Network Working Group                                         R. Austein
Request for Comments: 1611               Epilogue Technology Corporation
Category: Standards Track                                     J. Saperia
                                           Digital Equipment Corporation
                                                                May 1994

                       DNS Server MIB Extensions

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Table of Contents

   1. Introduction ..............................................    1
   2. The SNMPv2 Network Management Framework ...................    2
   2.1 Object Definitions .......................................    2
   3. Overview ..................................................    2
   3.1 Resolvers ................................................    3
   3.2 Name Servers .............................................    3
   3.3 Selected Objects .........................................    4
   3.4 Textual Conventions ......................................    4
   4. Definitions ...............................................    5
   5. Acknowledgements ..........................................   28
   6. References ................................................   28
   7. Security Considerations ...................................   29
   8. Authors' Addresses ........................................   30

1.  Introduction

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes a set of extensions which instrument DNS
   name server functions.  This memo was produced by the DNS working
   group.

   With the adoption of the Internet-standard Network Management
   Framework [4,5,6,7], and with a large number of vendor
   implementations of these standards in commercially available
   products, it became possible to provide a higher level of effective
   network management in TCP/IP-based internets than was previously
   available.  With the growth in the use of these standards, it has
   become possible to consider the management of other elements of the
   infrastructure beyond the basic TCP/IP protocols.  A key element of

   the TCP/IP infrastructure is the DNS.

   Up to this point there has been no mechanism to integrate the
   management of the DNS with SNMP-based managers.  This memo provides
   the mechanisms by which IP-based management stations can effectively
   manage DNS name server software in an integrated fashion.

   We have defined DNS MIB objects to be used in conjunction with the
   Internet MIB to allow access to and control of DNS name server
   software via SNMP by the Internet community.

2.  The SNMPv2 Network Management Framework

   The SNMPv2 Network Management Framework consists of four major
   components.  They are:

      o  RFC 1442 which defines the SMI, the mechanisms used for
         describing and naming objects for the purpose of management.

      o  STD 17, RFC 1213 defines MIB-II, the core set of managed objects
         for the Internet suite of protocols.

      o  RFC 1445 which defines the administrative and other architectural
         aspects of the framework.

      o  RFC 1448 which defines the protocol used for network access to
         managed objects.

      The Framework permits new objects to be defined for the purpose of
      experimentation and evaluation.

2.1.  Object Definitions

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Objects in the MIB are
   defined using the subset of Abstract Syntax Notation One (ASN.1)
   defined in the SMI.  In particular, each object object type is named
   by an OBJECT IDENTIFIER, an administratively assigned name.  The
   object type together with an object instance serves to uniquely
   identify a specific instantiation of the object.  For human
   convenience, we often use a textual string, termed the descriptor, to
   refer to the object type.

3.  Overview

   In theory, the DNS world is pretty simple.  There are two kinds of
   entities: resolvers and name servers.  Resolvers ask questions.  Name
   servers answer them.  The real world, however, is not so simple.

   Implementors have made widely differing choices about how to divide
   DNS functions between resolvers and servers.  They have also
   constructed various sorts of exotic hybrids.  The most difficult task
   in defining this MIB was to accommodate this wide range of entities
   without having to come up with a separate MIB for each.

   We divided up the various DNS functions into two, non-overlapping
   classes, called "resolver functions" and "name server functions."  A
   DNS entity that performs what we define as resolver functions
   contains a resolver, and therefore must implement the MIB groups
   required of all resolvers which are defined in a separate MIB Module.
   A DNS entity which implements name server functions is considered to
   be a name server, and must implement the MIB groups required for name
   servers in this module.  If the same piece of software performs both
   resolver and server functions, we imagine that it contains both a
   resolver and a server and would thus implement both the DNS Server
   and DNS Resolver MIBs.

3.1.  Resolvers

   In our model, a resolver is a program (or piece thereof) which
   obtains resource records from servers.  Normally it does so at the
   behest of an application, but may also do so as part of its own
   operation.  A resolver sends DNS protocol queries and receives DNS
   protocol replies.  A resolver neither receives queries nor sends
   replies.  A full service resolver is one that knows how to resolve
   queries: it obtains the needed resource records by contacting a
   server authoritative for the records desired.  A stub resolver does
   not know how to resolve queries: it sends all queries to a local name
   server, setting the "recursion desired" flag to indicate that it
   hopes that the name server will be willing to resolve the query.  A
   resolver may (optionally) have a cache for remembering previously
   acquired resource records.  It may also have a negative cache for
   remembering names or data that have been determined not to exist.

3.2.  Name Servers

   A name server is a program (or piece thereof) that provides resource
   records to resolvers.  All references in this document to "a name
   server" imply "the name server's role"; in some cases the name
   server's role and the resolver's role might be combined into a single
   program.  A name server receives DNS protocol queries and sends DNS
   protocol replies.  A name server neither sends queries nor receives
   replies.  As a consequence, name servers do not have caches.
   Normally, a name server would expect to receive only those queries to
   which it could respond with authoritative information.  However, if a
   name server receives a query that it cannot respond to with purely
   authoritative information, it may choose to try to obtain the

   necessary additional information from a resolver which may or may not
   be a separate process.

