Network Working Group J. Schoenwaelder, Ed. Internet-Draft Jacobs University Intended status: Standards Track November 8, 2010 Expires: May 12, 2011 Translation of SMIv2 MIB Modules to YANG Modules draft-schoenw-netmod-smi-yang-01 Abstract YANG is a data modeling language used to model configuration and state data manipulated by the NETCONF protocol, NETCONF remote procedure calls, and NETCONF notifications. The Structure of Management Information (SMIv2) defines fundamental data types, an object model, and the rules for writing and revising MIB modules for use with the SNMP protocol. This document defines a translation of SMIv2 MIB modules into YANG modules. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on May 12, 2011. Copyright Notice Copyright (c) 2010 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 (http://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 Schoenwaelder Expires May 12, 2011 [Page 1] Internet-Draft Translation of SMIv2 to YANG November 2010 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Translation of SMIv2 to YANG . . . . . . . . . . . . . . . . . 4 2.1. Mapping of Special Types . . . . . . . . . . . . . . . . . 4 2.2. Module Prefix Generation . . . . . . . . . . . . . . . . . 5 2.3. Translation of SMIv2 Modules . . . . . . . . . . . . . . . 5 2.4. Translation of SMIv2 Imports . . . . . . . . . . . . . . . 6 2.5. Translation of the MODULE-IDENTITY Macro . . . . . . . . . 7 2.6. Translation of the TEXTUAL-CONVENTION Macro . . . . . . . 7 2.7. Translation of OBJECT IDENTIFIER Assignments . . . . . . . 8 2.8. Translation of the OBJECT-TYPE Macro . . . . . . . . . . . 8 2.8.1. Translation scalars and columnar objects . . . . . . . 8 2.8.2. Translation tree nodes and non-augmenting conceptual tables . . . . . . . . . . . . . . . . . . 9 2.8.3. Translation augmenting conceptual tables . . . . . . . 10 2.9. Translation of the OBJECT-IDENTITY Macro . . . . . . . . . 10 2.10. Translation of the NOTIFICATION-TYPE Macro . . . . . . . . 10 3. YANG Extension Definition . . . . . . . . . . . . . . . . . . 12 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 5. Security Considerations . . . . . . . . . . . . . . . . . . . 15 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 16 6.1. Normative References . . . . . . . . . . . . . . . . . . . 16 6.2. Informative References . . . . . . . . . . . . . . . . . . 16 Appendix A. Example: Translation of IF-MIB . . . . . . . . . . . 17 Appendix B. Changes from 00 to 01 . . . . . . . . . . . . . . . . 24 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 25 Schoenwaelder Expires May 12, 2011 [Page 2] Internet-Draft Translation of SMIv2 to YANG November 2010 1. Introduction This document describes an translation of SMIv2 [RFC2578], [RFC2579], [RFC2580] MIB modules into YANG [RFC6020] modules. The mapping is illustrated in Appendix A by outlining the translation of the IF-MIB [RFC2863] SMIv2 module. 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]. Schoenwaelder Expires May 12, 2011 [Page 3] Internet-Draft Translation of SMIv2 to YANG November 2010 2. Translation of SMIv2 to YANG This section defines the mapping of SMIv2 constructs to YANG constructs. 2.1. Mapping of Special Types The SMIv2 base types and some well known derived textual-conventions are mapped to YANG types according to Table 1. The mapping of the OCTET STRING depends on the context. If an OCTET STRING type has an associated DISPLAY-HINT, then the corresponding YANG base type is the string type. Otherwise, the binary type is used. Similarly, the mapping of the INTEGER type depends on its usage as an enumeration or a 32-bit integral type. Mapping of SMIv2 types to YANG types +------------+----------------+-----------------+-------------------+ | SMIv2 | SMIv2 Type | YANG Module | YANG Type | | Module | | | | +------------+----------------+-----------------+-------------------+ | SNMPv2-SMI | INTEGER | | enumeration | | SNMPv2-SMI | INTEGER | | int32 | | SNMPv2-SMI | Integer32 | | int32 | | SNMPv2-SMI | OCTET STRING | | binary | | SNMPv2-SMI | OCTET STRING | | string | | SNMPv2-SMI | OBJECT | ietf-yang-types | object-identifier | | | IDENTIFIER | | | | SNMPv2-SMI | BITS | | bits | | SNMPv2-SMI | IpAddress | ietf-inet-types | ipv4-address | | SNMPv2-SMI | Counter32 | ietf-yang-types | counter32 | | SNMPv2-SMI | Gauge32 | ietf-yang-types | gauge32 | | SNMPv2-SMI | TimeTicks | ietf-yang-types | timeticks | | SNMPv2-SMI | Opaque | | binary | | SNMPv2-SMI | Counter64 | ietf-yang-types | counter64 | | SNMPv2-SMI | Unsigned32 | | uint32 | | SNMPv2-TC | PhysAddress | ietf-yang-types | phys-address | | SNMPv2-TC | MacAddress | ietf-yang-types | mac-address | | SNMPv2-TC | TimeStamp | ietf-yang-types | timestamp | +------------+----------------+-----------------+-------------------+ Table 1 Note that the mappings shown above may impact the imports of a module. Implementations must add any additional imports required by the mapping. Schoenwaelder Expires May 12, 2011 [Page 4] Internet-Draft Translation of SMIv2 to YANG November 2010 2.2. Module Prefix Generation The input to the prefix generation algorithm is a set of prefixes (usually derived from imported module names) and a specific module name to convert into a prefix. The algorithm described below produces a prefix for the given module name that is unique within the set of prefixes. Special prefixes for well known SMIv2 and YANG modules +---------------------+--------+ | YANG / SMIv2 Module | Prefix | +---------------------+--------+ | ietf-yang-types | yang | | ietf-inet-types | inet | +---------------------+--------+ Table 2 o First, some fixed translations (see Table 2) mapping well known SMIv2 and YANG modules to short prefixes are tried. If a fixed translation rule exists and leads to a conflict free prefix, then the result of the fixed translation is used. o Otherwise, prefixes are generated by tokenizing an SMIv2 module name where hyphens are treated as token separators. The tokens associated with a module name are converted to lowercase characters. The shortest sequence of token concatenated using hyphens as separators which includes at least two tokens and is unique among all prefixes used in the set of prefixes associated with module names. In the worst case, the prefix derived from an SMIv2 module name becomes the SMIv2 module name translated to lower-case. But on average, much shorter prefixes are generated. 2.3. Translation of SMIv2 Modules SMIv2 modules are mapped to corresponding YANG modules. The YANG module name is the same as the SMIv2 module name. The YANG namespace is constructed out of a constant prefix followed by the SMIv2 module name. Since SMIv2 module names are unique, the resulting YANG namespace is unique. The registered prefix is urn:ietf:params:xml:ns:yang:smiv2:, see the IANA considerations section. The YANG prefix is derived from the SMIv2 module name. Since the Schoenwaelder Expires May 12, 2011 [Page 5] Internet-Draft Translation of SMIv2 to YANG November 2010 YANG prefix is supposed to be short and must be unique within the set of all prefixes used by a YANG module, the module prefix generation algorithm described in Section 2.2 is used. 2.4. Translation of SMIv2 Imports SMIv2 IMPORT clauses are translated to YANG import statements. One major difference between the SMIv2 import mechanism and the YANG import mechanism is that SMIv2 imports specific symbols from a module while the YANG import statement imports all symbols of the referenced YANG module. SMIv2 imports that are ignored in YANG +--------------+--------------------+ | SMIv2 Module | SMIv2 Symbol | +--------------+--------------------+ | SNMPv2-SMI | MODULE-IDENTITY | | SNMPv2-SMI | OBJECT-IDENTITY | | SNMPv2-SMI | OBJECT-TYPE | | SNMPv2-SMI | NOTIFICATION-TYPE | | SNMPv2-SMI | mib-2 | | SNMPv2-TC | TEXTUAL-CONVENTION | | SNMPv2-CONF | OBJECT-GROUP | | SNMPv2-CONF | NOTIFICATION-GROUP | | SNMPv2-CONF | MODULE-COMPLIANCE | | SNMPv2-CONF | AGENT-CAPABILITIES | | SNMPv2-MIB | snmpTraps | | SNMPv2-SMI | all symbols | | SNMPv2-CONF | all symbols | +--------------+--------------------+ Table 3 In order to produce correct and complete YANG import statements, it is necessary to apply the following rules: o Ignore all imports listed in Table 3. Note that the modules SNMPv2-SMI and SNMPv2-CONF are completely ignored since all definitions in these modules are translated by translation rules. o Add any imports required by the type translations according to the type mapping table. This requires to consider all the types used in the translation unit. The argument of the generated import statements are the untranslated SMIv2 module name. The import statement must contain a prefix statement. The prefixes are generated by applying the module prefix Schoenwaelder Expires May 12, 2011 [Page 6] Internet-Draft Translation of SMIv2 to YANG November 2010 generation algorithm described in Section 2.2. 