Network Working Group N. Freed

Network Working Group N. Freed
Request for Comments: 2789 Innosoft
Obsoletes: 2249, 1566 S. Kille
Category: Standards Track MessagingDirect Ltd.
March 2000

Mail Monitoring MIB

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.

Copyright Notice

Copyright (C) The Internet Society (2000). All Rights Reserved.

Introduction

This memo defines a portion of the Management Information Base (MIB)
for use with network management protocols in the Internet community.
Specifically, this memo extends the basic Network Services Monitoring
MIB defined in RFC 2788 [16] to allow monitoring of Message Transfer
Agents (MTAs). It may also be used to monitor MTA components within
gateways.

Table of Contents

1 The SNMP Network Management Framework ....................... 2
2 Message Flow Model .......................................... 3
3 MTA Objects ................................................. 3
4 Definitions ................................................. 4
5 Changes made since RFC 2249 ................................. 29
6 Acknowledgements ............................................ 30
7 References .................................................. 30
8 Security Considerations ..................................... 31
9 Author and Chair Addresses .................................. 32
10 Full Copyright Statement .................................... 33

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RFC 2789 Mail Monitoring MIB March 2000

1. The SNMP Network Management Framework

The SNMP Management Framework presently consists of five major
components:

o An overall architecture, described in RFC 2571 [1].

o Mechanisms for describing and naming objects and events for the
purpose of management. The first version of this Structure of
Management Information (SMI) is called SMIv1 and described in STD
16, RFC 1155 [2], STD 16, RFC 1212 [3] and RFC 1215 [4]. The
second version, called SMIv2, is described in STD 58, RFC 2578
[5], STD 58, RFC 2579 [6] and STD 58, RFC 2580 [7].

o Message protocols for transferring management information. The
first version of the SNMP message protocol is called SNMPv1 and
described in STD 15, RFC 1157 [8]. A second version of the SNMP
message protocol, which is not an Internet standards track
protocol, is called SNMPv2c and described in RFC 1901 [9] and RFC
1906 [10]. The third version of the message protocol is called
SNMPv3 and described in RFC 1906 [10], RFC 2572 [11] and RFC 2574
[12].

o Protocol operations for accessing management information. The
first set of protocol operations and associated PDU formats is
described in STD 15, RFC 1157 [8]. A second set of protocol
operations and associated PDU formats is described in RFC 1905
[13].

o A set of fundamental applications described in RFC 2573 [14] and
the view-based access control mechanism described in RFC 2575
[15].

Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the mechanisms defined in the SMI.

This memo specifies a MIB module that is compliant to the SMIv2. A
MIB conforming to the SMIv1 can be produced through the appropriate
translations. The resulting translated MIB must be semantically
equivalent, except where objects or events are omitted because no
translation is possible (use of Counter64). Some machine readable
information in SMIv2 will be converted into textual descriptions in
SMIv1 during the translation process. However, this loss of machine
readable information is not considered to change the semantics of the
MIB.

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2. Message Flow Model

A general model of message flow inside an MTA has to be presented
before a MIB can be described. Generally speaking, message flow is
modelled as occurring in four steps:

(1) Messages are received by the MTA from User Agents, Message
Stores, other MTAs, and gateways.

(2) The "next hop" for the each message is determined. This is simply
the destination the message is to be transmitted to; it may or
may not be the final destination of the message. Multiple "next
hops" may exist for a single message (as a result of either
having multiple recipients or distribution list expansion); this
may make it necessary to duplicate messages.

(3) If necessary messages are converted into the format that's
appropriate for the next hop. Conversion operations may be
successful or unsuccessful.

(4) Messages are transmitted to the appropriate destination, which
may be a User Agent, Message Store, another MTA, or gateway.

Storage of messages in the MTA occurs at some point during this
process. However, it is important to note that storage may occur at
different and possibly even multiple points during this process. For
example, some MTAs expand messages into multiple copies as they are
received. In this case (1), (2), and (3) may all occur prior to
storage. Other MTAs store messages precisely as they are received and
perform all expansions and conversions during retransmission
processing. So here only (1) occurs prior to storage. This leads to
situations where, in general, a measurement of messages received may
not equal a measurement of messages in store, or a measurement of
messages stored may not equal a measurement of messages
retransmitted, or both.

3. MTA Objects

If there are one or more MTAs on the host, the following MIB may be
used to monitor them. Any number of the MTAs on a single host or
group of hosts may be monitored. Each MTA is dealt with as a separate
network service and has its own applTable entry in the Network
Services Monitoring MIB.

The MIB described in this document covers only the portion which is
specific to the monitoring of MTAs. The network service related part
of the MIB is covered in RFC 2788 [16].

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This MIB defines four tables. The first of these contains per-MTA
information that isn't specific to any particular part of MTA. The
second breaks each MTA down into a collection of separate components
called groups. Groups are described in detail in the comments
embedded in the MIB below. The third table provides a means of
correlating associations tracked by the network services MIB with
specific groups within different MTAs. Finally, the fourth table
provides a means of tracking any errors encountered during the
operation of the MTA. The first two tables must be implemented to
conform with this MIB; the last two are optional.

