable for new implementations to use as is, without requiring a mapping to a different native model.
o References to interfaces should be as simple as possible, preferably by using a single leafref.
o The mapping to ifIndex [RFC2863] used by the Simple Network Management Protocol (SNMP) to identify interfaces must be clear.
o The model must support interface layering: both (1) simple layering, where one interface is layered on top of exactly one other interface, and (2) more complex scenarios, where one interface results from the aggregation of N other interfaces or when N interfaces are multiplexed over one other interface.
o The data model should support the pre-provisioning of interface configuration; that is, it should be possible to configure an interface whose physical interface hardware is not present on the device. It is recommended that devices that support dynamic addition and removal of physical interfaces also support pre-provisioning.
o The data model should support physical interfaces as well as logical interfaces.
o The data model should include read-only counters in order to gather statistics for sent and received octets and packets, received packets with errors, and packets that could not be sent due to errors.
The data model for interfaces presented in this document uses a flat list of interfaces ("/interfaces/interface"). Each interface in the list is identified by its name. Furthermore, each interface has a mandatory "type" leaf.
The "iana-if-type" module [RFC7224] defines YANG identities for the interface types in the IANA-maintained "ifType definitions" registry.
It is expected that interface-type-specific data models augment the interface list and possibly use the "type" leaf to make the augmentation conditional.
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As an example of such an interface-type-specific augmentation, consider this YANG snippet. For a more complete example, see Appendix A.
augment "/if:interfaces/if:interface" { when "if:type = 'ianaift:ethernetCsmacd'";
container ethernet { leaf duplex { ... } } }
For system-controlled interfaces, the "name" is the device-specific name of the interface.
If the device supports arbitrarily named user-controlled interfaces, then the server will advertise the "arbitrary-names" feature. If the server does not advertise this feature, the names of user-controlled interfaces MUST match the device's naming scheme. How a client can learn the naming scheme of such devices is outside the scope of this document. See Appendices F.1 and F.2 for examples.
When a system-controlled interface is created in the operational state by the system, the system tries to apply the interface configuration in the intended configuration with the same name as the new interface. If no such interface configuration is found, or if the configured type does not match the real interface type, the system creates the interface without applying explicit configuration.
When a user-controlled interface is created, the configuration determines the name of the interface.
Depending on the operating system and the physical attachment point to which a network interface may be attached or removed, it may be impossible for an implementation to provide predictable and consistent names for system-controlled interfaces across insertion/ removal cycles as well as in anticipation of initial insertion. The ability to provide configurations for such interfaces is therefore dependent on the implementation and cannot be assumed in all cases.
An interface is identified by its name, which is unique within the server. This property is captured in the "interface-ref" typedef, which other YANG modules SHOULD use when they need to reference an interface.
There is no generic mechanism for how an interface is configured to be layered on top of some other interface. It is expected that interface-type-specific models define their own data nodes for interface layering by using "interface-ref" types to reference lower layers.
Below is an example of a model with such nodes. For a more complete example, see Appendix B.
augment "/if:interfaces/if:interface" { when "if:type = 'ianaift:ieee8023adLag'";
leaf-list slave-if { type if:interface-ref; must "/if:interfaces/if:interface[if:name = current()]" + "/if:type = 'ianaift:ethernetCsmacd'" { description "The type of a slave interface must be 'ethernetCsmacd'."; } } // other bonding config params, failover times, etc. }
While the interface layering is configured in interface-type-specific models, two generic state data leaf-lists, "higher-layer-if" and "lower-layer-if", represent a read-only view of the interface layering hierarchy.
If the device implements the IF-MIB [RFC2863], each entry in the "/interfaces/interface" list in the operational state is typically mapped to one ifEntry. The "if-index" leaf MUST contain the value of the corresponding ifEntry's ifIndex.
In most cases, the "name" of an "/interfaces/interface" entry is mapped to ifName. The IF-MIB allows two different ifEntries to have the same ifName. Devices that support this feature and also support the data model defined in this document cannot have a 1-1 mapping between the "name" leaf and ifName.
