Network Working Group S. Kille, WG Chair
Request for Comments: 1565 ISODE Consortium
Category: Standards Track N. Freed, Editor
Innosoft
January 1994

Network Services 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.

Table of Contents

1. IntrodUCtion ................................................. 2
2. The SNMPv2 Network Management Framework ...................... 2
2.1 Object Definitions .......................................... 3
3. Rationale for having a Network Services Monitoring MIB ....... 3
3.1 General Relationship to Other MIBs .......................... 4
3.2 Restriction of Scope ........................................ 4
3.3 Relationship to Directory Services .......................... 4
4. Application Objects .......................................... 5
5. Definitions .................................................. 6
6. Acknowledgements .............................................16
7. References ...................................................16
8. Security Considerations ......................................16
9. Authors' Addresses ...........................................17

1. Introduction

There are a wide range of networked applications for which it is
appropriate to provide SNMP Monitoring. This includes both TCP/IP
and OSI applications. This document defines a MIB which contains the
elements common to the monitoring of any network service application.
This information includes a table of all monitorable network service
applications, a count of the associations (connections) to each
application, and basic information about the parameters and status of
each application-related association.

This MIB may be used on its own for any application, and for most
simple applications this will suffice. This MIB is also designed to
serve as a building block which can be used in conjunction with
application-specific monitoring and management. Two examples of this
are MIBs defining additional variables for monitoring a Message
Transfer Agent (MTA) service or a Directory Service Agent (DSA)
service. It is eXPected that further MIBs of this nature will be
specified.

This MIB does not attempt to provide facilities for management of the
host or hosts the network service application runs on, nor does it
provide facilities for monitoring applications that provide something
other than a network service. Host resource and general application
monitoring is handled by the Host Resources MIB.

2. The SNMPv2 Network Management Framework

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

o RFC1442 [1] which defines the SMI, the mechanisms used for
describing and naming objects for the purpose of management.

o STD 17, RFC1213 [2] defines MIB-II, the core set of managed
objects for the Internet suite of protocols.

o RFC1445 [3] which defines the administrative and other
architectural ASPects of the framework.

o RFC1448 [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.

3. Rationale for having a Network Services Monitoring MIB

Much effort has been expended in developing tools to manage lower
layer network facilities. However, relatively little work has been
done on managing application layer entities. It is neither efficient
nor reasonable to manage all aspects of application layer entities
using only lower layer information. Moreover, the difficulty of
managing application entities in this way increases dramatically as
application entities become more complex.

This leads to a substantial need to monitor applications which
provide network services, particularly distributed components such as
MTAs and DSAs, by monitoring specific aspects of the application
itself. Reasons to monitor such components include but are not
limited to measuring load, detecting broken connectivity, isolating
system failures, and locating congestion.

In order to manage network service applications effectively two
requirements must be met:

(1) It must be possible to monitor a large number of components
(typical for a large organization).

(2) Application monitoring must be integrated into general
network management.

This specification defines simple read-only access; this is
sufficient to determine up/down status and provide an indication of a
broad class of operational problems.

3.1 General Relationship to Other MIBs

This MIB is intended to only provide facilities common to the
monitoring of any network service application. It does not provide
all the facilities necessary to monitor any specific application.
Each specific type of network service application is expected to have
a MIB of its own that makes use of these common facilities.

3.2 Restriction of Scope

The framework provided here is very minimal; there is a lot more that
could be done. For example:

(1) General network service application configuration monitoring and
control.

(2) Detailed examination and modification of individual entries in
service-specific request queues.

(3) Probing to determine the status of a specific request (e.g. the
location of a mail message with a specific message-id).

(4) Requesting that certain actions be performed (e.g. forcing an
immediate connection and transfer of pending messages to some
specific system).

All these capabilities are both impressive and useful. However,
these capabilities would require provisions for strict security
checking. These capabilities would also mandate a much more complex
design, with many characteristics likely to be fairly
implementation-specific. As a result such facilities are likely to
be both contentious and difficult to implement.

This document religiously keeps things simple and focuses on the
basic monitoring aspect of managing applications providing network
services. The goal here is to provide a framework which is simple,
useful, and widely implementable.

3.3 Relationship to Directory Services

Use of and management of directory services already is tied up with
network service application management. There are clearly many
things which could be dealt with by directory services and protocols.
We take the line here that static configuration information is both
provided by and dealt with by directory services and protocols. The
emphasis here is on transient application status.

By placing static information in the directory, the richness and
linkage of the directory information framework does not need to be
repeated in the MIB. Static information is information which has a
mean time to change of the order of days or longer.

When information about network service applications is stored in the
directory (regardless of whether or not the network service
application makes direct use of the directory), it is recommended
that a linkage be established, so that:

(1) The managed object contains its own directory name. This allows
all directory information to be oBTained by reference. This will
let a SNMP monitor capable of performing directory queries
present this information to the manager in an appropriate format.
It is intended that this will be the normal case.

(2) The directory will reference the location of the SNMP agent, so
that an SNMP capable directory query agent could probe dynamic
characteristics of the object.