4. Definitions

MTA-MIB DEFINITIONS ::= BEGIN

IMPORTS
OBJECT-TYPE, Counter32, Gauge32, MODULE-IDENTITY, mib-2
FROM SNMPv2-SMI
TimeInterval
FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP
FROM SNMPv2-CONF
SnmpAdminString
FROM SNMP-FRAMEWORK-MIB
applIndex, URLString
FROM NETWORK-SERVICES-MIB;

mta MODULE-IDENTITY
LAST-UPDATED "200003030000Z"
ORGANIZATION "IETF Mail and Directory Management Working Group"
CONTACT-INFO
" Ned Freed

Postal: Innosoft International, Inc.
1050 Lakes Drive
West Covina, CA 91790
US

Tel: +1 626 919 3600
Fax: +1 626 919 3614

E-Mail: [email protected]"
DESCRIPTION
"The MIB module describing Message Transfer Agents (MTAs)"
REVISION "200003030000Z"
DESCRIPTION
"This revision, published in RFC 2789, changes a number of
DisplayStrings to SnmpAdminStrings. Note that this change

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RFC 2789 Mail Monitoring MIB March 2000

is not strictly supported by SMIv2. However, the alternative
of deprecating the old objects and defining new objects
would have a more adverse impact on backward compatibility
and interoperability, given the particular semantics of
these objects. The defining reference for distinguished
names has also been updated from RFC 1779 to RFC 2253."
REVISION "199905120000Z"
DESCRIPTION
"This revision fixes a number of technical problems found in
previous versions: The conformance groups for different
versions of this MIB have been corrected, the recommendation
that an empty string be returned if the last operation was
successful has been removed from
mtaGroupInboundRejectionReason and
mtaGroupOutboundConnectFailureReason as it conflicts
with the stated purpose of these variables, and the
required mtaStatusCode entry has been added to
MtaGroupErrorEntry. It should be noted that this last
change in no way affects the bits on the wire."
REVISION "199708170000Z"
DESCRIPTION
"This revision, published in RFC 2249, adds the
mtaGroupDescription and mtaGroupURL fields, conversion
operation counters, a group hierarchy description mechanism,
counters for specific errors, oldest message IDs, per-MTA
and per-group loop counters, and a new table for tracking
any errors an MTA encounters."
REVISION "199311280000Z"
DESCRIPTION
"The original version of this MIB was published in RFC 1566"
::= {mib-2 28}

mtaTable OBJECT-TYPE
SYNTAX SEQUENCE OF MtaEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding information specific to an MTA."
::= {mta 1}

mtaEntry OBJECT-TYPE
SYNTAX MtaEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The entry associated with each MTA."
INDEX {applIndex}
::= {mtaTable 1}

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MtaEntry ::= SEQUENCE {
mtaReceivedMessages
Counter32,
mtaStoredMessages
Gauge32,
mtaTransmittedMessages
Counter32,
mtaReceivedVolume
Counter32,
mtaStoredVolume
Gauge32,
mtaTransmittedVolume
Counter32,
mtaReceivedRecipients
Counter32,
mtaStoredRecipients
Gauge32,
mtaTransmittedRecipients
Counter32,
mtaSuccessfulConvertedMessages
Counter32,
mtaFailedConvertedMessages
Counter32,
mtaLoopsDetected
Counter32
}

mtaReceivedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages received since MTA initialization.
This includes messages transmitted to this MTA from other
MTAs as well as messages that have been submitted to the
MTA directly by end-users or applications."
::= {mtaEntry 1}

mtaStoredMessages OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of messages currently stored in the MTA.
This includes messages that are awaiting transmission to
some other MTA or are waiting for delivery to an end-user
or application."
::= {mtaEntry 2}

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mtaTransmittedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages transmitted since MTA initialization.
This includes messages that were transmitted to some other
MTA or are waiting for delivery to an end-user or
application."
::= {mtaEntry 3}

mtaReceivedVolume OBJECT-TYPE
SYNTAX Counter32
UNITS "K-octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total volume of messages received since MTA
initialization, measured in kilo-octets. This volume should
include all transferred data that is logically above the mail
transport protocol level. For example, an SMTP-based MTA
should use the number of kilo-octets in the message header
and body, while an X.400-based MTA should use the number of
kilo-octets of P2 data. This includes messages transmitted
to this MTA from other MTAs as well as messages that have
been submitted to the MTA directly by end-users or
applications."
::= {mtaEntry 4}

mtaStoredVolume OBJECT-TYPE
SYNTAX Gauge32
UNITS "K-octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total volume of messages currently stored in the MTA,
measured in kilo-octets. This volume should include all
stored data that is logically above the mail transport
protocol level. For example, an SMTP-based MTA should
use the number of kilo-octets in the message header and
body, while an X.400-based MTA would use the number of
kilo-octets of P2 data. This includes messages that are
awaiting transmission to some other MTA or are waiting
for delivery to an end-user or application."
::= {mtaEntry 5}

mtaTransmittedVolume OBJECT-TYPE
SYNTAX Counter32

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UNITS "K-octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total volume of messages transmitted since MTA
initialization, measured in kilo-octets. This volume should
include all transferred data that is logically above the mail
transport protocol level. For example, an SMTP-based MTA
should use the number of kilo-octets in the message header
and body, while an X.400-based MTA should use the number of
kilo-octets of P2 data. This includes messages that were
transmitted to some other MTA or are waiting for delivery
to an end-user or application."
::= {mtaEntry 6}

mtaReceivedRecipients OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
received since MTA initialization. Recipients this MTA
has no responsibility for, i.e. inactive envelope
recipients or ones referred to in message headers,
should not be counted even if information about such
recipients is available. This includes messages
transmitted to this MTA from other MTAs as well as
messages that have been submitted to the MTA directly
by end-users or applications."
::= {mtaEntry 7}

mtaStoredRecipients OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
currently stored in the MTA. Recipients this MTA has no
responsibility for, i.e. inactive envelope recipients or
ones referred to in message headers, should not be
counted. This includes messages that are awaiting
transmission to some other MTA or are waiting for
delivery to an end-user or application."
::= {mtaEntry 8}