The configured "description" of an "interface" has traditionally been mapped to ifAlias in some implementations. This document allows this mapping, but implementers should be aware of the differences in the value space and persistence for these objects. See the YANG module definition of the leaf "description" in Section 5 for details.
The IF-MIB also defines the writable object ifPromiscuousMode. Since this object typically is not implemented as a configuration object by SNMP agents, it is not mapped to the "ietf-interfaces" module.
The ifMtu object from the IF-MIB is not mapped to the "ietf-interfaces" module. It is expected that interface-type- specific YANG modules provide interface-type-specific MTU leafs by augmenting the "ietf-interfaces" model.
There are a number of counters in the IF-MIB that exist in two versions: one with 32 bits and one with 64 bits. The 64-bit versions were added to support high-speed interfaces with a data rate greater than 20,000,000 bits/second. Today's implementations generally support such high-speed interfaces; hence, only 64-bit counters are provided in this data model. Note that the server that implements this module and an SNMP agent may differ in the time granularity in which they provide access to the counters. For example, it is common that SNMP implementations cache counter values for some time.
The objects ifDescr and ifConnectorPresent from the IF-MIB are not mapped to the "ietf-interfaces" module.
The following table lists the YANG data nodes with corresponding objects in the IF-MIB.
Editor: Martin Bjorklund <mailto:mbj@tail-f.com>";
description "This module contains a collection of YANG definitions for managing network interfaces.
Copyright (c) 2018 IETF Trust and the persons identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC 8343; see the RFC itself for full legal notices.";
revision 2018-02-20 { description "Updated to support NMDA."; reference "RFC 8343: A YANG Data Model for Interface Management"; }
revision 2014-05-08 { description "Initial revision."; reference "RFC 7223: A YANG Data Model for Interface Management"; }
/* * Typedefs */
typedef interface-ref { type leafref { path "/if:interfaces/if:interface/if:name";
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} description "This type is used by data models that need to reference interfaces."; }
/* * Identities */
identity interface-type { description "Base identity from which specific interface types are derived."; }
/* * Features */
feature arbitrary-names { description "This feature indicates that the device allows user-controlled interfaces to be named arbitrarily."; } feature pre-provisioning { description "This feature indicates that the device supports pre-provisioning of interface configuration, i.e., it is possible to configure an interface whose physical interface hardware is not present on the device."; } feature if-mib { description "This feature indicates that the device implements the IF-MIB."; reference "RFC 2863: The Interfaces Group MIB"; }
description "The list of interfaces on the device.
The status of an interface is available in this list in the operational state. If the configuration of a system-controlled interface cannot be used by the system (e.g., the interface hardware present does not match the interface type), then the configuration is not applied to the system-controlled interface shown in the operational state. If the configuration of a user-controlled interface cannot be used by the system, the configured interface is not instantiated in the operational state.
System-controlled interfaces created by the system are always present in this list in the operational state, whether or not they are configured.";
leaf name { type string; description "The name of the interface.
A device MAY restrict the allowed values for this leaf, possibly depending on the type of the interface. For system-controlled interfaces, this leaf is the device-specific name of the interface.
If a client tries to create configuration for a system-controlled interface that is not present in the operational state, the server MAY reject the request if the implementation does not support pre-provisioning of interfaces or if the name refers to an interface that can never exist in the system. A Network Configuration Protocol (NETCONF) server MUST reply with an rpc-error with the error-tag 'invalid-value' in this case.
If the device supports pre-provisioning of interface configuration, the 'pre-provisioning' feature is advertised.
If the device allows arbitrarily named user-controlled interfaces, the 'arbitrary-names' feature is advertised.
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When a configured user-controlled interface is created by the system, it is instantiated with the same name in the operational state.
A server implementation MAY map this leaf to the ifName MIB object. Such an implementation needs to use some mechanism to handle the differences in size and characters allowed between this leaf and ifName. The definition of such a mechanism is outside the scope of this document."; reference "RFC 2863: The Interfaces Group MIB - ifName"; }
leaf description { type string; description "A textual description of the interface.