3.3.  Selected Objects

   Many of the objects included in this memo have been created from
   information contained in the DNS specifications [1,2], as amended and
   clarified by subsequent host requirements documents [3].  Other
   objects have been created based on experience with existing DNS
   management tools, expected operational needs, the statistics
   generated by existing DNS implementations, and the configuration
   files used by existing DNS implementations.  These objects have been
   ordered into groups as follows:

      o  Server Configuration Group

      o  Server Counter Group

      o  Server Optional Counter Group

      o  Server Zone Group

   This information has been converted into a standard form using the
   SNMPv2 SMI defined in [9].  For the most part, the descriptions are
   influenced by the DNS related RFCs noted above.  For example, the
   descriptions for counters used for the various types of queries of
   DNS records are influenced by the definitions used for the various
   record types found in [2].

3.4.  Textual Conventions

   Several conceptual data types have been introduced as a textual
   conventions in this DNS MIB document.  These additions will
   facilitate the common understanding of information used by the DNS.
   No changes to the SMI or the SNMP are necessary to support these
   conventions.

   Readers familiar with MIBs designed to manage entities in the lower
   layers of the Internet protocol suite may be surprised at the number
   of non-enumerated integers used in this MIB to represent values such
   as DNS RR class and type numbers.  The reason for this choice is
   simple: the DNS itself is designed as an extensible protocol,
   allowing new classes and types of resource records to be added to the
   protocol without recoding the core DNS software.  Using non-
   enumerated integers to represent these data types in this MIB allows
   the MIB to accommodate these changes as well.

4.  Definitions

   DNS-SERVER-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       mib-2
           FROM RFC-1213
       MODULE-IDENTITY, OBJECT-TYPE, OBJECT-IDENTITY,
       IpAddress, Counter32, Gauge32
           FROM SNMPv2-SMI
       TEXTUAL-CONVENTION, RowStatus, DisplayString, TruthValue
           FROM SNMPv2-TC
       MODULE-COMPLIANCE, OBJECT-GROUP
           FROM SNMPv2-CONF;

   dns OBJECT-IDENTITY
       STATUS  current
       DESCRIPTION
               "The OID assigned to DNS MIB work by the IANA."
       ::= { mib-2 32 }

   dnsServMIB MODULE-IDENTITY
       LAST-UPDATED "9401282251Z"
       ORGANIZATION "IETF DNS Working Group"
       CONTACT-INFO
               "       Rob Austein
               Postal: Epilogue Technology Corporation
                       268 Main Street, Suite 283
                       North Reading, MA 10864
                       US
                  Tel: +1 617 245 0804
                  Fax: +1 617 245 8122
               E-Mail: sra@epilogue.com

                       Jon Saperia
               Postal: Digital Equipment Corporation
                       110 Spit Brook Road
                       ZKO1-3/H18
                       Nashua, NH 03062-2698
                       US
                  Tel: +1 603 881 0480
                  Fax: +1 603 881 0120
                Email: saperia@zko.dec.com"
       DESCRIPTION
               "The MIB module for entities implementing the server side
               of the Domain Name System (DNS) protocol."
       ::= { dns 1 }

   dnsServMIBObjects       OBJECT IDENTIFIER ::= { dnsServMIB 1 }

   -- (Old-style) groups in the DNS server MIB.

   dnsServConfig           OBJECT IDENTIFIER ::= { dnsServMIBObjects 1 }
   dnsServCounter          OBJECT IDENTIFIER ::= { dnsServMIBObjects 2 }
   dnsServOptCounter       OBJECT IDENTIFIER ::= { dnsServMIBObjects 3 }
   dnsServZone             OBJECT IDENTIFIER ::= { dnsServMIBObjects 4 }


   -- Textual conventions

   DnsName ::= TEXTUAL-CONVENTION
       -- A DISPLAY-HINT would be nice, but difficult to express.
       STATUS  current
       DESCRIPTION
               "A DNS name is a sequence of labels.  When DNS names are
               displayed, the boundaries between labels are typically
               indicated by dots (e.g. `Acme' and `COM' are labels in
               the name `Acme.COM').  In the DNS protocol, however, no
               such separators are needed because each label is encoded
               as a length octet followed by the indicated number of
               octets of label.  For example, `Acme.COM' is encoded as
               the octet sequence { 4, 'A', 'c', 'm', 'e', 3, 'C', 'O',
               'M', 0 } (the final 0 is the length of the name of the
               root domain, which appears implicitly at the end of any
               DNS name).  This MIB uses the same encoding as the DNS
               protocol.

               A DnsName must always be a fully qualified name.  It is
               an error to encode a relative domain name as a DnsName
               without first making it a fully qualified name."
       REFERENCE
               "RFC-1034 section 3.1."
       SYNTAX  OCTET STRING (SIZE (0..255))

   DnsNameAsIndex ::= TEXTUAL-CONVENTION
       STATUS  current
       DESCRIPTION
               "This textual convention is like a DnsName, but is used
               as an index componant in tables.  Alphabetic characters
               in names of this type are restricted to uppercase: the
               characters 'a' through 'z' are mapped to the characters
               'A' through 'Z'.  This restriction is intended to make
               the lexical ordering imposed by SNMP useful when applied
               to DNS names.