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

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STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
transmitted since MTA initialization. Recipients this
MTA had no responsibility for, i.e. inactive envelope
recipients or ones referred to in message headers,
should not be counted. This includes messages that were
transmitted to some other MTA or are waiting for
delivery to an end-user or application."
::= {mtaEntry 9}

mtaSuccessfulConvertedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages that have been successfully
converted from one form to another since MTA
initialization."
::= {mtaEntry 10}

mtaFailedConvertedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages for which an unsuccessful
attempt was made to convert them from one form to
another since MTA initialization."
::= {mtaEntry 11}

mtaLoopsDetected OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A message loop is defined as a situation where the MTA
decides that a given message will never be delivered to
one or more recipients and instead will continue to
loop endlessly through one or more MTAs. This variable
counts the number of times the MTA has detected such a
situation since MTA initialization. Note that the
mechanism MTAs use to detect loops (e.g., trace field
counting, count of references to this MTA in a trace
field, examination of DNS or other directory information,
etc.), the level at which loops are detected (e.g., per
message, per recipient, per directory entry, etc.), and
the handling of a loop once it is detected (e.g., looping

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RFC 2789 Mail Monitoring MIB March 2000

messages are held, looping messages are bounced or sent
to the postmaster, messages that the MTA knows will loop
won't be accepted, etc.) vary widely from one MTA to the
next and cannot be inferred from this variable."
::= {mtaEntry 12}

-- MTAs typically group inbound reception, queue storage, and
-- outbound transmission in some way, rather than accounting for
-- such operations only across the MTA as a whole. In the most
-- extreme case separate information will be maintained for each
-- different entity that receives messages and for each entity
-- the MTA stores messages for and delivers messages to. Other
-- MTAs may elect to treat all reception equally, all queue
-- storage equally, all deliveries equally, or some combination
-- of this. Overlapped groupings are also possible, where an MTA
-- decomposes its traffic in different ways for different
-- purposes.

-- In any case, a grouping abstraction is an extremely useful for
-- breaking down the activities of an MTA. For purposes of
-- labelling this will be called a "group" in this MIB.

-- Each group contains all the variables needed to monitor all
-- aspects of an MTA's operation. However, the fact that all
-- groups contain all possible variables does not imply that all
-- groups must use all possible variables. For example, a single
-- group might be used to monitor only one kind of event (inbound
-- processing, outbound processing, or storage). In this sort of
-- configuration any counters that are unused as a result of a
-- given MTA's use of the group construct must be inaccessible;
-- e.g., returning either a noSuchName error (for an SNMPv1 get),
-- or a noSuchInstance exception (for an SNMPv2 get).

-- Groups can be created at any time after MTA initialization. Once
-- a group is created it should not be deleted or its mtaGroupIndex
-- changed unless the MTA is reinitialized.

-- Groups are not necessarily mutually exclusive. A given event may
-- be recorded by more than one group, a message may be seen as
-- stored by more than one group, and so on. Groups should be all
-- inclusive, however: if groups are implemented all aspects of an
-- MTA's operation should be registered in at least one group.
-- This freedom lets implementors use different sets of groups to
-- provide different "views" of an MTA.

-- The possibility of overlap between groups means that summing
-- variables across groups may not produce values equal to those in
-- the mtaTable. mtaTable should always provide accurate information

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-- about the MTA as a whole.

-- The term "channel" is often used in MTA implementations; channels
-- are usually, but not always, equivalent to a group. However,
-- this MIB does not use the term "channel" because there is no
-- requirement that an MTA supporting this MIB has to map its
-- "channel" abstraction one-to-one onto the MIB's group abstraction.

-- An MTA may create a group or group of groups at any time. Once
-- created, however, an MTA cannot delete an entry for a group from
-- the group table. Deletion is only allowed when the MTA is
-- reinitialized, and is not required even then. This restriction
-- is imposed so that monitoring agents can rely on group
-- assignments being consistent across multiple query operations.

-- Groups may be laid out so as to form a hierarchical arrangement,
-- with some groups acting as subgroups for other groups.
-- Alternately, disjoint groups of groups may be used to provide
-- different sorts of "snapshots" of MTA operation. The
-- mtaGroupHierarchy variable provides an indication of how each
-- group fits into the overall arrangement being used.

-- Note that SNMP also defines and uses term "group". MTA groups are
-- NOT the same as SNMP groups.

mtaGroupTable OBJECT-TYPE
SYNTAX SEQUENCE OF MtaGroupEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding information specific to each MTA group."
::= {mta 2}

mtaGroupEntry OBJECT-TYPE
SYNTAX MtaGroupEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The entry associated with each MTA group."
INDEX {applIndex, mtaGroupIndex}
::= {mtaGroupTable 1}

MtaGroupEntry ::= SEQUENCE {
mtaGroupIndex
INTEGER,
mtaGroupReceivedMessages
Counter32,
mtaGroupRejectedMessages

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Counter32,
mtaGroupStoredMessages
Gauge32,
mtaGroupTransmittedMessages
Counter32,
mtaGroupReceivedVolume
Counter32,
mtaGroupStoredVolume
Gauge32,
mtaGroupTransmittedVolume
Counter32,
mtaGroupReceivedRecipients
Counter32,
mtaGroupStoredRecipients
Gauge32,
mtaGroupTransmittedRecipients
Counter32,
mtaGroupOldestMessageStored
TimeInterval,
mtaGroupInboundAssociations
Gauge32,
mtaGroupOutboundAssociations
Gauge32,
mtaGroupAccumulatedInboundAssociations
Counter32,
mtaGroupAccumulatedOutboundAssociations
Counter32,
mtaGroupLastInboundActivity
TimeInterval,
mtaGroupLastOutboundActivity
TimeInterval,
mtaGroupLastOutboundAssociationAttempt
TimeInterval,
mtaGroupRejectedInboundAssociations
Counter32,
mtaGroupFailedOutboundAssociations
Counter32,
mtaGroupInboundRejectionReason
SnmpAdminString,
mtaGroupOutboundConnectFailureReason
SnmpAdminString,
mtaGroupScheduledRetry
TimeInterval,
mtaGroupMailProtocol
OBJECT IDENTIFIER,
mtaGroupName
SnmpAdminString,
mtaGroupSuccessfulConvertedMessages