A server implementation MAY map this leaf to the ifAlias MIB object. Such an implementation needs to use some mechanism to handle the differences in size and characters allowed between this leaf and ifAlias. The definition of such a mechanism is outside the scope of this document.
Since ifAlias is defined to be stored in non-volatile storage, the MIB implementation MUST map ifAlias to the value of 'description' in the persistently stored configuration."; reference "RFC 2863: The Interfaces Group MIB - ifAlias"; }
leaf type { type identityref { base interface-type; } mandatory true; description "The type of the interface.
When an interface entry is created, a server MAY initialize the type leaf with a valid value, e.g., if it is possible to derive the type from the name of the interface.
If a client tries to set the type of an interface to a value that can never be used by the system, e.g., if the type is not supported or if the type does not match the
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name of the interface, the server MUST reject the request. A NETCONF server MUST reply with an rpc-error with the error-tag 'invalid-value' in this case."; reference "RFC 2863: The Interfaces Group MIB - ifType"; }
leaf enabled { type boolean; default "true"; description "This leaf contains the configured, desired state of the interface.
Systems that implement the IF-MIB use the value of this leaf in the intended configuration to set IF-MIB.ifAdminStatus to 'up' or 'down' after an ifEntry has been initialized, as described in RFC 2863.
Changes in this leaf in the intended configuration are reflected in ifAdminStatus."; reference "RFC 2863: The Interfaces Group MIB - ifAdminStatus"; }
leaf link-up-down-trap-enable { if-feature if-mib; type enumeration { enum enabled { value 1; description "The device will generate linkUp/linkDown SNMP notifications for this interface."; } enum disabled { value 2; description "The device will not generate linkUp/linkDown SNMP notifications for this interface."; } } description "Controls whether linkUp/linkDown SNMP notifications should be generated for this interface.
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If this node is not configured, the value 'enabled' is operationally used by the server for interfaces that do not operate on top of any other interface (i.e., there are no 'lower-layer-if' entries), and 'disabled' otherwise."; reference "RFC 2863: The Interfaces Group MIB - ifLinkUpDownTrapEnable"; }
leaf admin-status { if-feature if-mib; type enumeration { enum up { value 1; description "Ready to pass packets."; } enum down { value 2; description "Not ready to pass packets and not in some test mode."; } enum testing { value 3; description "In some test mode."; } } config false; mandatory true; description "The desired state of the interface.
This leaf has the same read semantics as ifAdminStatus."; reference "RFC 2863: The Interfaces Group MIB - ifAdminStatus"; }
leaf oper-status { type enumeration { enum up { value 1; description "Ready to pass packets."; } enum down { value 2;
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description "The interface does not pass any packets."; } enum testing { value 3; description "In some test mode. No operational packets can be passed."; } enum unknown { value 4; description "Status cannot be determined for some reason."; } enum dormant { value 5; description "Waiting for some external event."; } enum not-present { value 6; description "Some component (typically hardware) is missing."; } enum lower-layer-down { value 7; description "Down due to state of lower-layer interface(s)."; } } config false; mandatory true; description "The current operational state of the interface.