               Note that it is theoretically possible for a valid DNS

               name to exceed the allowed length of an SNMP object
               identifer, and thus be impossible to represent in tables
               in this MIB that are indexed by DNS name.  Sampling of
               DNS names in current use on the Internet suggests that
               this limit does not pose a serious problem in practice."
       REFERENCE
               "RFC-1034 section 3.1, RFC-1448 section 4.1."
       SYNTAX  DnsName

   DnsClass ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "2d"
       STATUS  current
       DESCRIPTION
               "This data type is used to represent the class values
               which appear in Resource Records in the DNS.  A 16-bit
               unsigned integer is used to allow room for new classes
               of records to be defined.  Existing standard classes are
               listed in the DNS specifications."
       REFERENCE
               "RFC-1035 section 3.2.4."
       SYNTAX  INTEGER (0..65535)

   DnsType ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "2d"
       STATUS  current
       DESCRIPTION
               "This data type is used to represent the type values
               which appear in Resource Records in the DNS.  A 16-bit
               unsigned integer is used to allow room for new record
               types to be defined.  Existing standard types are listed
               in the DNS specifications."
       REFERENCE
               "RFC-1035 section 3.2.2."
       SYNTAX  INTEGER (0..65535)

   DnsQClass ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "2d"
       STATUS  current
       DESCRIPTION
               "This data type is used to represent the QClass values
               which appear in Resource Records in the DNS.  A 16-bit
               unsigned integer is used to allow room for new QClass
               records to be defined.  Existing standard QClasses are
               listed in the DNS specification."
       REFERENCE
               "RFC-1035 section 3.2.5."
       SYNTAX  INTEGER (0..65535)

   DnsQType ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "2d"
       STATUS  current
       DESCRIPTION
               "This data type is used to represent the QType values
               which appear in Resource Records in the DNS.  A 16-bit
               unsigned integer is used to allow room for new QType
               records to be defined.  Existing standard QTypes are
               listed in the DNS specification."
       REFERENCE
               "RFC-1035 section 3.2.3."
       SYNTAX  INTEGER (0..65535)

   DnsTime ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "4d"
       STATUS  current
       DESCRIPTION
               "DnsTime values are 32-bit unsigned integers which
               measure time in seconds."
       REFERENCE
               "RFC-1035."
       SYNTAX  Gauge32


   DnsOpCode ::= TEXTUAL-CONVENTION
       STATUS  current
       DESCRIPTION
               "This textual convention is used to represent the DNS
               OPCODE values used in the header section of DNS
               messages.  Existing standard OPCODE values are listed in
               the DNS specifications."
       REFERENCE
               "RFC-1035 section 4.1.1."
       SYNTAX  INTEGER (0..15)

   DnsRespCode ::= TEXTUAL-CONVENTION
       STATUS  current
       DESCRIPTION
               "This data type is used to represent the DNS RCODE value
               in DNS response messages.  Existing standard RCODE
               values are listed in the DNS specifications."
       REFERENCE
               "RFC-1035 section 4.1.1."
       SYNTAX  INTEGER (0..15)

   -- Server Configuration Group

   dnsServConfigImplementIdent OBJECT-TYPE
       SYNTAX      DisplayString
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "The implementation identification string for the DNS
               server software in use on the system, for example;
               `FNS-2.1'"
       ::= { dnsServConfig 1 }

   dnsServConfigRecurs  OBJECT-TYPE
       SYNTAX      INTEGER { available(1),
                             restricted(2),
                             unavailable(3) }
       MAX-ACCESS  read-write
       STATUS      current
       DESCRIPTION
               "This represents the recursion services offered by this
               name server.  The values that can be read or written
               are:

               available(1) - performs recursion on requests from
               clients.

               restricted(2) - recursion is performed on requests only
               from certain clients, for example; clients on an access
               control list.

               unavailable(3) - recursion is not available."
        ::= { dnsServConfig 2 }

   dnsServConfigUpTime OBJECT-TYPE
       SYNTAX      DnsTime
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "If the server has a persistent state (e.g., a process),
               this value will be the time elapsed since it started.
               For software without persistant state, this value will
               be zero."
       ::= { dnsServConfig 3 }

   dnsServConfigResetTime OBJECT-TYPE
       SYNTAX      DnsTime
       MAX-ACCESS  read-only
       STATUS      current