(3) This approach could be extended further, so that the SNMP
attributes are modelled as directory attributes. This would
dramatically simplify the design of directory service agents that
use SNMP to obtain the information they need.

4. Application Objects

This MIB defines a set of general purpose attributes which would be
appropriate for a range of applications that provide network
services. Both OSI and non-OSI services can be accomodated.
Additional tables defined in extensions to this MIB provide
attributes specific to specific network services.

A table is defined which will have one row for each network service
application running on the system. The only static information held
on the application is its name. All other static information should
be obtained from various directory services. The applDirectoryName
is an external key, which allows an SNMP MIB entry to be cleanly
related to the X.500 Directory. In SNMP terms, the applications are
grouped in a table called applTable, which is indexed by an integer
key applIndex.

The type of the application will be determined by one or both of:

(1) Additional MIB variables specific to the applications.

(2) An association to the application of a specific protocol.

5. Definitions

APPLICATION-MIB DEFINITIONS ::= BEGIN

IMPORTS
OBJECT-TYPE, Counter32, Gauge32
FROM SNMPv2-SMI
mib-2
FROM RFC1213-MIB
DisplayString, TimeStamp
FROM SNMPv2-TC;

-- Textual conventions

-- DistinguishedName [5] is used to refer to objects in the
-- directory.

DistinguishedName ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"A Distinguished Name represented in accordance with
RFC1485."
SYNTAX DisplayString

application 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 network service applications"
::= { mib-2 27 }

-- The basic applTable contains a list of the application
-- entities.

applTable OBJECT-TYPE
SYNTAX SEQUENCE OF ApplEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding objects which apply to all different
kinds of applications providing network services."
::= {application 1}

applEntry OBJECT-TYPE
SYNTAX ApplEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry associated with a network service application."
INDEX {applIndex}
::= {applTable 1}

ApplEntry ::= SEQUENCE {
applIndex
INTEGER,
applName
DisplayString,
applDirectoryName
DistinguishedName,
applVersion
DisplayString,
applUptime
TimeStamp,
applOperStatus
INTEGER,
applLastChange
TimeStamp,
applInboundAssociations
Gauge32,
applOutboundAssociations
Gauge32,
applAccumulatedInboundAssociations
Counter32,
applAccumulatedOutboundAssociations
Counter32,
applLastInboundActivity
TimeStamp,
applLastOutboundActivity
TimeStamp,
applRejectedInboundAssociations
Counter32,
applFailedOutboundAssociations

Counter32
}

applIndex OBJECT-TYPE
SYNTAX INTEGER (1..2147483647)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index to uniquely identify the network service
application."
::= {applEntry 1}

applName OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The name the network service application chooses to be
known by."
::= {applEntry 2}

applDirectoryName OBJECT-TYPE
SYNTAX DistinguishedName
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The Distinguished Name of the directory entry where
static information about this application is stored.
An empty string indicates that no information about
the application is available in the directory."
::= {applEntry 3}

applVersion OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The version of network service application software."
::= {applEntry 4}

applUptime OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time the network service
application was last initialized. If the application was
last initialized prior to the last initialization of the
network management subsystem, then this object contains
a zero value."
::= {applEntry 5}

applOperStatus OBJECT-TYPE
SYNTAX INTEGER {
up(1),
down(2),
halted(3),
congested(4),
restarting(5)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Indicates the operational status of the network service
application. 'down' indicates that the network service is
not available. 'running' indicates that the network service
is operational and available. 'halted' indicates that the
service is operational but not available. 'congested'
indicates that the service is operational but no additional
inbound associations can be accomodated. 'restarting'
indicates that the service is currently unavailable but is
in the process of restarting and will be available soon."
::= {applEntry 6}

applLastChange OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time the network service
application entered its current operational state. If
the current state was entered prior to the last
initialization of the local network management subsystem,
then this object contains a zero value."
::= {applEntry 7}

applInboundAssociations OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of current associations to the network service
application, where it is the responder. For dynamic single
threaded processes, this will be the number of application
instances."
::= {applEntry 8}

applOutboundAssociations OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of current associations to the network service
application, where it is the initiator. For dynamic single
threaded processes, this will be the number of application
instances."
::= {applEntry 9}

applAccumulatedInboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of associations to the application entity
since application initialization, where it was the responder.
For dynamic single threaded processes, this will be the
number of application instances."
::= {applEntry 10}

applAccumulatedOutboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of associations to the application entity
since application initialization, where it was the initiator.
For dynamic single threaded processes, this will be the
number of application instances."
::= {applEntry 11}

applLastInboundActivity OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time this application last
had an inbound association. If the last association
occurred prior to the last initialization of the network
subsystem, then this object contains a zero value."
::= {applEntry 12}

applLastOutboundActivity OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time this application last
had an outbound association. If the last association
occurred prior to the last initialization of the network
subsystem, then this object contains a zero value."
::= {applEntry 13}

applRejectedInboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number of inbound associations the application
entity has rejected, since application initialization."
::= {applEntry 14}

applFailedOutboundAssociations OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The total number associations where the application entity
is initiator and association establishment has failed,
since application initialization."
::= {applEntry 15}