This leaf has the same semantics as ifOperStatus."; reference "RFC 2863: The Interfaces Group MIB - ifOperStatus"; }
leaf last-change { type yang:date-and-time; config false; description "The time the interface entered its current operational state. If the current state was entered prior to the last re-initialization of the local network management subsystem, then this node is not present.";
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reference "RFC 2863: The Interfaces Group MIB - ifLastChange"; }
leaf if-index { if-feature if-mib; type int32 { range "1..2147483647"; } config false; mandatory true; description "The ifIndex value for the ifEntry represented by this interface."; reference "RFC 2863: The Interfaces Group MIB - ifIndex"; }
leaf phys-address { type yang:phys-address; config false; description "The interface's address at its protocol sub-layer. For example, for an 802.x interface, this object normally contains a Media Access Control (MAC) address. The interface's media-specific modules must define the bit and byte ordering and the format of the value of this object. For interfaces that do not have such an address (e.g., a serial line), this node is not present."; reference "RFC 2863: The Interfaces Group MIB - ifPhysAddress"; }
leaf-list higher-layer-if { type interface-ref; config false; description "A list of references to interfaces layered on top of this interface."; reference "RFC 2863: The Interfaces Group MIB - ifStackTable"; }
leaf-list lower-layer-if { type interface-ref; config false;
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description "A list of references to interfaces layered underneath this interface."; reference "RFC 2863: The Interfaces Group MIB - ifStackTable"; }
leaf speed { type yang:gauge64; units "bits/second"; config false; description "An estimate of the interface's current bandwidth in bits per second. For interfaces that do not vary in bandwidth or for those where no accurate estimation can be made, this node should contain the nominal bandwidth. For interfaces that have no concept of bandwidth, this node is not present."; reference "RFC 2863: The Interfaces Group MIB - ifSpeed, ifHighSpeed"; }
container statistics { config false; description "A collection of interface-related statistics objects.";
leaf discontinuity-time { type yang:date-and-time; mandatory true; description "The time on the most recent occasion at which any one or more of this interface's counters suffered a discontinuity. If no such discontinuities have occurred since the last re-initialization of the local management subsystem, then this node contains the time the local management subsystem re-initialized itself."; }
leaf in-octets { type yang:counter64; description "The total number of octets received on the interface, including framing characters.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInOctets"; }
leaf in-unicast-pkts { type yang:counter64; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were not addressed to a multicast or broadcast address at this sub-layer.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInUcastPkts"; }
leaf in-broadcast-pkts { type yang:counter64; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were addressed to a broadcast address at this sub-layer.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInBroadcastPkts"; }
leaf in-multicast-pkts { type yang:counter64; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were addressed to a multicast address at this sub-layer. For a MAC-layer protocol, this includes both Group and Functional addresses.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInMulticastPkts"; }
leaf in-discards { type yang:counter32; description "The number of inbound packets that were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInDiscards"; }
leaf in-errors { type yang:counter32; description "For packet-oriented interfaces, the number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol. For character- oriented or fixed-length interfaces, the number of inbound transmission units that contained errors preventing them from being deliverable to a higher-layer protocol.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInErrors"; }
leaf in-unknown-protos { type yang:counter32;
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description "For packet-oriented interfaces, the number of packets received via the interface that were discarded because of an unknown or unsupported protocol. For character-oriented or fixed-length interfaces that support protocol multiplexing, the number of transmission units received via the interface that were discarded because of an unknown or unsupported protocol. For any interface that does not support protocol multiplexing, this counter is not present.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInUnknownProtos"; }
leaf out-octets { type yang:counter64; description "The total number of octets transmitted out of the interface, including framing characters.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutOctets"; }
leaf out-unicast-pkts { type yang:counter64; description "The total number of packets that higher-level protocols requested be transmitted and that were not addressed to a multicast or broadcast address at this sub-layer, including those that were discarded or not sent.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutUcastPkts";
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}
leaf out-broadcast-pkts { type yang:counter64; description "The total number of packets that higher-level protocols requested be transmitted and that were addressed to a broadcast address at this sub-layer, including those that were discarded or not sent.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutBroadcastPkts"; }
leaf out-multicast-pkts { type yang:counter64; description "The total number of packets that higher-level protocols requested be transmitted and that were addressed to a multicast address at this sub-layer, including those that were discarded or not sent. For a MAC-layer protocol, this includes both Group and Functional addresses.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutMulticastPkts"; }
leaf out-discards { type yang:counter32; description "The number of outbound packets that were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a packet could be to free up buffer space.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifOutDiscards"; }
leaf out-errors { type yang:counter32; description "For packet-oriented interfaces, the number of outbound packets that could not be transmitted because of errors. For character-oriented or fixed-length interfaces, the number of outbound transmission units that could not be transmitted because of errors.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifOutErrors"; } }
} }
/* * Legacy typedefs */
typedef interface-state-ref { type leafref { path "/if:interfaces-state/if:interface/if:name"; } status deprecated; description "This type is used by data models that need to reference the operationally present interfaces."; }
/* * Legacy operational state data nodes */
container interfaces-state {
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config false; status deprecated; description "Data nodes for the operational state of interfaces.";
list interface { key "name"; status deprecated;
description "The list of interfaces on the device.