       DESCRIPTION
               "If the server has a persistent state (e.g., a process)
               and supports a `reset' operation (e.g., can be told to
               re-read configuration files), this value will be the
               time elapsed since the last time the name server was
               `reset.'  For software that does not have persistence or
               does not support a `reset' operation, this value will be
               zero."
       ::= { dnsServConfig 4 }

   dnsServConfigReset OBJECT-TYPE
       SYNTAX      INTEGER { other(1),
                             reset(2),
                             initializing(3),
                             running(4) }
       MAX-ACCESS  read-write
       STATUS      current
       DESCRIPTION
               "Status/action object to reinitialize any persistant name
               server state.  When set to reset(2), any persistant
               name server state (such as a process) is reinitialized as
               if the name server had just been started.  This value
               will never be returned by a read operation.  When read,
               one of the following values will be returned:
                   other(1) - server in some unknown state;
                   initializing(3) - server (re)initializing;
                   running(4) - server currently running."
       ::= { dnsServConfig 5 }


   -- Server Counter Group

   dnsServCounterAuthAns OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries which were authoritatively answered."
       ::= { dnsServCounter 2 }

   dnsServCounterAuthNoNames OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries for which `authoritative no such name'
               responses were made."
       ::= { dnsServCounter 3 }

   dnsServCounterAuthNoDataResps OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries for which `authoritative no such data'
               (empty answer) responses were made."
       ::= { dnsServCounter 4 }

   dnsServCounterNonAuthDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries which were non-authoritatively
               answered (cached data)."
       ::= { dnsServCounter 5 }

   dnsServCounterNonAuthNoDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries which were non-authoritatively
               answered with no data (empty answer)."
       ::= { dnsServCounter 6 }

   dnsServCounterReferrals OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests that were referred to other servers."
       ::= { dnsServCounter 7 }

   dnsServCounterErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed that were
               answered with errors (RCODE values other than 0 and 3)."
       REFERENCE
               "RFC-1035 section 4.1.1."
       ::= { dnsServCounter 8 }

   dnsServCounterRelNames OBJECT-TYPE
       SYNTAX      Counter32

       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received by the server for names that
               are only 1 label long (text form - no internal dots)."
       ::= { dnsServCounter 9 }

   dnsServCounterReqRefusals OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of DNS requests refused by the server."
       ::= { dnsServCounter 10 }

   dnsServCounterReqUnparses OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received which were unparseable."
       ::= { dnsServCounter 11 }

   dnsServCounterOtherErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests which were aborted for other (local)
               server errors."
       ::= { dnsServCounter 12 }

   -- DNS Server Counter Table

   dnsServCounterTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF DnsServCounterEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "Counter information broken down by DNS class and type."
       ::= { dnsServCounter 13 }

   dnsServCounterEntry OBJECT-TYPE
       SYNTAX      DnsServCounterEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "This table contains count information for each DNS class

               and type value known to the server.  The index allows
               management software to to create indices to the table to
               get the specific information desired, e.g., number of
               queries over UDP for records with type value `A' which
               came to this server.  In order to prevent an
               uncontrolled expansion of rows in the table; if
               dnsServCounterRequests is 0 and dnsServCounterResponses
               is 0, then the row does not exist and `no such' is
               returned when the agent is queried for such instances."
       INDEX     { dnsServCounterOpCode,
                   dnsServCounterQClass,
                   dnsServCounterQType,
                   dnsServCounterTransport }
       ::= { dnsServCounterTable 1 }

   DnsServCounterEntry ::=
       SEQUENCE {
           dnsServCounterOpCode
               DnsOpCode,
           dnsServCounterQClass
               DnsClass,
           dnsServCounterQType
               DnsType,
           dnsServCounterTransport
               INTEGER,
           dnsServCounterRequests
               Counter32,
           dnsServCounterResponses
               Counter32
           }

   dnsServCounterOpCode OBJECT-TYPE
       SYNTAX      DnsOpCode
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "The DNS OPCODE being counted in this row of the table."
       ::= { dnsServCounterEntry 1 }

   dnsServCounterQClass OBJECT-TYPE
       SYNTAX      DnsClass
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "The class of record being counted in this row of the
               table."
       ::= { dnsServCounterEntry 2 }

   dnsServCounterQType OBJECT-TYPE
       SYNTAX      DnsType
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "The type of record which is being counted in this row in
               the table."
       ::= { dnsServCounterEntry 3 }

   dnsServCounterTransport OBJECT-TYPE
       SYNTAX      INTEGER { udp(1), tcp(2), other(3) }
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "A value of udp(1) indicates that the queries reported on
               this row were sent using UDP.

               A value of tcp(2) indicates that the queries reported on
               this row were sent using TCP.

               A value of other(3) indicates that the queries reported
               on this row were sent using a transport that was neither
               TCP nor UDP."
       ::= { dnsServCounterEntry 4 }

   dnsServCounterRequests OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests (queries) that have been recorded in
               this row of the table."
       ::= { dnsServCounterEntry 5 }

   dnsServCounterResponses OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of responses made by the server since
               initialization for the kind of query identified on this
               row of the table."
       ::= { dnsServCounterEntry 6 }