2.5. Translation of the MODULE-IDENTITY Macro The clauses of the SMIv2 MODULE-IDENTITY macro are mapped to equivalent YANG statements. o The SMIv2 ORGANIZATION clause is mapped to the YANG organization statement. o The SMIv2 CONTACT-INFO clause is mapped to the YANG contact statement. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o Each SMIv2 REVISION clause is mapped to a YANG revision statement. The revision is identified by the date of contained in the SMIv2 REVISION. DESCRIPTION sub-clauses of REVISION clauses are mapped to corresponding description statement nested in revision clauses. o The SMIv2 LAST-UPDATED is ignored if the associated date matches a REVISION clause. Otherwise, an additional revision statement is generated. o The value of the invocation of an SMIv2 MODULE-IDENTITY macro is ignored. 2.6. Translation of the TEXTUAL-CONVENTION Macro The SMIv2 uses invocations of the TEXTUAL-CONVENTION macro to define new types derived from the SMIv2 base types. Invocations of the TEXTUAL-CONVENTION macro are translated into YANG typedef statements. The name of the TEXTUAL-CONVENTION macro invocation is used as the name of the generated typedef statement. The clauses of the SMIv2 TEXTUAL-CONVENTION macro are mapped to YANG statements embedded in the typedef statement as follows: o The SMIv2 DISPLAY-HINT clause is used to determine the type mapping of types derived form the OCTET STRING type as explained in Section 2.1. Furthermore, the DISPLAY-HINT value is used to generate a regular expression for the YANG pattern statement within the type statement. [[TODO: Define a translation algorithm that is simple and produces correct and usable results for the majority of simple DISPLAY-HINTS.]] Schoenwaelder Expires May 12, 2011 [Page 7] Internet-Draft Translation of SMIv2 to YANG November 2010 o The SMIv2 STATUS clause is mapped to the YANG status statement. The generation of the YANG status statement is skipped if the value of the STATUS clause is current. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o The SMIv2 REFERENCE clause is mapped to the YANG reference statement. o The SMIv2 SYNTAX clause is mapped to the YANG type statement. SMIv2 range restrictions are mapped to YANG range statements while SMIv2 length restrictions are mapped to YANG length statements. SMIv2 INTEGER enumerations and SMIv2 BITS are mapped to YANG enum / value and bit / position statements. 2.7. Translation of OBJECT IDENTIFIER Assignments The mapping suppresses many structural OBJECT IDENTIFIER assignments that are typically used to organize the OBJECT IDENTIFIER tree. Only tree nodes that contain scalars or tables are translated to YANG containers. When generating YANG containers, the container is marked as config false. [[DISCUSS: Do we keep this flat translation? Are there corner cases where structural OIDs are used as values?]] 2.8. Translation of the OBJECT-TYPE Macro The SMIv2 uses the OBJECT-TYPE macro to define objects and the structure of conceptual tables. Objects exist either as scalars (exactly one instance within an SNMP context) or columnar objects (zero or multiple instances within an SNMP context) within conceptual tables. A subset of columnar objects of a table define the index (key) of the table. Furthermore, conceptual tables can augment other conceptual tables. All these differences must be taken into account when mapping SMIv2 OBJECT-TYPE macro invocations to YANG. 2.8.1. Translation scalars and columnar objects The SMIv2 OBJECT-TYPE macro invocations defining scalars or columnar objects are translated to YANG leaf statements. The name of the leaf is the name associated with the SMIv2 OBJECT-TYPE macro invocation. o The SMIv2 SYNTAX clause is mapped to the YANG type clause. Embedded clauses are generates as described in Section 2.1. o The SMIv2 UNITS clause is mapped to the YANG units statement. Schoenwaelder Expires May 12, 2011 [Page 8] Internet-Draft Translation of SMIv2 to YANG November 2010 o The SMIv2 MAX-ACCESS clause is ignored. o The SMIv2 STATUS clause is mapped to the YANG status statement. The generation of the YANG status statement is skipped if the value of the STATUS clause is current. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o The SMIv2 REFERENCE clause is mapped to the YANG reference statement. o The value of the SMIv2 OBJECT-TYPE macro invocation is ignored. 2.8.2. Translation tree nodes and non-augmenting conceptual tables In a first pass, iterate over the object identifier tree identifying all nodes that contain scalars and all non-augmenting conceptual tables. For each node, create a YANG container statement. For nodes representing groups of scalar objects, generate the necessary YANG leaf statements as described above. For nodes representing non- augmenting conceptual tables, identify the table entry OBJECT-TYPE, create a YANG list statement named after the SMIv2 entry OBJECT-TYPE. The rest of the clauses are translated as follows: o The SMIv2 SYNTAX clause is ignored. o The SMIv2 UNITS clause is ignored. o The SMIv2 MAX-ACCESS clause is ignored. o The SMIv2 STATUS clause is mapped to the YANG status statement. The generation of the YANG status statement is skipped if the value of the STATUS clause is current. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o The SMIv2 REFERENCE clause is mapped to the YANG reference statement. o The SMIv2 INDEX clause is mapped to the YANG key clause listing the columnar objects forming the key of the YANG list. o The value of the SMIv2 OBJECT-TYPE macro invocation is ignored. Note that the SMIv2 non-augmenting conceptual table node is not translated to YANG. Within the list statement, create YANG leaf Schoenwaelder Expires May 12, 2011 [Page 9] Internet-Draft Translation of SMIv2 to YANG November 2010 nodes as described above. For objects listed in the SMIv2 INDEX clause that are not part of the conceptual table itself, create YANG leaf statements of type leafref pointing to the referenced definition. 2.8.3. Translation augmenting conceptual tables In a second pass, iterate over all augmenting conceptual tables. For each augmenting conceptual table, identify the table entry OBJECT- TYPE, create a YANG augment statement with the first argument containing the path of the augmented table. The rest of the clauses are translated as follows: o The SMIv2 SYNTAX clause is ignored. o The SMIv2 UNITS clause is ignored. o The SMIv2 MAX-ACCESS clause is ignored. o The SMIv2 STATUS clause is mapped to the YANG status statement. The generation of the YANG status statement is skipped if the value of the STATUS clause is current. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o The SMIv2 REFERENCE clause is mapped to the YANG reference statement. o The value of the SMIv2 OBJECT-TYPE macro invocation is ignored. Note that the SMIv2 augmenting conceptual table node is not translated to YANG. Within the augment statement, create YANG leaf nodes as described above. 2.9. Translation of the OBJECT-IDENTITY Macro [[TODO]] 2.10. Translation of the NOTIFICATION-TYPE Macro The SMIv2 provides the NOTIFICATION-TYPE macro to define notifications. YANG provides the notification statement for the same purpose. The name of the NOTIFICATION-TYPE macro invocation is used as the name of the generated notification statement. The clauses of the NOTIFICATION-TYPE macro are mapped to YANG statements embedded in the notification statement as follows. Schoenwaelder Expires May 12, 2011 [Page 10] Internet-Draft Translation of SMIv2 to YANG November 2010 o The SMIv2 OBJECTS clause is mapped to a sequence of YANG containers. For each object listed in the OBJECTS clause value, a YANG container statement is generated. The name of this container is the name of the notification and the name of the current concatenated by a hyphen. If the current object belongs a conceptual table, then a sequence of leaf statements is generated for each INDEX of the SMIv2 conceptual table. Next, a leaf statement is generated for the current object. All container leafs are marked as config false. o The SMIv2 STATUS clause is mapped to the YANG status statement. The generation of the YANG status statement is skipped if the value of the STATUS clause is current. o The SMIv2 DESCRIPTION clause is mapped to the YANG description statement. o The SMIv2 REFERENCE clause is mapped to the YANG reference statement. o