System-controlled interfaces created by the system are always present in this list, whether or not they are configured.";
leaf name { type string; status deprecated; description "The name of the interface.
A server implementation MAY map this leaf to the ifName MIB object. Such an implementation needs to use some mechanism to handle the differences in size and characters allowed between this leaf and ifName. The definition of such a mechanism is outside the scope of this document."; reference "RFC 2863: The Interfaces Group MIB - ifName"; }
leaf type { type identityref { base interface-type; } mandatory true; status deprecated; description "The type of the interface."; reference "RFC 2863: The Interfaces Group MIB - ifType"; }
leaf admin-status { if-feature if-mib; type enumeration { enum up { value 1;
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description "Ready to pass packets."; } enum down { value 2; description "Not ready to pass packets and not in some test mode."; } enum testing { value 3; description "In some test mode."; } } mandatory true; status deprecated; description "The desired state of the interface.
This leaf has the same read semantics as ifAdminStatus."; reference "RFC 2863: The Interfaces Group MIB - ifAdminStatus"; }
leaf oper-status { type enumeration { enum up { value 1; description "Ready to pass packets."; } enum down { value 2; description "The interface does not pass any packets."; } enum testing { value 3; description "In some test mode. No operational packets can be passed."; } enum unknown { value 4; description "Status cannot be determined for some reason."; } enum dormant {
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value 5; description "Waiting for some external event."; } enum not-present { value 6; description "Some component (typically hardware) is missing."; } enum lower-layer-down { value 7; description "Down due to state of lower-layer interface(s)."; } } mandatory true; status deprecated; description "The current operational state of the interface.
This leaf has the same semantics as ifOperStatus."; reference "RFC 2863: The Interfaces Group MIB - ifOperStatus"; }
leaf last-change { type yang:date-and-time; status deprecated; description "The time the interface entered its current operational state. If the current state was entered prior to the last re-initialization of the local network management subsystem, then this node is not present."; reference "RFC 2863: The Interfaces Group MIB - ifLastChange"; }
leaf if-index { if-feature if-mib; type int32 { range "1..2147483647"; } mandatory true; status deprecated; description "The ifIndex value for the ifEntry represented by this interface.";
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reference "RFC 2863: The Interfaces Group MIB - ifIndex"; }
leaf phys-address { type yang:phys-address; status deprecated; description "The interface's address at its protocol sub-layer. For example, for an 802.x interface, this object normally contains a Media Access Control (MAC) address. The interface's media-specific modules must define the bit and byte ordering and the format of the value of this object. For interfaces that do not have such an address (e.g., a serial line), this node is not present."; reference "RFC 2863: The Interfaces Group MIB - ifPhysAddress"; }
leaf-list higher-layer-if { type interface-state-ref; status deprecated; description "A list of references to interfaces layered on top of this interface."; reference "RFC 2863: The Interfaces Group MIB - ifStackTable"; }
leaf-list lower-layer-if { type interface-state-ref; status deprecated; description "A list of references to interfaces layered underneath this interface."; reference "RFC 2863: The Interfaces Group MIB - ifStackTable"; }
leaf speed { type yang:gauge64; units "bits/second"; status deprecated; description "An estimate of the interface's current bandwidth in bits per second. For interfaces that do not vary in bandwidth or for those where no accurate estimation can
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be made, this node should contain the nominal bandwidth. For interfaces that have no concept of bandwidth, this node is not present."; reference "RFC 2863: The Interfaces Group MIB - ifSpeed, ifHighSpeed"; }
container statistics { status deprecated; description "A collection of interface-related statistics objects.";
leaf discontinuity-time { type yang:date-and-time; mandatory true; status deprecated; description "The time on the most recent occasion at which any one or more of this interface's counters suffered a discontinuity. If no such discontinuities have occurred since the last re-initialization of the local management subsystem, then this node contains the time the local management subsystem re-initialized itself."; }
leaf in-octets { type yang:counter64; status deprecated; description "The total number of octets received on the interface, including framing characters.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInOctets"; }
leaf in-unicast-pkts { type yang:counter64; status deprecated; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were not addressed to a multicast or broadcast address at this sub-layer.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInUcastPkts"; }