   -- Server Optional Counter Group

   -- The Server Optional Counter Group is intended for those systems
   -- which make distinctions between the different sources of the DNS
   -- queries as defined below.
   --
   -- Objects in this group are implemented on servers which distinguish
   -- between queries which originate from the same host as the server,
   -- queries from one of an arbitrary group of hosts that are on an
   -- access list defined by the server, and queries from hosts that do
   -- not fit either of these descriptions.
   --
   -- The objects found in the Server Counter group are totals.  Thus if
   -- one wanted to identify, for example, the number of queries from
   -- `remote' hosts which have been given authoritative answers, one
   -- would subtract the current values of ServOptCounterFriendsAuthAns
   -- and ServOptCounterSelfAuthAns from servCounterAuthAns.
   --
   -- The purpose of these distinctions is to allow for implementations
   -- to group queries and responses on this basis.  One way in which
   -- servers may make these distinctions is by looking at the source IP
   -- address of the DNS query.  If the source of the query is `your
   -- own' then the query should be counted as `yourself' (local host).
   -- If the source of the query matches an `access list,' the query
   -- came from a friend.  What constitutes an `access list' is
   -- implementation dependent and could be as simple as a rule that all
   -- hosts on the same IP network as the DNS server are classed
   -- `friends.'
   --
   -- In order to avoid double counting, the following rules apply:
   --
   -- 1. No host is in more than one of the three groups defined above.
   --
   -- 2. All queries from the local host are always counted in the
   --    `yourself' group regardless of what the access list, if any,
   --    says.
   --
   -- 3. The access list should not define `your friends' in such a way
   --    that it includes all hosts.   That is, not everybody is your
   --    `friend.'

   dnsServOptCounterSelfAuthAns OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host for which

               there has been an authoritative answer."
       ::= { dnsServOptCounter 1 }

   dnsServOptCounterSelfAuthNoNames OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host for which
               there has been an authoritative no such name answer
               given."
       ::= { dnsServOptCounter 2 }

   dnsServOptCounterSelfAuthNoDataResps OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host for which
               there has been an authoritative no such data answer
               (empty answer) made."
       ::= { dnsServOptCounter 3 }

   dnsServOptCounterSelfNonAuthDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host for which a
               non-authoritative answer (cached data) was made."
       ::= { dnsServOptCounter 4 }

   dnsServOptCounterSelfNonAuthNoDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host for which a
               `non-authoritative, no such data' response was made
               (empty answer)."
       ::= { dnsServOptCounter 5 }

   dnsServOptCounterSelfReferrals OBJECT-TYPE
       SYNTAX      Counter32

       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries the server has processed which
               originated from a resolver on the same host and were
               referred to other servers."
       ::= { dnsServOptCounter 6 }

   dnsServOptCounterSelfErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from a resolver on the same host which have
               been answered with errors (RCODEs other than 0 and 3)."
       REFERENCE
               "RFC-1035 section 4.1.1."
       ::= { dnsServOptCounter 7 }

   dnsServOptCounterSelfRelNames OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received for names that are only 1
               label long (text form - no internal dots) the server has
               processed which originated from a resolver on the same
               host."
       ::= { dnsServOptCounter 8 }

   dnsServOptCounterSelfReqRefusals OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of DNS requests refused by the server which
               originated from a resolver on the same host."
       ::= { dnsServOptCounter 9 }

   dnsServOptCounterSelfReqUnparses OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received which were unparseable and
               which originated from a resolver on the same host."
       ::= { dnsServOptCounter 10 }

   dnsServOptCounterSelfOtherErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests which were aborted for other (local)
               server errors and which originated on the same host."
       ::= { dnsServOptCounter 11 }

   dnsServOptCounterFriendsAuthAns OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries originating from friends which were
               authoritatively answered.  The definition of friends is
               a locally defined matter."
       ::= { dnsServOptCounter 12 }

   dnsServOptCounterFriendsAuthNoNames OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries originating from friends, for which
               authoritative `no such name' responses were made.  The
               definition of friends is a locally defined matter."
       ::= { dnsServOptCounter 13 }

   dnsServOptCounterFriendsAuthNoDataResps OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries originating from friends for which
               authoritative no such data (empty answer) responses were
               made.  The definition of friends is a locally defined
               matter."
       ::= { dnsServOptCounter 14 }

   dnsServOptCounterFriendsNonAuthDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries originating from friends which were
               non-authoritatively answered (cached data). The
               definition of friends is a locally defined matter."

       ::= { dnsServOptCounter 15 }

   dnsServOptCounterFriendsNonAuthNoDatas OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of queries originating from friends which were
               non-authoritatively answered with no such data (empty
               answer)."
       ::= { dnsServOptCounter 16 }

   dnsServOptCounterFriendsReferrals OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests which originated from friends that
               were referred to other servers.  The definition of
               friends is a locally defined matter."
       ::= { dnsServOptCounter 17 }

   dnsServOptCounterFriendsErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests the server has processed which
               originated from friends and were answered with errors
               (RCODE values other than 0 and 3).  The definition of
               friends is a locally defined matter."
       REFERENCE
               "RFC-1035 section 4.1.1."
       ::= { dnsServOptCounter 18 }

   dnsServOptCounterFriendsRelNames OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received for names from friends that
               are only 1 label long (text form - no internal dots) the
               server has processed."
       ::= { dnsServOptCounter 19 }

   dnsServOptCounterFriendsReqRefusals OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only

