Network Working Group S. Kille, WG Chair Request for Comments: 1566 ISODE Consortium Category: Standards Track N. Freed, Editor Innosoft January 1994
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.
This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, this memo extends the basic Network Services Monitoring MIB [5] to allow monitoring of Message Transfer Agents (MTAs). It may also be used to monitor MTA components within gateways.
2. The SNMPv2 Network Management Framework
The SNMPv2 Network Management Framework consists of four major components. They are:
o RFC 1442 [1] which defines the SMI, the mechanisms used for describing and naming objects for the purpose of management.
o STD 17, RFC 1213 [2] defines MIB-II, the core set of managed objects for the Internet suite of protocols.
o RFC 1445 [3] which defines the administrative and other architectural aspects of the framework.
o RFC 1448 [4] 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 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.
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3. 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 occurs 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) Messages are converted into the format that's appropriate for the next hop.
(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.
4. MTA Objects
If there are one or more MTAs on the host, the following mta group may be used to monitor them. Any number of the MTAs on a host may be monitored. Each MTA is dealt with as a separate application 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 a separate document [5].
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5. Definitions
MTA-MIB DEFINITIONS ::= BEGIN
IMPORTS OBJECT-TYPE, Counter32, Gauge32 FROM SNMPv2-SMI DisplayString, TimeInterval FROM SNMPv2-TC mib-2 FROM RFC1213-MIB applIndex FROM APPLICATION-MIB;
mta MODULE-IDENTITY LAST-UPDATED "9311280000Z" ORGANIZATION "IETF Mail and Directory Management Working Group" CONTACT-INFO " Ned Freed
Postal: Innosoft International, Inc. 250 West First Street, Suite 240 Claremont, CA 91711 US
Tel: +1 909 624 7907 Fax: +1 909 621 5319
E-Mail: ned@innosoft.com" DESCRIPTION "The MIB module describing Message Transfer Agents (MTAs)" ::= { 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}
mtaReceivedMessages OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of messages received since MTA initialization." ::= {mtaEntry 1}
mtaStoredMessages OBJECT-TYPE SYNTAX Gauge32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of messages currently stored in the MTA." ::= {mtaEntry 2}
mtaTransmittedMessages OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of messages transmitted since MTA initialization." ::= {mtaEntry 3}
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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." ::= {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." ::= {mtaEntry 5}
mtaTransmittedVolume OBJECT-TYPE SYNTAX Counter32 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." ::= {mtaEntry 6}
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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 had no responsibility for should not be counted even if information about such recipients is available." ::= {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 had no responsibility for should not be counted." ::= {mtaEntry 8}
mtaTransmittedRecipients OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of recipients specified in all messages transmitted since MTA initialization. Recipients this MTA had no responsibility for should not be counted." ::= {mtaEntry 9}
-- MTAs typically group inbound reception, queue storage, and -- outbound transmission in some way. In the most extreme case -- 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.
-- 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.
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-- 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 all unused -- counters would be inaccessible; e.g., returning either a -- noSuchName error (for an SNMPv1 get), or a noSuchInstance -- exception (for an SNMPv2 get).
-- 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 differents "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 -- 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 abstration.
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}
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 MTA initialization." ::= {mtaGroupEntry 2}
mtaGroupRejectedMessages OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of messages rejected by this group since MTA initialization." ::= {mtaGroupEntry 3}
mtaGroupStoredMessages OBJECT-TYPE SYNTAX Gauge32 MAX-ACCESS read-only STATUS current DESCRIPTION "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 MTA initialization." ::= {mtaGroupEntry 5}
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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 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." ::= {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 DESCRIPTION "The total volume of messages transmitted by this group 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." ::= {mtaGroupEntry 8}
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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 MTA initialization. Recipients this MTA had 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 had 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 MTA initialization. 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 placed in the queue." ::= {mtaGroupEntry 12}
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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 MTA initialization, where the group is 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 MTA initialization, where the group 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 an outbound association for purposes of message delivery." ::= {mtaGroupEntry 18}
mtaGroupRejectedInboundAssociations OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of inbound associations the group has rejected, since MTA initialization." ::= {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 MTA initialization." ::= {mtaGroupEntry 20}
mtaGroupInboundRejectionReason OBJECT-TYPE SYNTAX DisplayString MAX-ACCESS read-only STATUS current DESCRIPTION "The failure reason, if any, for the last association this group refused to respond to. An empty string indicates that the last attempt was successful. If no association attempt has been made since the MTA was initializaed the value should be 'never'." ::= {mtaGroupEntry 21}
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mtaGroupOutboundConnectFailureReason OBJECT-TYPE SYNTAX DisplayString MAX-ACCESS read-only STATUS current DESCRIPTION "The failure reason, if any, for the last association attempt this group initiated. An empty string indicates that the last attempt was successful. 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 time when this group is scheduled to next 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, the IANA maintains a registry of the OIDs which correspond to well-known message transfer protocols. If the application protocol is not listed in the registry, an OID value of the form {applTCPProtoID port} or {applUDProtoID 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 group. applTCPProtoID and applUDPProtoID are defined in [5]." ::= {mtaGroupEntry 24}
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mtaGroupName OBJECT-TYPE SYNTAX DisplayString 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 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-1485. For X.400(1984) MTAs which do not have a Distinguished Name, the RFC-1327 syntax 'mta in globalid' should be used." ::= {mtaGroupEntry 25}
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}
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." ::= {mtaGroupAssociationEntry 1}
mtaCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for SNMPv2 entities which implement the Mail Monitoring MIB for basic monitoring of MTAs." MODULE -- this module MANDATORY-GROUPS {mtaGroup} ::= {mtaCompliances 1}
mtaAssocCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for SNMPv2 entities which implement the Mail Monitoring MIB for monitoring of MTAs and their associations." MODULE -- this module MANDATORY-GROUPS {mtaGroup, mtaAssocGroup} ::= {mtaCompliances 2}
mtaAssocGroup OBJECT-GROUP OBJECTS { mtaGroupAssociationIndex} STATUS current DESCRIPTION "A collection of objects providing monitoring of MTA associations." ::= {mtaGroups 2}
END
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6. Acknowledgements
This document is a product of the Mail and Directory Management (MADMAN) Working Group. It is based on an earlier MIB designed by S. Kille, T. Lenggenhager, D. Partain, and W. Yeong.
7. References
[1] 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.
[2] 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.
[3] Galvin, J., and K. McCloghrie, K., "Administrative Model for version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1445, Trusted Information Systems, Hughes LAN Systems, April 1993.
[4] 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.
[5] Kille, S., WG Chair, and N. Freed, Editor, "The Network Services Monitoring MIB", RFC 1565, ISODE Consortium, Innosoft, January 1994.
8. Security Considerations
Security issues are not discussed in this memo.
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9. Authors' Addresses
Steve Kille, WG Chair ISODE Consortium The Dome, The Square Richmond TW9 1DT UK
Phone: +44 81 332 9091 EMail: S.Kille@isode.com
Ned Freed, Editor Innosoft International, Inc. 250 West First Street, Suite 240 Claremont, CA 91711 USA