-- The assocTable augments the information in the applTable
-- with information about associations. Note that two levels
-- of compliance are specified below, depending on whether
-- association monitoring is mandated.

assocTable OBJECT-TYPE
SYNTAX SEQUENCE OF AssocEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The table holding a set of all active application
associations."
::= {application 2}

assocEntry OBJECT-TYPE
SYNTAX AssocEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry associated with an association for a network
service application."
INDEX {applIndex, assocIndex}
::= {assocTable 1}

AssocEntry ::= SEQUENCE {
assocIndex
INTEGER,
assocRemoteApplication
DisplayString,
assocApplicationProtocol
OBJECT IDENTIFIER,
assocApplicationType
INTEGER,
assocDuration
TimeStamp
}

assocIndex OBJECT-TYPE
SYNTAX INTEGER (1..2147483647)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index to uniquely identify each association for a network
service application."
::= {assocEntry 1}

assocRemoteApplication OBJECT-TYPE
SYNTAX DisplayString
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The name of the system running remote network service
application. For an IP-based application this should be
either a domain name or IP address. For an OSI application
it should be the string encoded distinguished name of the
managed object. For X.400(84) MTAs which do not have a
Distinguished Name, the RFC1327 [6] syntax
'mta in globalid' should be used."
::= {assocEntry 2}

assocApplicationProtocol OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An identification of the protocol being used for the
application. For an OSI Application, this will be the
Application Context. For Internet applications, the IANA
maintains a registry of the OIDs which correspond to
well-known applications. 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 protocol."
::= {assocEntry 3}

assocApplicationType OBJECT-TYPE
SYNTAX INTEGER {
ua-initiator(1),
ua-responder(2),
peer-initiator(3),
peer-responder(4)}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This indicates whether the remote application is some type of
client making use of this network service (e.g. a User Agent)
or a server acting as a peer. Also indicated is whether the
remote end initiated an incoming connection to the network
service or responded to an outgoing connection made by the
local application."
::= {assocEntry 4}

assocDuration OBJECT-TYPE
SYNTAX TimeStamp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of sysUpTime at the time this association was
started. If this association started prior to the last
initialization of the network subsystem, then this
object contains a zero value."
::= {assocEntry 5}

-- Conformance information

applConformance OBJECT IDENTIFIER ::= {application 3}

applGroups OBJECT IDENTIFIER ::= {applConformance 1}
applCompliances OBJECT IDENTIFIER ::= {applConformance 2}

-- Compliance statements

applCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMPv2 entities
which implement the Network Services Monitoring MIB
for basic monitoring of network service applications."
MODULE -- this module
MANDATORY-GROUPS {applGroup}
::= {applCompliances 1}

assocCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMPv2 entities which
implement the Network Services Monitoring MIB for basic
monitoring of network service applications and their
associations."
MODULE -- this module
MANDATORY-GROUPS {applGroup, assocGroup}
::= {applCompliances 2}

-- Units of conformance

applGroup OBJECT-GROUP
OBJECTS {
applName, applVersion, applUptime, applOperStatus,
applLastChange, applInboundAssociations,
applOutboundAssociations, applAccumulatedInboundAssociations,
applAccumulatedOutboundAssociations, applLastInboundActivity,
applLastOutboundActivity, applRejectedInboundAssociations,
applFailedOutboundAssociations}
STATUS current
DESCRIPTION
"A collection of objects providing basic monitoring of
network service applications."
::= {applGroups 1}

assocGroup OBJECT-GROUP
OBJECTS {
assocRemoteApplication, assocApplicationProtocol,
assocApplicationType, assocDuration}
STATUS current
DESCRIPTION
"A collection of objects providing basic monitoring of
network service applications' associations."
::= {applGroups 2}

-- OIDs of the form {applTCPProtoID port} are intended to be used
-- for TCP-based protocols that don't have OIDs assigned by other
-- means. {applUDPProtoID port} serves the same purpose for
-- UDP-based protocols. In either case 'port' corresponds to
-- the primary port number being used by the protocol. For example,
-- assuming no other OID is assigned for SMTP, an OID of
-- {applTCPProtoID 25} could be used, since SMTP is a TCP-based
-- protocol that uses port 25 as its primary port.

applTCPProtoID OBJECT IDENTIFIER ::= {application 4}
applUDPProtoID OBJECT IDENTIFIER ::= {application 5}

END

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)", RFC1442, 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, RFC1213, Hughes LAN Systems, Performance Systems
International, March 1991.

[2] Galvin, J., and K. McCloghrie, "Administrative Model for version
2 of the Simple Network Management Protocol (SNMPv2)", RFC1445,
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)", RFC1448, SNMP Research, Inc., Hughes LAN
Systems, Dover Beach Consulting, Inc., Carnegie Mellon
University, April 1993.

[5] Kille, S., "A String Representation of Distinguished Names", RFC
1485, ISODE Consortium, July 1993.

[6] Kille, S., "Mapping between X.400(1988) / ISO 10021 and RFC822",
RFC1327, University College London, May 1992.

8. Security Considerations

Security issues are not discussed in this memo.

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

Phone: +1 909 624 7907
Fax: +1 909 621 5319
EMail: ned@innosoft.com