       STATUS      current
       DESCRIPTION
               "Number of DNS requests refused by the server which were
               received from `friends'."
       ::= { dnsServOptCounter 20 }

   dnsServOptCounterFriendsReqUnparses OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests received which were unparseable and
               which originated from `friends'."
       ::= { dnsServOptCounter 21 }

   dnsServOptCounterFriendsOtherErrors OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Number of requests which were aborted for other (local)
               server errors and which originated from `friends'."
       ::= { dnsServOptCounter 22 }


   -- Server Zone Group

   -- DNS Management Zone Configuration Table

   -- This table contains zone configuration information.

   dnsServZoneTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF DnsServZoneEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "Table of zones for which this name server provides
               information.  Each of the zones may be loaded from stable
               storage via an implementation-specific mechanism or may
               be obtained from another name server via a zone transfer.

               If name server doesn't load any zones, this table is
               empty."
       ::= { dnsServZone 1 }

   dnsServZoneEntry OBJECT-TYPE
       SYNTAX      DnsServZoneEntry
       MAX-ACCESS  not-accessible

       STATUS      current
       DESCRIPTION
               "An entry in the name server zone table.  New rows may be
               added either via SNMP or by the name server itself."
       INDEX     { dnsServZoneName,
                   dnsServZoneClass }
       ::= { dnsServZoneTable 1 }

   DnsServZoneEntry ::=
       SEQUENCE {
           dnsServZoneName
               DnsNameAsIndex,
           dnsServZoneClass
               DnsClass,
           dnsServZoneLastReloadSuccess
               DnsTime,
           dnsServZoneLastReloadAttempt
               DnsTime,
           dnsServZoneLastSourceAttempt
               IpAddress,
           dnsServZoneStatus
               RowStatus,
           dnsServZoneSerial
               Counter32,
           dnsServZoneCurrent
               TruthValue,
           dnsServZoneLastSourceSuccess
               IpAddress
       }

   dnsServZoneName OBJECT-TYPE
       SYNTAX      DnsNameAsIndex
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "DNS name of the zone described by this row of the table.
               This is the owner name of the SOA RR that defines the
               top of the zone. This is name is in uppercase:
               characters 'a' through 'z' are mapped to 'A' through 'Z'
               in order to make the lexical ordering useful."
       ::= { dnsServZoneEntry 1 }

   dnsServZoneClass OBJECT-TYPE
       SYNTAX      DnsClass
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "DNS class of the RRs in this zone."

       ::= { dnsServZoneEntry 2 }

   dnsServZoneLastReloadSuccess OBJECT-TYPE
       SYNTAX      DnsTime
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Elapsed time in seconds since last successful reload of
               this zone."
       ::= { dnsServZoneEntry 3 }

   dnsServZoneLastReloadAttempt OBJECT-TYPE
       SYNTAX      DnsTime
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Elapsed time in seconds since last attempted reload of
               this zone."
       ::= { dnsServZoneEntry 4 }

   dnsServZoneLastSourceAttempt OBJECT-TYPE
       SYNTAX      IpAddress
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "IP address of host from which most recent zone transfer
               of this zone was attempted.  This value should match the
               value of dnsServZoneSourceSuccess if the attempt was
               succcessful.  If zone transfer has not been attempted
               within the memory of this name server, this value should
               be 0.0.0.0."
       ::= { dnsServZoneEntry 5 }

   dnsServZoneStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
               "The status of the information represented in this row of
               the table."
       ::= { dnsServZoneEntry 6 }

   dnsServZoneSerial OBJECT-TYPE
       SYNTAX      Counter32
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Zone serial number (from the SOA RR) of the zone

               represented by this row of the table.  If the zone has
               not been successfully loaded within the memory of this
               name server, the value of this variable is zero."
       ::= { dnsServZoneEntry 7 }

   dnsServZoneCurrent OBJECT-TYPE
       SYNTAX      TruthValue
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "Whether the server's copy of the zone represented by
               this row of the table is currently valid.  If the zone
               has never been successfully loaded or has expired since
               it was last succesfully loaded, this variable will have
               the value false(2), otherwise this variable will have
               the value true(1)."
       ::= { dnsServZoneEntry 8 }

   dnsServZoneLastSourceSuccess OBJECT-TYPE
       SYNTAX      IpAddress
       MAX-ACCESS  read-only
       STATUS      current
       DESCRIPTION
               "IP address of host which was the source of the most
               recent successful zone transfer for this zone.  If
               unknown (e.g., zone has never been successfully
               transfered) or irrelevant (e.g., zone was loaded from
               stable storage), this value should be 0.0.0.0."
       ::= { dnsServZoneEntry 9 }

   -- DNS Zone Source Table

   dnsServZoneSrcTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF DnsServZoneSrcEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "This table is a list of IP addresses from which the
               server will attempt to load zone information using DNS
               zone transfer operations.  A reload may occur due to SNMP
               operations that create a row in dnsServZoneTable or a
               SET to object dnsServZoneReload.  This table is only
               used when the zone is loaded via zone transfer."
       ::= { dnsServZone 2 }

   dnsServZoneSrcEntry OBJECT-TYPE
       SYNTAX      DnsServZoneSrcEntry
       MAX-ACCESS  not-accessible

       STATUS      current
       DESCRIPTION
               "An entry in the name server zone source table."
       INDEX     { dnsServZoneSrcName,
                   dnsServZoneSrcClass,
                   dnsServZoneSrcAddr }
       ::= { dnsServZoneSrcTable 1 }

   DnsServZoneSrcEntry ::=
       SEQUENCE {
           dnsServZoneSrcName
               DnsNameAsIndex,
           dnsServZoneSrcClass
               DnsClass,
           dnsServZoneSrcAddr
               IpAddress,
           dnsServZoneSrcStatus
               RowStatus
       }

   dnsServZoneSrcName OBJECT-TYPE
       SYNTAX      DnsNameAsIndex
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "DNS name of the zone to which this entry applies."
       ::= { dnsServZoneSrcEntry 1 }

   dnsServZoneSrcClass OBJECT-TYPE
       SYNTAX      DnsClass
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "DNS class of zone to which this entry applies."
       ::= { dnsServZoneSrcEntry 2 }

   dnsServZoneSrcAddr OBJECT-TYPE
       SYNTAX      IpAddress
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
               "IP address of name server host from which this zone
               might be obtainable."
       ::= { dnsServZoneSrcEntry 3 }

   dnsServZoneSrcStatus OBJECT-TYPE
       SYNTAX      RowStatus
       MAX-ACCESS  read-create

       STATUS      current
       DESCRIPTION
               "The status of the information represented in this row of
               the table."
       ::= { dnsServZoneSrcEntry 4 }


   -- SNMPv2 groups.

   dnsServMIBGroups        OBJECT IDENTIFIER ::= { dnsServMIB 2 }

   dnsServConfigGroup OBJECT-GROUP
       OBJECTS   { dnsServConfigImplementIdent,
                   dnsServConfigRecurs,
                   dnsServConfigUpTime,
                   dnsServConfigResetTime,
                   dnsServConfigReset }
       STATUS      current
       DESCRIPTION
               "A collection of objects providing basic configuration
               control of a DNS name server."
       ::= { dnsServMIBGroups 1 }

   dnsServCounterGroup OBJECT-GROUP
       OBJECTS   { dnsServCounterAuthAns,
                   dnsServCounterAuthNoNames,
                   dnsServCounterAuthNoDataResps,
                   dnsServCounterNonAuthDatas,
                   dnsServCounterNonAuthNoDatas,
                   dnsServCounterReferrals,
                   dnsServCounterErrors,
                   dnsServCounterRelNames,
                   dnsServCounterReqRefusals,
                   dnsServCounterReqUnparses,
                   dnsServCounterOtherErrors,
                   dnsServCounterOpCode,
                   dnsServCounterQClass,
                   dnsServCounterQType,
                   dnsServCounterTransport,
                   dnsServCounterRequests,
                   dnsServCounterResponses }
       STATUS      current
       DESCRIPTION
               "A collection of objects providing basic instrumentation
               of a DNS name server."
       ::= { dnsServMIBGroups 2 }

   dnsServOptCounterGroup OBJECT-GROUP
       OBJECTS   { dnsServOptCounterSelfAuthAns,
                   dnsServOptCounterSelfAuthNoNames,
                   dnsServOptCounterSelfAuthNoDataResps,
                   dnsServOptCounterSelfNonAuthDatas,
                   dnsServOptCounterSelfNonAuthNoDatas,
                   dnsServOptCounterSelfReferrals,
                   dnsServOptCounterSelfErrors,
                   dnsServOptCounterSelfRelNames,
                   dnsServOptCounterSelfReqRefusals,
                   dnsServOptCounterSelfReqUnparses,
                   dnsServOptCounterSelfOtherErrors,
                   dnsServOptCounterFriendsAuthAns,
                   dnsServOptCounterFriendsAuthNoNames,
                   dnsServOptCounterFriendsAuthNoDataResps,
                   dnsServOptCounterFriendsNonAuthDatas,
                   dnsServOptCounterFriendsNonAuthNoDatas,
                   dnsServOptCounterFriendsReferrals,
                   dnsServOptCounterFriendsErrors,
                   dnsServOptCounterFriendsRelNames,
                   dnsServOptCounterFriendsReqRefusals,
                   dnsServOptCounterFriendsReqUnparses,
                   dnsServOptCounterFriendsOtherErrors }
       STATUS      current
       DESCRIPTION
               "A collection of objects providing extended
               instrumentation of a DNS name server."
       ::= { dnsServMIBGroups 3 }

   dnsServZoneGroup OBJECT-GROUP
       OBJECTS   { dnsServZoneName,
                   dnsServZoneClass,
                   dnsServZoneLastReloadSuccess,
                   dnsServZoneLastReloadAttempt,
                   dnsServZoneLastSourceAttempt,
                   dnsServZoneLastSourceSuccess,
                   dnsServZoneStatus,
                   dnsServZoneSerial,
                   dnsServZoneCurrent,
                   dnsServZoneSrcName,
                   dnsServZoneSrcClass,
                   dnsServZoneSrcAddr,
                   dnsServZoneSrcStatus }
       STATUS      current
       DESCRIPTION
               "A collection of objects providing configuration control
               of a DNS name server which loads authoritative zones."
       ::= { dnsServMIBGroups 4 }

   -- Compliances.

   dnsServMIBCompliances OBJECT IDENTIFIER ::= { dnsServMIB 3 }

   dnsServMIBCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
               "The compliance statement for agents implementing the DNS
               name server MIB extensions."
       MODULE -- This MIB module
           MANDATORY-GROUPS { dnsServConfigGroup, dnsServCounterGroup }
           GROUP   dnsServOptCounterGroup
           DESCRIPTION
               "The server optional counter group is unconditionally
               optional."
           GROUP   dnsServZoneGroup
           DESCRIPTION
               "The server zone group is mandatory for any name server
               that acts as an authoritative server for any DNS zone."
           OBJECT  dnsServConfigRecurs
           MIN-ACCESS      read-only
           DESCRIPTION
               "This object need not be writable."
           OBJECT  dnsServConfigReset
           MIN-ACCESS      read-only
           DESCRIPTION
               "This object need not be writable."
       ::= { dnsServMIBCompliances 1 }

   END

5.  Acknowledgements

   This document is the result of work undertaken the by DNS working
   group.  The authors would particularly like to thank the following
   people for their contributions to this document: Philip Almquist,
   Frank Kastenholz (FTP Software), Joe Peck (DEC), Dave Perkins
   (SynOptics), Win Treese (DEC), and Mimi Zohar (IBM).

6.  References

   [1] Mockapetris, P., "Domain Names -- Concepts and Facilities", STD
       13, RFC 1034, USC/Information Sciences Institute, November 1987.

   [2] Mockapetris, P., "Domain Names -- Implementation and
       Specification", STD 13, RFC 1035, USC/Information Sciences
       Institute, November 1987.

   [3] Braden, R., Editor, "Requirements for Internet Hosts --
       Application and Support, STD 3, RFC 1123, USC/Information
       Sciences Institute, October 1989.

   [4] Rose, M., and K. McCloghrie, "Structure and Identification of
       Management Information for TCP/IP-based internets", STD 16, RFC
       1155, Performance Systems International, Hughes LAN Systems, May
       1990.

   [5] McCloghrie, K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based internets", RFC 1156, Hughes
       LAN Systems, Performance Systems International, May 1990.

   [6] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple
       Network Management Protocol", STD 15, RFC 1157, SNMP Research,
       Performance Systems International, Performance Systems
       International, MIT Laboratory for Computer Science, May 1990.

   [7] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
       STD 16, RFC 1212, Performance Systems International, Hughes LAN
       Systems, March 1991.

   [8] McCloghrie, K., and M. Rose, Editors, "Management Information
       Base for Network Management of TCP/IP-based internets: MIB-II",
       STD 17, RFC 1213, Hughes LAN Systems, Performance Systems
       International, March 1991.

   [9] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Structure
       of Management Information for version 2 of the Simple Network
       Management Protocol (SNMPv2)", RFC 1442, SNMP Research, Inc.,
       Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon

       University, April 1993.

  [10] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Textual
       Conventions for version 2 of the the Simple Network Management
       Protocol (SNMPv2)", RFC 1443, SNMP Research, Inc., Hughes LAN
       Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

  [11] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
       "Conformance Statements for version 2 of the the Simple Network
       Management Protocol (SNMPv2)", RFC 1444, SNMP Research, Inc.,
       Hughes LAN Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

  [12] Galvin, J., and K. McCloghrie, "Administrative Model for version
       2 of the Simple Network Management Protocol (SNMPv2)", RFC 1445,
       Trusted Information Systems, Hughes LAN Systems, April 1993.

  [13] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
       Operations for version 2 of the Simple Network Management
       Protocol (SNMPv2)", RFC 1448, SNMP Research, Inc., Hughes LAN
       Systems, Dover Beach Consulting, Inc., Carnegie Mellon
       University, April 1993.

  [14] "Information processing systems - Open Systems Interconnection -
       Specification of Abstract Syntax Notation One (ASN.1)",
       International Organization for Standardization, International
       Standard 8824, December 1987.

7.  Security Considerations

   Security issues are not discussed in this memo.

8.  Authors' Addresses

   Rob Austein
   Epilogue Technology Corporation
   268 Main Street, Suite 283
   North Reading, MA 01864
   USA

   Phone: +1-617-245-0804
   Fax:   +1-617-245-8122
   EMail: sra@epilogue.com


   Jon Saperia
   Digital Equipment Corporation
   110 Spit Brook Road
   ZKO1-3/H18
   Nashua, NH 03062-2698
   USA

   Phone: +1-603-881-0480
   Fax:   +1-603-881-0120
   EMail: saperia@zko.dec.com