The value of the SMIv2 NOTIFICATION-TYPE macro invocation is ignored. Schoenwaelder Expires May 12, 2011 [Page 11] Internet-Draft Translation of SMIv2 to YANG November 2010 3. YANG Extension Definition This section defines some YANG extension statements that can be used to carry additional information from the original SMIv2 module into the YANG module. The YANG module references [RFC2578] and [RFC2579]. file "ietf-yang-smiv2@2010-11-08.yang" module ietf-yang-smiv2 { namespace "urn:ietf:params:xml:ns:yang:ietf-yang-smiv2"; prefix "smiv2"; organization "IETF NETMOD (NETCONF Data Modeling Language) Working Group"; contact "WG Web: WG List: WG Chair: David Kessens WG Chair: Juergen Schoenwaelder Editor: Juergen Schoenwaelder "; description "This module defines YANG extensions that are used to translate SMIv2 concepts into YANG. Copyright (c) 2010 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 (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; // RFC Ed.: replace XXXX with actual RFC number and remove this note // RFC Ed.: please update the date to the date of publication Schoenwaelder Expires May 12, 2011 [Page 12] Internet-Draft Translation of SMIv2 to YANG November 2010 revision 2010-09-24 { description "Initial revision."; reference "RFC XXXX: Translation of SMIv2 MIB Modules to YANG Modules"; // RFC Ed.: replace XXXX with actual RFC number and remove this note } extension oid { argument "value"; description "The oid statement takes as an argument the object identifier assigned to an SMIv2 definition. The object identifier value is written in decimal dotted notation."; reference "RFC2578: Structure of Management Information Version 2 (SMIv2)"; } extension display-hint { argument "format"; description "The display-hint statement takes as an argument the DISPLAY-HINT assigned to an SMIv2 textual convention."; reference "RFC2579: Textual Conventions for SMIv2"; } extension max-access { argument "access"; description "The max-access statement takes as an argument the MAX-ACCESS assigned to an SMIv2 object definition"; reference "RFC2578: Structure of Management Information Version 2 (SMIv2)"; } extension defval { argument "value"; description "The defval statement takes as an argument a default value defined by an SMIv2 DEFVAL clause."; "RFC2578: Structure of Management Information Version 2 (SMIv2)"; } } Schoenwaelder Expires May 12, 2011 [Page 13] Internet-Draft Translation of SMIv2 to YANG November 2010 4. IANA Considerations This document registers two URIs in the IETF XML registry [RFC3688]. Following the format in RFC 3688, the following registrations have been made. URI: urn:ietf:params:xml:ns:yang:ietf-yang-smiv2 Registrant Contact: The NETMOD WG of the IETF. XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:smiv2 Registrant Contact: The NETMOD WG of the IETF. XML: N/A, the requested URI is an XML namespace. This document registers a YANG module in the YANG Module Names registry [RFC6020]. name: ietf-yang-smiv2 namespace: urn:ietf:params:xml:ns:yang:ietf-yang-smiv2 prefix: smiv2 reference: RFC XXXX Schoenwaelder Expires May 12, 2011 [Page 14] Internet-Draft Translation of SMIv2 to YANG November 2010 5. Security Considerations TBD Schoenwaelder Expires May 12, 2011 [Page 15] Internet-Draft Translation of SMIv2 to YANG November 2010 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [RFC2579] McCloghrie, K., Ed., Perkins, D., Ed., and J. Schoenwaelder, Ed., "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. 6.2. Informative References [RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group MIB", RFC 2863, June 2000. [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. Schoenwaelder Expires May 12, 2011 [Page 16] Internet-Draft Translation of SMIv2 to YANG November 2010 Appendix A. Example: Translation of IF-MIB The translation of the IF-MIB [RFC2863] leads to the following YANG module frame. The prefix is the translation of the SMIv2 module name IF-MIB to lowercase (consisting of two token and thus no abbreviation). module IF-MIB { namespace "urn:ietf:params:xml:ns:yang:smiv2:IF-MIB"; prefix "if-mib"; } The translation of the IMPORTs of the IF-MIB leads to the following YANG import statements: import IANAifType-MIB { prefix "ianaiftype-mib"; } import SNMPv2-TC { prefix "smiv2-tc"; } import ietf-yang-types { prefix "yang"; } import ietf-yang-smiv2 { prefix "smiv2"; } The translation of the IF-MIB MODULE-IDENTITY macro invocation leads to the following YANG statements: Schoenwaelder Expires May 12, 2011 [Page 17] Internet-Draft Translation of SMIv2 to YANG November 2010 organization "IETF Interfaces MIB Working Group"; contact "Keith McCloghrie Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 US 408-526-5260 kzm@cisco.com"; description "The MIB module to describe generic objects for network interface sub-layers. This MIB is an updated version of MIB-II's ifTable, and incorporates the extensions defined in RFC 1229."; revision "2000-06-14" { description "Clarifications agreed upon by the Interfaces MIB WG, and published as RFC 2863."; } revision "1996-02-28" { description "Revisions made by the Interfaces MIB WG, and published in RFC 2233."; } revision "1993-11-08" { description "Initial revision, published as part of RFC 1573."; } The translation of the OwnerString and InterfaceIndex textual- conventions of the IF-MIB are shown below. Schoenwaelder Expires May 12, 2011 [Page 18] Internet-Draft Translation of SMIv2 to YANG November 2010 typedef OwnerString { type string { length "0..255"; pattern "\p{IsBasicLatin}{0,255}"; } status deprecated; description "This data type is used to model an administratively assigned name of the owner of a resource. This information is taken from the NVT ASCII character set. It is suggested that this name contain one or more of the following: ASCII form of the manager station's transport address, management station name (e.g., domain name), network management personnel's name, location, or phone number. In some cases the agent itself will be the owner of an entry. In these cases, this string shall be set to a string starting with 'agent'."; } typedef InterfaceIndex { type int32 { range "1..2147483647"; } description "A unique value, greater than zero, for each interface or interface sub-layer in the managed system. It is recommended that values are assigned contiguously starting from 1. The value for each interface sub-layer must remain constant at least from one re-initialization of the entity's network management system to the next re-initialization."; } The translation of the some key parts of the IF-MIB are shown below. container interfaces { config false; leaf ifNumber { type int32; description "The number of network interfaces (regardless of their current state) present on this system."; } list ifEntry { key "ifIndex"; description "An entry containing management information applicable to a Schoenwaelder Expires May 12, 2011 [Page 19] Internet-Draft Translation of SMIv2 to YANG November 2010 particular interface."; leaf ifIndex { type if-mib:InterfaceIndex; description "A unique value, greater than zero, for each interface. It is recommended that values are assigned contiguously starting from 1. The value for each interface sub-layer must remain constant at least from one re-initialization of the entity's network management system to the next re- initialization."; } leaf ifDescr { type smiv2-tc:DisplayString { length "0..255"; } description "A textual string containing information about the interface. This string should include the name of the manufacturer, the product name and the version of the interface hardware/software."; } /* skipping several definitions */ leaf ifAdminStatus { type enumeration { enum up { value 1; } enum down { value 2; } enum testing { value 3; } } description "The desired state of the interface. The testing(3) state indicates that no operational packets can be passed. When a managed system initializes, all interfaces start with ifAdminStatus in the down(2) state. As a result of either explicit management action or per configuration information retained by the managed system, ifAdminStatus is then changed to either the up(1) or testing(3) states (or remains in the down(2) state)."; } /* skipping more definitions */ } } Schoenwaelder Expires May 12, 2011 [Page 20] Internet-Draft Translation of SMIv2 to YANG November 2010 augment "/if-mib:interfaces/if-mib:ifEntry" { description "An entry containing additional management information applicable to a particular interface."; leaf ifName { type smiv2-tc:DisplayString; description "The textual name of the interface. The value of this object