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Counter32,
mtaGroupFailedConvertedMessages
Counter32,
mtaGroupDescription
SnmpAdminString,
mtaGroupURL
URLString,
mtaGroupCreationTime
TimeInterval,
mtaGroupHierarchy
INTEGER,
mtaGroupOldestMessageId
SnmpAdminString,
mtaGroupLoopsDetected
Counter32
}

mtaGroupIndex OBJECT-TYPE
SYNTAX INTEGER (1..2147483647)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The index associated with a group for a given MTA."
::= {mtaGroupEntry 1}

mtaGroupReceivedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages received to this group since
group creation."
::= {mtaGroupEntry 2}

mtaGroupRejectedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages rejected by this group since
group creation."
::= {mtaGroupEntry 3}

mtaGroupStoredMessages OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION

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"The total number of messages currently stored in this
group's queue."
::= {mtaGroupEntry 4}

mtaGroupTransmittedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages transmitted by this group since
group creation."
::= {mtaGroupEntry 5}

mtaGroupReceivedVolume OBJECT-TYPE
SYNTAX Counter32
UNITS "K-octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total volume of messages received to this group since
group creation, measured in kilo-octets. This volume
should include all transferred data that is logically above
the mail transport protocol level. For example, an
SMTP-based MTA should use the number of kilo-octets in the
message header and body, while an X.400-based MTA should use
the number of kilo-octets of P2 data."
::= {mtaGroupEntry 6}

mtaGroupStoredVolume OBJECT-TYPE
SYNTAX Gauge32
UNITS "K-octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total volume of messages currently stored in this
group's queue, measured in kilo-octets. This volume should
include all stored data that is logically above the mail
transport protocol level. For example, an SMTP-based
MTA should use the number of kilo-octets in the message
header and body, while an X.400-based MTA would use the
number of kilo-octets of P2 data."
::= {mtaGroupEntry 7}

mtaGroupTransmittedVolume OBJECT-TYPE
SYNTAX Counter32
UNITS "K-octets"
MAX-ACCESS read-only
STATUS current

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DESCRIPTION
"The total volume of messages transmitted by this group
since group creation, measured in kilo-octets. This
volume should include all transferred data that is logically
above the mail transport protocol level. For example, an
SMTP-based MTA should use the number of kilo-octets in the
message header and body, while an X.400-based MTA should use
the number of kilo-octets of P2 data."
::= {mtaGroupEntry 8}

mtaGroupReceivedRecipients OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
received to this group since group creation.
Recipients this MTA has no responsibility for should not
be counted."
::= {mtaGroupEntry 9}

mtaGroupStoredRecipients OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
currently stored in this group's queue. Recipients this
MTA has no responsibility for should not be counted."
::= {mtaGroupEntry 10}

mtaGroupTransmittedRecipients OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of recipients specified in all messages
transmitted by this group since group creation.
Recipients this MTA had no responsibility for should not
be counted."
::= {mtaGroupEntry 11}

mtaGroupOldestMessageStored OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time since the oldest message in this group's queue was

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placed in the queue."
::= {mtaGroupEntry 12}

mtaGroupInboundAssociations OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of current associations to the group, where the
group is the responder."
::= {mtaGroupEntry 13}

mtaGroupOutboundAssociations OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of current associations to the group, where the
group is the initiator."
::= {mtaGroupEntry 14}

mtaGroupAccumulatedInboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of associations to the group since
group creation, where the MTA was the responder."
::= {mtaGroupEntry 15}

mtaGroupAccumulatedOutboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of associations from the group since
group creation, where the MTA was the initiator."
::= {mtaGroupEntry 16}

mtaGroupLastInboundActivity OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time since the last time that this group had an active
inbound association for purposes of message reception."
::= {mtaGroupEntry 17}

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mtaGroupLastOutboundActivity OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time since the last time that this group had a
successful outbound association for purposes of
message delivery."
::= {mtaGroupEntry 18}

mtaGroupLastOutboundAssociationAttempt OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time since the last time that this group attempted
to make an outbound association for purposes of
message delivery."
::= {mtaGroupEntry 34}

mtaGroupRejectedInboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of inbound associations the group has
rejected, since group creation. Rejected associations
are not counted in the accumulated association totals."
::= {mtaGroupEntry 19}

mtaGroupFailedOutboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number associations where the group was the
initiator and association establishment has failed,
since group creation. Failed associations are
not counted in the accumulated association totals."
::= {mtaGroupEntry 20}

mtaGroupInboundRejectionReason OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The failure reason, if any, for the last association this
group refused to respond to. If no association attempt

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has been made since the MTA was initialized the value
should be 'never'."
::= {mtaGroupEntry 21}

mtaGroupOutboundConnectFailureReason OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The failure reason, if any, for the last association attempt
this group initiated. If no association attempt has been
made since the MTA was initialized the value should be
'never'."
::= {mtaGroupEntry 22}

mtaGroupScheduledRetry OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The amount of time until this group is next scheduled to
attempt to make an association."
::= {mtaGroupEntry 23}

mtaGroupMailProtocol OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An identification of the protocol being used by this group.
For an group employing OSI protocols, this will be the
Application Context. For Internet applications, OID
values of the form {applTCPProtoID port} or {applUDPProtoID
port} are used for TCP-based and UDP-based protocols,
respectively. In either case 'port' corresponds to the
primary port number being used by the protocol. The
usual IANA procedures may be used to register ports for
new protocols. applTCPProtoID and applUDPProtoID are
defined in the NETWORK-SERVICES-MIB, RFC 2788."
::= {mtaGroupEntry 24}

mtaGroupName OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A descriptive name for the group. If this group connects to
a single remote MTA this should be the name of that MTA. If