leaf in-broadcast-pkts { type yang:counter64; status deprecated; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were addressed to a broadcast address at this sub-layer.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInBroadcastPkts"; }
leaf in-multicast-pkts { type yang:counter64; status deprecated; description "The number of packets, delivered by this sub-layer to a higher (sub-)layer, that were addressed to a multicast address at this sub-layer. For a MAC-layer protocol, this includes both Group and Functional addresses.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCInMulticastPkts"; }
leaf in-discards { type yang:counter32; status deprecated;
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description "The number of inbound packets that were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInDiscards"; }
leaf in-errors { type yang:counter32; status deprecated; description "For packet-oriented interfaces, the number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol. For character- oriented or fixed-length interfaces, the number of inbound transmission units that contained errors preventing them from being deliverable to a higher-layer protocol.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInErrors"; }
leaf in-unknown-protos { type yang:counter32; status deprecated; description "For packet-oriented interfaces, the number of packets received via the interface that were discarded because of an unknown or unsupported protocol. For character-oriented or fixed-length interfaces that support protocol multiplexing, the number of transmission units received via the interface that were discarded because of an unknown or unsupported protocol. For any interface that does not support protocol multiplexing, this counter is not present.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifInUnknownProtos"; }
leaf out-octets { type yang:counter64; status deprecated; description "The total number of octets transmitted out of the interface, including framing characters.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutOctets"; }
leaf out-unicast-pkts { type yang:counter64; status deprecated; description "The total number of packets that higher-level protocols requested be transmitted and that were not addressed to a multicast or broadcast address at this sub-layer, including those that were discarded or not sent.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutUcastPkts"; }
leaf out-broadcast-pkts { type yang:counter64; status deprecated;
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description "The total number of packets that higher-level protocols requested be transmitted and that were addressed to a broadcast address at this sub-layer, including those that were discarded or not sent.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutBroadcastPkts"; }
leaf out-multicast-pkts { type yang:counter64; status deprecated; description "The total number of packets that higher-level protocols requested be transmitted and that were addressed to a multicast address at this sub-layer, including those that were discarded or not sent. For a MAC-layer protocol, this includes both Group and Functional addresses.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifHCOutMulticastPkts"; }
leaf out-discards { type yang:counter32; status deprecated; description "The number of outbound packets that were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a packet could be to free up buffer space.
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Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifOutDiscards"; }
leaf out-errors { type yang:counter32; status deprecated; description "For packet-oriented interfaces, the number of outbound packets that could not be transmitted because of errors. For character-oriented or fixed-length interfaces, the number of outbound transmission units that could not be transmitted because of errors.
Discontinuities in the value of this counter can occur at re-initialization of the management system and at other times as indicated by the value of 'discontinuity-time'."; reference "RFC 2863: The Interfaces Group MIB - ifOutErrors"; } } } } }
The YANG module specified in this document defines a schema for data that is designed to be accessed via network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure transport is TLS [RFC5246].
The NETCONF access control model [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content.
There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability:
/interfaces/interface: This list specifies the configured interfaces on a device. Unauthorized access to this list could cause the device to ignore packets it should receive and process.
/interfaces/interface/enabled: This leaf controls whether or not an interface is enabled. Unauthorized access to this leaf could cause the device to ignore packets it should receive and process.
This section gives a simple example of how an Ethernet interface module could be defined. It demonstrates how media-specific configuration parameters can be conditionally augmented to the generic interface list. It also shows how operational state parameters can be conditionally augmented to the operational interface list. The example is not intended as a complete module for Ethernet configuration.