should be the name of the interface as assigned by the local device and should be suitable for use in commands entered at the device's `console'. This might be a text name, such as `le0' or a simple port number, such as `1', depending on the interface naming syntax of the device. If several entries in the ifTable together represent a single interface as named by the device, then each will have the same value of ifName. Note that for an agent which responds to SNMP queries concerning an interface on some other (proxied) device, then the value of ifName for such an interface is the proxied device's local name for it. If there is no local name, or this object is otherwise not applicable, then this object contains a zero-length string."; } /* skipping more definitions */ } The translation of the linkDown notification of the IF-MIB is shown below. notification linkDown { description "A linkDown trap signifies that the SNMP entity, acting in an agent role, has detected that the ifOperStatus object for one of its communication links is about to enter the down state from some other state (but not from the notPresent state). This other state is indicated by the included value of ifOperStatus."; container linkDown-ifIndex { config false; leaf ifIndex { type leafref { path "/if-mib:interfaces/if-mib:ifEntry/if-mib:ifIndex"; } description "[Automagically generated leafref leaf.]"; Schoenwaelder Expires May 12, 2011 [Page 21] Internet-Draft Translation of SMIv2 to YANG November 2010 } } container linkDown-ifAdminStatus { config false; leaf ifIndex { type leafref { path "/if-mib:interfaces/if-mib:ifEntry/if-mib:ifIndex"; } description "[Automagically generated leafref leaf.]"; } leaf ifAdminStatus { type enumeration { enum up { value 1; } enum down { value 2; } enum testing { value 3; } } description "The desired state of the interface. The testing(3) state indicates that no operational packets can be passed. When a managed system initializes, all interfaces start with ifAdminStatus in the down(2) state. As a result of either explicit management action or per configuration information retained by the managed system, ifAdminStatus is then changed to either the up(1) or testing(3) states (or remains in the down(2) state)."; } } container linkDown-ifOperStatus { config false; leaf ifIndex { type leafref { path "/if-mib:interfaces/if-mib:ifEntry/if-mib:ifIndex"; } description "[Automagically generated leafref leaf.]"; } leaf ifOperStatus { type enumeration { enum up { value 1; } enum down { value 2; } enum testing { value 3; } enum unknown { value 4; } enum dormant { value 5; } enum notPresent { value 6; } enum lowerLayerDown { value 7; } Schoenwaelder Expires May 12, 2011 [Page 22] Internet-Draft Translation of SMIv2 to YANG November 2010 } description "The current operational state of the interface. The testing(3) state indicates that no operational packets can be passed. If ifAdminStatus is down(2) then ifOperStatus should be down(2). If ifAdminStatus is changed to up(1) then ifOperStatus should change to up(1) if the interface is ready to transmit and receive network traffic; it should change to dormant(5) if the interface is waiting for external actions (such as a serial line waiting for an incoming connection); it should remain in the down(2) state if and only if there is a fault that prevents it from going to the up(1) state; it should remain in the notPresent(6) state if the interface has missing (typically, hardware) components."; } } } Schoenwaelder Expires May 12, 2011 [Page 23] Internet-Draft Translation of SMIv2 to YANG November 2010 Appendix B. Changes from 00 to 01 o Translation is config false; top-level container are marked as config false. o Revised the overall document structure, added a YANG module for the definition of YANG extensions (smiv2:oid, smiv2:display-hint, smiv2:max-access, smiv2:defval), moved the IF-MIB example into an appendix. o Alignment with RFC 6020 and RFC 6021. o Started to use [[DISCUSS]] and [[TODO]] markers inside the text instead of maintaining a TODO list as an appendix. Schoenwaelder Expires May 12, 2011 [Page 24] Internet-Draft Translation of SMIv2 to YANG November 2010 Author's Address Juergen Schoenwaelder (editor) Jacobs University Email: j.schoenwaelder@jacobs-university.de Schoenwaelder Expires May 12, 2011 [Page 25]