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RFC 2789 Mail Monitoring MIB March 2000

this in turn is an Internet MTA this should be the domain
name. For an OSI MTA it should be the string encoded
distinguished name of the managed object using the format
defined in RFC 2253. For X.400(1984) MTAs which do not
have a Distinguished Name, the RFC 2156 syntax
'mta in globalid' used in X400-Received: fields can be
used."
::= {mtaGroupEntry 25}

mtaGroupSuccessfulConvertedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages that have been successfully
converted from one form to another in this group
since group creation."
::= {mtaGroupEntry 26}

mtaGroupFailedConvertedMessages OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of messages for which an unsuccessful
attempt was made to convert them from one form to
another in this group since group creation."
::= {mtaGroupEntry 27}

mtaGroupDescription OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A description of the group's purpose. This information is
intended to identify the group in a status display."
::= {mtaGroupEntry 28}

mtaGroupURL OBJECT-TYPE
SYNTAX URLString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A URL pointing to a description of the group. This
information is intended to identify and briefly describe
the group in a status display."
::= {mtaGroupEntry 29}

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mtaGroupCreationTime OBJECT-TYPE
SYNTAX TimeInterval
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Time since this group was first created."
::= {mtaGroupEntry 30}

mtaGroupHierarchy OBJECT-TYPE
SYNTAX INTEGER (-2147483648..2147483647)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Describes how this group fits into the hierarchy. A
positive value is interpreted as an mtaGroupIndex
value for some other group whose variables include
those of this group (and usually others). A negative
value is interpreted as a group collection code: Groups
with common negative hierarchy values comprise one
particular breakdown of MTA activity as a whole. A
zero value means that this MIB implementation doesn't
implement hierarchy indicators and thus the overall
group hierarchy cannot be determined."
::= {mtaGroupEntry 31}

mtaGroupOldestMessageId OBJECT-TYPE
SYNTAX SnmpAdminString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Message ID of the oldest message in the group's queue.
Whenever possible this should be in the form of an
RFC 822 msg-id; X.400 may convert X.400 message
identifiers to this form by following the rules laid
out in RFC2156."
::= {mtaGroupEntry 32}

mtaGroupLoopsDetected OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"A message loop is defined as a situation where the MTA
decides that a given message will never be delivered to
one or more recipients and instead will continue to
loop endlessly through one or more MTAs. This variable
counts the number of times the MTA has detected such a
situation in conjunction with something associated with

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RFC 2789 Mail Monitoring MIB March 2000

this group since group creation. Note that the
mechanism MTAs use to detect loops (e.g., trace field
counting, count of references to this MTA in a trace
field, examination of DNS or other directory information,
etc.), the level at which loops are detected (e.g., per
message, per recipient, per directory entry, etc.), and
the handling of a loop once it is detected (e.g., looping
messages are held, looping messages are bounced or sent
to the postmaster, messages that the MTA knows will loop
won't be accepted, etc.) vary widely from one MTA to the
next and cannot be inferred from this variable."
::= {mtaGroupEntry 33}

-- The mtaGroupAssociationTable provides a means of correlating
-- entries in the network services association table with the
-- MTA group responsible for the association.

mtaGroupAssociationTable OBJECT-TYPE
SYNTAX SEQUENCE OF MtaGroupAssociationEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding information regarding the associations
for each MTA group."
::= {mta 3}

mtaGroupAssociationEntry OBJECT-TYPE
SYNTAX MtaGroupAssociationEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The entry holding information regarding the associations
for each MTA group."
INDEX {applIndex, mtaGroupIndex, mtaGroupAssociationIndex}
::= {mtaGroupAssociationTable 1}

MtaGroupAssociationEntry ::= SEQUENCE {
mtaGroupAssociationIndex
INTEGER
}

mtaGroupAssociationIndex OBJECT-TYPE
SYNTAX INTEGER (1..2147483647)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Reference into association table to allow correlation of
this group's active associations with the association table."

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RFC 2789 Mail Monitoring MIB March 2000

::= {mtaGroupAssociationEntry 1}

-- The mtaGroupErrorTable gives each group a way of tallying
-- the specific errors it has encountered. The mechanism
-- defined here uses RFC 1893 status codes to identify
-- various specific errors. There are also classes for generic
-- errors of various sorts, and the entire mechanism is also
-- extensible, in that new error codes can be defined at any
-- time.

mtaGroupErrorTable OBJECT-TYPE
SYNTAX SEQUENCE OF MtaGroupErrorEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding information regarding accumulated errors
for each MTA group."
::= {mta 5}

mtaGroupErrorEntry OBJECT-TYPE
SYNTAX MtaGroupErrorEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The entry holding information regarding accumulated
errors for each MTA group."
INDEX {applIndex, mtaGroupIndex, mtaStatusCode}
::= {mtaGroupErrorTable 1}

MtaGroupErrorEntry ::= SEQUENCE {
mtaStatusCode
INTEGER (4000000..5999999),
mtaGroupInboundErrorCount
Counter32,
mtaGroupInternalErrorCount
Counter32,
mtaGroupOutboundErrorCount
Counter32
}

mtaGroupInboundErrorCount OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Count of the number of errors of a given type that have
been accumulated in association with a particular group
while processing incoming messages. In the case of SMTP

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RFC 2789 Mail Monitoring MIB March 2000

these will typically be errors reporting by an SMTP
server to the remote client; in the case of X.400
these will typically be errors encountered while
processing an incoming message."
::= {mtaGroupErrorEntry 1}

mtaGroupInternalErrorCount OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Count of the number of errors of a given type that have
been accumulated in association with a particular group
during internal MTA processing."
::= {mtaGroupErrorEntry 2}

mtaGroupOutboundErrorCount OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Count of the number of errors of a given type that have
been accumulated in association with a particular group's
outbound connection activities. In the case of an SMTP
client these will typically be errors reported while
attempting to contact or while communicating with the
remote SMTP server. In the case of X.400 these will
typically be errors encountered while constructing
or attempting to deliver an outgoing message."
::= {mtaGroupErrorEntry 3}

mtaStatusCode OBJECT-TYPE
SYNTAX INTEGER (4000000..5999999)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index capable of representing an Enhanced Mail System
Status Code. Enhanced Mail System Status Codes are
defined in RFC 1893. These codes have the form

class.subject.detail

Here 'class' is either 2, 4, or 5 and both 'subject' and
'detail' are integers in the range 0..999. Given a status
code the corresponding index value is defined to be
((class * 1000) + subject) * 1000 + detail. Both SMTP
error response codes and X.400 reason and diagnostic codes
can be mapped into these codes, resulting in a namespace

Freed & Kille Standards Track [Page 23]

RFC 2789 Mail Monitoring MIB March 2000

capable of describing most error conditions a mail system
encounters in a generic yet detailed way."
::= {mtaGroupErrorEntry 4}

-- Conformance information

mtaConformance OBJECT IDENTIFIER ::= {mta 4}

mtaGroups OBJECT IDENTIFIER ::= {mtaConformance 1}
mtaCompliances OBJECT IDENTIFIER ::= {mtaConformance 2}

-- Compliance statements

mtaCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 1566 implementations
which support the Mail Monitoring MIB for basic
monitoring of MTAs."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC1566Group}
::= {mtaCompliances 1}

mtaAssocCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 1566 implementations
which support the Mail Monitoring MIB for monitoring
of MTAs and their associations."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC1566Group, mtaRFC1566AssocGroup}
::= {mtaCompliances 2}

mtaRFC2249Compliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2249 implementations
which support the Mail Monitoring MIB for basic
monitoring of MTAs."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2249Group}
::= {mtaCompliances 5}

mtaRFC2249AssocCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2249 implementations

Freed & Kille Standards Track [Page 24]

RFC 2789 Mail Monitoring MIB March 2000

which support the Mail Monitoring MIB for monitoring of
MTAs and their associations."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2249Group, mtaRFC2249AssocGroup}
::= {mtaCompliances 6}

mtaRFC2249ErrorCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2249 implementations
which support the Mail Monitoring MIB for monitoring of
MTAs and detailed errors."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2249Group, mtaRFC2249ErrorGroup}
::= {mtaCompliances 7}

mtaRFC2249FullCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2249 implementations
which support the full Mail Monitoring MIB for
monitoring of MTAs, associations, and detailed errors."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2249Group, mtaRFC2249AssocGroup,
mtaRFC2249ErrorGroup}
::= {mtaCompliances 8}

mtaRFC2789Compliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2789 implementations
which support the Mail Monitoring MIB for basic
monitoring of MTAs."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2789Group}
::= {mtaCompliances 9}

mtaRFC2789AssocCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2789 implementations
which support the Mail Monitoring MIB for monitoring of
MTAs and their associations."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2789Group, mtaRFC2789AssocGroup}
::= {mtaCompliances 10}

mtaRFC2789ErrorCompliance MODULE-COMPLIANCE

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RFC 2789 Mail Monitoring MIB March 2000

STATUS current
DESCRIPTION
"The compliance statement for RFC 2789 implementations
which support the Mail Monitoring MIB for monitoring of
MTAs and detailed errors."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2789Group, mtaRFC2789ErrorGroup}
::= {mtaCompliances 11}

mtaRFC2789FullCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for RFC 2789 implementations
which support the full Mail Monitoring MIB for
monitoring of MTAs, associations, and detailed errors."
MODULE -- this module
MANDATORY-GROUPS {mtaRFC2789Group, mtaRFC2789AssocGroup,
mtaRFC2789ErrorGroup}
::= {mtaCompliances 12}

-- Units of conformance

mtaRFC1566Group OBJECT-GROUP
OBJECTS {
mtaReceivedMessages, mtaStoredMessages,
mtaTransmittedMessages, mtaReceivedVolume, mtaStoredVolume,
mtaTransmittedVolume, mtaReceivedRecipients,
mtaStoredRecipients, mtaTransmittedRecipients,
mtaGroupReceivedMessages, mtaGroupRejectedMessages,
mtaGroupStoredMessages, mtaGroupTransmittedMessages,
mtaGroupReceivedVolume, mtaGroupStoredVolume,
mtaGroupTransmittedVolume, mtaGroupReceivedRecipients,
mtaGroupStoredRecipients, mtaGroupTransmittedRecipients,
mtaGroupOldestMessageStored, mtaGroupInboundAssociations,
mtaGroupOutboundAssociations,
mtaGroupAccumulatedInboundAssociations,
mtaGroupAccumulatedOutboundAssociations,
mtaGroupLastInboundActivity, mtaGroupLastOutboundActivity,
mtaGroupRejectedInboundAssociations,
mtaGroupFailedOutboundAssociations,
mtaGroupInboundRejectionReason,
mtaGroupOutboundConnectFailureReason,
mtaGroupScheduledRetry, mtaGroupMailProtocol, mtaGroupName}
STATUS current
DESCRIPTION
"A collection of objects providing basic monitoring of MTAs.
This is the original set of such objects defined in RFC
1566."

Freed & Kille Standards Track [Page 26]

RFC 2789 Mail Monitoring MIB March 2000

::= {mtaGroups 10}

mtaRFC1566AssocGroup OBJECT-GROUP
OBJECTS {
mtaGroupAssociationIndex}
STATUS current
DESCRIPTION
"A collection of objects providing monitoring of MTA
associations. This is the original set of such objects
defined in RFC 1566."
::= {mtaGroups 11}

mtaRFC2249Group OBJECT-GROUP
OBJECTS {
mtaReceivedMessages, mtaStoredMessages,
mtaTransmittedMessages, mtaReceivedVolume, mtaStoredVolume,
mtaTransmittedVolume, mtaReceivedRecipients,
mtaStoredRecipients, mtaTransmittedRecipients,
mtaSuccessfulConvertedMessages, mtaFailedConvertedMessages,
mtaGroupReceivedMessages, mtaGroupRejectedMessages,
mtaGroupStoredMessages, mtaGroupTransmittedMessages,
mtaGroupReceivedVolume, mtaGroupStoredVolume,
mtaGroupTransmittedVolume, mtaGroupReceivedRecipients,
mtaGroupStoredRecipients, mtaGroupTransmittedRecipients,
mtaGroupOldestMessageStored, mtaGroupInboundAssociations,
mtaGroupOutboundAssociations, mtaLoopsDetected,
mtaGroupAccumulatedInboundAssociations,
mtaGroupAccumulatedOutboundAssociations,
mtaGroupLastInboundActivity, mtaGroupLastOutboundActivity,
mtaGroupLastOutboundAssociationAttempt,
mtaGroupRejectedInboundAssociations,
mtaGroupFailedOutboundAssociations,
mtaGroupInboundRejectionReason,
mtaGroupOutboundConnectFailureReason,
mtaGroupScheduledRetry, mtaGroupMailProtocol, mtaGroupName,
mtaGroupSuccessfulConvertedMessages,
mtaGroupFailedConvertedMessages, mtaGroupDescription,
mtaGroupURL, mtaGroupCreationTime, mtaGroupHierarchy,
mtaGroupOldestMessageId, mtaGroupLoopsDetected}
STATUS current
DESCRIPTION
"A collection of objects providing basic monitoring of MTAs.
This group was originally defined in RFC 2249."
::= {mtaGroups 4}

mtaRFC2249AssocGroup OBJECT-GROUP
OBJECTS {
mtaGroupAssociationIndex}

Freed & Kille Standards Track [Page 27]

RFC 2789 Mail Monitoring MIB March 2000

STATUS current
DESCRIPTION
"A collection of objects providing monitoring of MTA
associations. This group was originally defined in RFC
2249."
::= {mtaGroups 5}

mtaRFC2249ErrorGroup OBJECT-GROUP
OBJECTS {
mtaGroupInboundErrorCount, mtaGroupInternalErrorCount,
mtaGroupOutboundErrorCount}
STATUS current
DESCRIPTION
"A collection of objects providing monitoring of
detailed MTA errors. This group was originally defined
in RFC 2249."
::= {mtaGroups 6}

mtaRFC2789Group OBJECT-GROUP
OBJECTS {
mtaReceivedMessages, mtaStoredMessages,
mtaTransmittedMessages, mtaReceivedVolume, mtaStoredVolume,
mtaTransmittedVolume, mtaReceivedRecipients,
mtaStoredRecipients, mtaTransmittedRecipients,
mtaSuccessfulConvertedMessages, mtaFailedConvertedMessages,
mtaGroupReceivedMessages, mtaGroupRejectedMessages,
mtaGroupStoredMessages, mtaGroupTransmittedMessages,
mtaGroupReceivedVolume, mtaGroupStoredVolume,
mtaGroupTransmittedVolume, mtaGroupReceivedRecipients,
mtaGroupStoredRecipients, mtaGroupTransmittedRecipients,
mtaGroupOldestMessageStored, mtaGroupInboundAssociations,
mtaGroupOutboundAssociations, mtaLoopsDetected,
mtaGroupAccumulatedInboundAssociations,
mtaGroupAccumulatedOutboundAssociations,
mtaGroupLastInboundActivity, mtaGroupLastOutboundActivity,
mtaGroupLastOutboundAssociationAttempt,
mtaGroupRejectedInboundAssociations,
mtaGroupFailedOutboundAssociations,
mtaGroupInboundRejectionReason,
mtaGroupOutboundConnectFailureReason,
mtaGroupScheduledRetry, mtaGroupMailProtocol, mtaGroupName,
mtaGroupSuccessfulConvertedMessages,
mtaGroupFailedConvertedMessages, mtaGroupDescription,
mtaGroupURL, mtaGroupCreationTime, mtaGroupHierarchy,
mtaGroupOldestMessageId, mtaGroupLoopsDetected}
STATUS current
DESCRIPTION
"A collection of objects providing basic monitoring of MTAs.

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RFC 2789 Mail Monitoring MIB March 2000

This is the appropriate group for RFC 2789."
::= {mtaGroups 7}

mtaRFC2789AssocGroup OBJECT-GROUP
OBJECTS {
mtaGroupAssociationIndex}
STATUS current
DESCRIPTION
"A collection of objects providing monitoring of MTA
associations. This is the appropriate group for RFC
2789 association monitoring."
::= {mtaGroups 8}

mtaRFC2789ErrorGroup OBJECT-GROUP
OBJECTS {
mtaGroupInboundErrorCount, mtaGroupInternalErrorCount,
mtaGroupOutboundErrorCount}
STATUS current
DESCRIPTION
"A collection of objects providing monitoring of
detailed MTA errors. This is the appropriate group
for RFC 2789 error monitoring."
::= {mtaGroups 9}

END

5. Changes made since RFC 2249

This revision corrects a number of minor technical errors in the
construction of the mail monitoring MIB in RFC 2249 [18]:

(1) All DisplayStrings have been changed to SnmpAdminStrings,

(2) the conformance groups for different versions of this MIB have
been corrected,

(3) the required mtaStatusCode entry has been added to
MtaGroupErrorEntry (which does not affect the bits on the wire in
any way), and

(4) the recommendation that an empty string be returned if the last
operation was successful has been removed from
mtaGroupInboundRejectionReason and
mtaGroupOutboundConnectFailureReason as it conflicts with the
stated purpose of these variables.

Freed & Kille Standards Track [Page 29]

RFC 2789 Mail Monitoring MIB March 2000

6. Acknowledgements

This document is a work product of the Mail and Directory Management
(MADMAN) Working Group of the IETF. It is based on an earlier MIB
designed by S. Kille, T. Lenggenhager, D. Partain, and W. Yeong. The
Electronic Mail Association's TSC committee was instrumental in
providing feedback on and suggesting enhancements to RFC 1566 [19]
that have led to the present document.

7. References

[1] Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture for
Describing SNMP Management Frameworks", RFC 2571, April 1999.

[2] Rose, M. and K. McCloghrie, "Structure and Identification of
Management Information for TCP/IP-based Internets", STD 16, RFC
1155, May 1990.

[3] Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD 16,
RFC 1212, March 1991.

[4] Rose, M., "A Convention for Defining Traps for use with the
SNMP", RFC 1215, March 1991.

[5] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Structure of
Management Information Version 2 (SMIv2)", STD 58, RFC 2578,
April 1999.

[6] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Textual
Conventions for SMIv2", STD 58, RFC 2579, April 1999.

[7] McCloghrie, K., Perkins, D. and J. Schoenwaelder, "Conformance
Statements for SMIv2", STD 58, RFC 2580, April 1999.

[8] Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple
Network Management Protocol", STD 15, RFC 1157, May 1990.

[9] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Introduction to Community-based SNMPv2", RFC 1901, January
1996.

[10] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Transport
Mappings for Version 2 of the Simple Network Management Protocol
(SNMPv2)", RFC 1906, January 1996.

[11] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message
Processing and Dispatching for the Simple Network Management
Protocol (SNMP)", RFC 2572, April 1999.

Freed & Kille Standards Track [Page 30]

RFC 2789 Mail Monitoring MIB March 2000

[12] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM)
for version 3 of the Simple Network Management Protocol
(SNMPv3)", RFC 2574, April 1999.

[13] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser, "Protocol
Operations for Version 2 of the Simple Network Management
Protocol (SNMPv2)", RFC 1905, January 1996.

[14] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications", RFC
2573, April 1999.

[15] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access
Control Model (VACM) for the Simple Network Management Protocol
(SNMP)", RFC 2575, April 1999.

[16] Freed, N. and S. Kille, "Network Services Monitoring MIB", RFC
2788, March 2000.

[17] Wahl, M., Kille, S. and T. Howes, "Lightweight Directory Access
Protocol (v3): UTF-8 String Representation of Distinguished
Names", RFC 2253, December 1997.

[18] Freed, N. and S. Kille, "Mail Monitoring MIB", RFC 2249, January
1998.

[19] Freed, N. and S. Kille, "Mail Monitoring MIB", RFC 1566, January
1994.

[20] Kille, S., "Mapping between X.400(1988) and RFC 822/MIME", RFC
2156, January 1998.

[21] Crocker, D., "Standard for the Format of ARPA Internet Text
Message", STD 11, RFC 822, August 1982.

[22] Vaudreuil, G., "Enhanced Mail System Status Codes", RFC 1893,
January 1996.

8. Security Considerations

There are no management objects defined in this MIB that have a MAX-
ACCESS clause of read-write and/or read-create. So, if this MIB is
implemented correctly, then there is no risk that an intruder can
alter or create any management objects of this MIB via direct SNMP
SET operations.

Freed & Kille Standards Track [Page 31]

RFC 2789 Mail Monitoring MIB March 2000

However, this MIB does provide passive information about the
existence, type, and configuration of applications on a given host
that could potentially indicate some sort of vulnerability. Finally,
the information MIB provides about network usage could be used to
analyze network traffic patterns.

SNMPv1 by itself is not a secure environment. Even if the network
itself is secure (for example by using IPSec), even then, there is no
control as to who on the secure network is allowed to access and
GET/SET (read/change/create/delete) the objects in this MIB.

It is recommended that the implementers consider the security
features as provided by the SNMPv3 framework. Specifically, the use
of the User-based Security Model RFC 2574 [12] and the View-based
Access Control Model RFC 2575 [15] is recommended.

It is then a customer/user responsibility to ensure that the SNMP
entity giving access to an instance of this MIB, is properly
configured to give access to the objects only to those principals
(users) that have legitimate rights to indeed GET or SET
(change/create/delete) them.

9. Author and Chair Addresses

Ned Freed
Innosoft International, Inc.
1050 Lakes Drive
West Covina, CA 91790
USA

Phone: +1 626 919 3600
Fax: +1 626 919 3614
EMail: [email protected]

Steve Kille, MADMAN WG Chair
MessagingDirect Ltd.
The Dome, The Square
Richmond TW9 1DT
UK

Phone: +44 20 8332 9091
EMail: [email protected]

Freed & Kille Standards Track [Page 32]

RFC 2789 Mail Monitoring MIB March 2000

10. Full Copyright Statement

Copyright (C) The Internet Society (2000). All Rights Reserved.

This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.

The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.

This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

Funding for the RFC Editor function is currently provided by the
Internet Society.

Freed & Kille Standards Track [Page 33]