Appendix B. Example: Ethernet Bonding Interface Module
This section gives an example of how interface layering can be defined. An Ethernet bonding interface that bonds several Ethernet interfaces into one logical interface is defined.
augment "/if:interfaces/if:interface" { when "if:type = 'ianaift:ieee8023adLag'";
leaf-list slave-if { type if:interface-ref; must "/if:interfaces/if:interface[if:name = current()]" + "/if:type = 'ianaift:ethernetCsmacd'" { description "The type of a slave interface must be 'ethernetCsmacd'."; } } leaf bonding-mode { type enumeration { enum round-robin;
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enum active-backup; enum broadcast; } } // other bonding config params, failover times, etc. } }
augment "/if:interfaces/if:interface" { when "if:type = 'ianaift:ethernetCsmacd' or if:type = 'ianaift:ieee8023adLag'"; leaf vlan-tagging { type boolean; default false; } }
augment "/if:interfaces/if:interface" { when "if:type = 'ianaift:l2vlan'";
leaf base-interface { type if:interface-ref; must "/if:interfaces/if:interface[if:name = current()]" + "/vlan:vlan-tagging = 'true'" { description "The base interface must have VLAN tagging enabled."; } } leaf vlan-id { type uint16 { range "1..4094"; }
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must "../base-interface" { description "If a vlan-id is defined, a base-interface must be specified."; } } } }
This section gives an example of a reply to the NETCONF <get-config> request for the running configuration datastore for a device that implements the example data models above.
This section gives an example of a reply to the NETCONF <get-data> request for the operational state datastore for a device that implements the example data models above.
This example uses the "origin" annotation, which is defined in the module "ietf-origin" [RFC8342].
In this example, a router has support for 4 line cards, each with 8 ports. The slots for the cards are physically numbered from 0 to 3, and the ports on each card from 0 to 7. Each card has Fast Ethernet or Gigabit Ethernet ports.
The device-specific names for these physical interfaces are "fastethernet-N/M" or "gigabitethernet-N/M".
The name of a VLAN interface is restricted to the form "<physical-interface-name>.<subinterface-number>".
It is assumed that the operator is aware of this naming scheme. The implementation auto-initializes the value for "type" based on the interface name.
The NETCONF server does not advertise the "arbitrary-names" feature in the <hello> message.
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An operator can configure a physical interface by sending an <edit-config> containing:
When the server processes this request, it will set the leaf "type" to "ianaift:ethernetCsmacd". Thus, if the client performs a <get-config> right after the <edit-config> above, it will get:
In this example, a router has support for 4 line cards, each with 8 ports. The slots for the cards are physically numbered from 0 to 3, and the ports on each card from 0 to 7. Each card has Fast Ethernet or Gigabit Ethernet ports.
The device-specific names for these physical interfaces are "fastethernet-N/M" or "gigabitethernet-N/M".
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The implementation does not restrict the user-controlled interface names. This allows an operator to more easily apply the interface configuration to a different interface. However, the additional level of indirection also makes it a bit more complex to map interface names found in other protocols to configuration entries.
The NETCONF server advertises the "arbitrary-names" feature in the <hello> message.
Physical interfaces are configured as in Appendix F.1.
An operator can configure a VLAN interface by sending an <edit-config> containing:
When the server processes this request, it will set the leaf "type" to "ianaift:ethernetCsmacd". Thus, if the client performs a <get-config> right after the <edit-config> above, it will get:
In this example, a generic host has interfaces named by the kernel. The system identifies the physical interface by the name assigned by the operating system to the interface.
The name of a VLAN interface is restricted to the form "<physical-interface-name>:<vlan-number>".
The NETCONF server does not advertise the "arbitrary-names" feature in the <hello> message.
An operator can configure an interface by sending an <edit-config> containing:
When the server processes this request, it will set the leaf "type" to "ianaift:ethernetCsmacd". Thus, if the client performs a <get-config> right after the <edit-config> above, it will get:
In this example, a generic host has interfaces named by the kernel. The system identifies the physical interface by the name assigned by the operating system to the interface.
The implementation does not restrict the user-controlled interface names. This allows an operator to more easily apply the interface configuration to a different interface. However, the additional level of indirection also makes it a bit more complex to map interface names found in other protocols to configuration entries.
The NETCONF server advertises the "arbitrary-names" feature in the <hello> message.
Physical interfaces are configured as in Appendix F.4.
An operator can configure a VLAN interface by sending an <edit-config> containing: