One document matched: draft-ietf-opsawg-operations-and-management-04.txt
Differences from draft-ietf-opsawg-operations-and-management-03.txt
Network Working Group D. Harrington
Internet-Draft Huawei Technologies USA
Intended status: BCP July 14, 2008
Expires: January 15, 2009
Guidelines for Considering Operations and Management of New Protocols
draft-ietf-opsawg-operations-and-management-04
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Abstract
New protocols or protocol extensions are best designed with due
consideration of functionality needed to operate and manage the
protocol. Retrofitting operations and management is sub-optimal.
The purpose of this document is to provide guidance to authors and
reviewers of documents defining new protocols or protocol extensions,
covering aspects of operations and management that should be
considered.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Design for Operations and Management . . . . . . . . . . . . . 4
2.1. IETF Management Framework . . . . . . . . . . . . . . . . 4
3. Operational Considerations . . . . . . . . . . . . . . . . . . 5
3.1. Operations Model . . . . . . . . . . . . . . . . . . . . . 6
3.2. Installation and Initial Setup . . . . . . . . . . . . . . 7
3.3. Migration Path . . . . . . . . . . . . . . . . . . . . . . 8
3.4. Requirements on Other Protocols and Functional
Components . . . . . . . . . . . . . . . . . . . . . . . . 8
3.5. Impact on Network Operation . . . . . . . . . . . . . . . 9
3.6. Verifying Correct Operation . . . . . . . . . . . . . . . 10
4. Management Considerations . . . . . . . . . . . . . . . . . . 10
4.1. Interoperability . . . . . . . . . . . . . . . . . . . . . 11
4.2. Management Information . . . . . . . . . . . . . . . . . . 13
4.3. Fault Management . . . . . . . . . . . . . . . . . . . . . 14
4.3.1. Liveness Detection and Monitoring . . . . . . . . . . 15
4.3.2. Fault Determination . . . . . . . . . . . . . . . . . 15
4.3.3. Fault Isolation . . . . . . . . . . . . . . . . . . . 16
4.3.4. Corrective Action . . . . . . . . . . . . . . . . . . 16
4.4. Configuration Management . . . . . . . . . . . . . . . . . 16
4.4.1. Verifying Correct Operation . . . . . . . . . . . . . 18
4.4.2. Control of Function and Policy . . . . . . . . . . . . 18
4.5. Accounting Management . . . . . . . . . . . . . . . . . . 18
4.6. Performance Management . . . . . . . . . . . . . . . . . . 19
4.7. Security Management . . . . . . . . . . . . . . . . . . . 20
5. Documentation Guidelines . . . . . . . . . . . . . . . . . . . 22
5.1. Recommended Discussions . . . . . . . . . . . . . . . . . 22
5.2. Null Manageability Considerations Sections . . . . . . . . 23
5.3. Placement of Operations and Manageability
Considerations Sections . . . . . . . . . . . . . . . . . 23
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
7. Security Considerations . . . . . . . . . . . . . . . . . . . 23
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 24
9. Informative References . . . . . . . . . . . . . . . . . . . . 24
Appendix A. Review Checklist . . . . . . . . . . . . . . . . . . 26
A.1. General Document Checklist . . . . . . . . . . . . . . . . 27
A.2. Operations and Management Checklist . . . . . . . . . . . 27
Appendix B. Open Issues . . . . . . . . . . . . . . . . . . . . . 28
Appendix C. DISCUSSES that have yet to be discussed . . . . . . . 28
Appendix D. Change Log . . . . . . . . . . . . . . . . . . . . . 31
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1. Introduction
Often when new protocols or protocol extensions are developed, not
enough consideration is given to how the protocol will be deployed,
operated and managed. Retrofitting operations and management
mechanisms is often hard and architecturally unpleasant, and certain
protocol design choices may make deployment, operations, and
management particularly hard. Since the ease of operations and
management may impact the success of IETF protocols, this document
provides guidelines to help protocol designers and working groups
consider the operations and management functionality needed by their
new IETF protocol or protocol extension at an earlier phase.
This document suggests protocol designers to consider operations and
management needs and then recommend appropriate standard management
protocols and data models to address the relevant operations and
management needs. This is similar to a WG considering which security
threats are relevant to their protocol, and then recommending
appropriate standard security protocols to mitigate the relevant
threats.
This document discusses the importance of considering operations and
management. Section 1 introduces the subject and section 2 describes
the IETF Management Framework. Section 3 discusses operational
functionality to consider. Section 4 discusses management
functionality to consider.
This document sets forth a list of subjective guidelines and a list
of objective criteria by which a protocol designer can evaluate
whether the protocol that he/she has developed addresses common
operations and management needs. Operations and management is highly
dependent on the environment in which it is used, so most guidelines
are subjective rather than objective.
We provide some objective criteria to promote interoperability
through the use of standard management interfaces, such as "did you
design counters in a MIB module for monitoring packets in/out of an
interface?" [RFC2863], "did you write an XML-based data model for
configuring your protocol with Netconf?" [RFC4741], and "did you
standardize syslog message content and structured data elements for
reporting events that might occur when operating your protocol?"
[I-D.ietf-syslog-protocol] and "did you consider appropriate
notifications in case of failure situations??
This document only provides guidelines; it does not specify how the
guidelines provided should be used within the IETF.
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1.1. Terminology
This document deliberately does not use the (capitalized) key words
described in RFC 2119 [RFC2119]. RFC 2119 states the keywords must
only be used where it is actually required for interoperation or to
limit behavior which has potential for causing harm (e.g., limiting
retransmissions). For example, they must not be used to try to
impose a particular method on implementers where the method is not
required for interoperability. This document is a set of guidelines
based on current practices of protocol designers and operators. This
document does not describe requirements, so the key words from
RFC2119 have no place here.
o "new protocol" includes new protocols, protocol extensions, data
models, or other functionality being designed.
o "protocol designer" represents individuals and working groups
involved in the development of new protocols.
o [DISCUSS] markers indicate a lack of consensus on what should be
written.
o [TODO] markers indicate the editor has a reasonable understanding
of what needs to be (re-)written. Contributions of text would be
welcome.
o Note to RFC Editor - All [DISCUSS] or [TODO] marks should be
resolved before RFC publication. If any still exist, including in
the Terminology section, then please return the document to the
editor for resolution.
2. Design for Operations and Management
"Design for operations and management" means that the operational
environment and manageability of the protocol should be considered
from the start when new protocols are designed.
When a WG considers operation and management functionality for a
protocol, the document should contain enough information to
understand how the protocol will be deployed and managed, but the WG
should expect that considerations for operations and management may
need to be updated in the future, after further operational
experience has been gained.
2.1. IETF Management Framework
For years the IETF has stressed the use of the IETF Standard
Management Framework and SMI MIB modules [RFC2578] for managing new
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protocols. The IETF designed the Standard Management Framework and
SMI MIB modules to permit multiple protocols to utilize the MIB data
[RFC1052], but it became a common misunderstanding that a MIB module
could only be used with the SNMP protocol (described in [RFC3410] and
associated documents).
In 2001, OPS Area design teams were created to document requirements
related to configuration of IP-based networks. One output was
"Requirements for Configuration Management of IP-based Networks"
[RFC3139].
In 2003, the Internet Architecture Board (IAB) held a workshop on
Network Management [RFC3535] that discussed the strengths and
weaknesses of some IETF network management protocols, and compared
them to operational needs, especially configuration.
One factor discussed was the user-unfriendliness of the binary format
of SNMP and COPS-PR [RFC3084], and it was recommended that the IETF
explore an XML-based Structure of Management Information, and an XML-
based protocol for configuration.
Another factor discussed was that deployed tools for event/alarm
correlation, root cause analysis and logging are not sufficient, and
there is a need to support a human interface and a programmatic
interface. The IETF decided to standardize aspects of the de facto
standard for system logging, especially security and the need for
better programmatic support.
In 2006, the IETF discussed whether the Management Framework should
be updated to accommodate multiple IETF standard SMI languages, and
multiple IETF standard protocols for doing network management.
This document provides some initial guidelines for considering
operations and management in an IETF Management Framework that
consists of multiple protocols and multiple data models, with an eye
toward being flexible while also striving for interoperability.
3. Operational Considerations
Designers of a new protocol should carefully consider the operational
aspects. A protocol that is defined very precisely in a well-written
document does not guarantee that it is going to be deployable in the
real world. Operational aspects will have a serious impact on the
actual success of a protocol. Such aspects include bad interactions
with existing solutions, a difficult upgrade path, difficulty of
debugging problems, difficulty configuring from a central database,
or a complicated state diagram that operations staff will find
difficult to understand
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BGP flap damping [RFC2439] is an example. It was designed to block
high frequency route flaps, however the design did not consider the
existence of BGP path exploration/slow convergence. In real
operations, people observed the loss of reach-ability due to false
flap damping that are caused by path exploration. As a result, most
places turned flap damping off. RIPE even issued official
recommendation for turning it off.
[DISCUSS: examples, list of current protocols characteristics and
their impact on the network. e.g., burst traffic impact on network
congestion.]
IPFIX contains congestion awareness enhancements for controlling the
impact of the protocol on the network.
3.1. Operations Model
Protocol designers can analyze the operational environment and mode
of work in which the new protocol or extension will work. Such an
exercise needs not be reflected directly by text in their document,
but could help in visualizing the operational model related to the
applicability of the protocol in the Internet environments where it
will be deployed. The operational model should take into account
factors such as:
o what type of management entities will be involved (agents, network
management systems)?
o what is the possible architecture (client-server, manager-agent,
polling-driven or event-driven, autoconfiguration, two levels or
hierarchical)?
o what are the management operations - initial configuration,
dynamic configuration, alarms and exceptions reporting, logging,
performance monitoring, performance reporting, debugging?
o how are these operations performed - locally, remotely, atomic
operation, scripts? Are they performed immediately or time
scheduled or event triggered?
o what are the typical user interfaces - Command line (CLI) or
graphical user interface (GUI)?
Protocol designers should consider how the new protocol will be
managed in different deployment scales. It might be sensible to use
a local management interface to manage the new protocol on a single
device, but in a large network, remote management using a centralized
server and/or using distributed management functionality might make
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more sense. Auto-configuration and default parameters might be
possible for some new protocols.
There may be a need to support a human interface, e.g., for
troubleshooting, and a programmatic interface, e.g., for automated
monitoring and root cause analysis. It might be important that the
internal method routines used by the application programming
interfaces and the human interfaces should be the same to ensure that
data exchanged between these two interfaces is always consistent.
Mixing methods leads to inconsistency, so identifying consistent
methods of retrieving information is relevant. [DISCUSS: would the
example of inconsistency between MIB counters that cannot be reset
and CLI counters that can be rest be useful here?]
Protocol designers should consider what management operations are
expected to be performed as a result of the deployment of the
protocol - such as whether write operations will be allowed on
routers and on hosts, or if notifications for alarms or other events
will be expected.
3.2. Installation and Initial Setup
Protocol designers should consider default values that make sense
from the protocol objectives, so as to simplify configuration,
including default modes and parameters. For example, it could be
helpful or necessary to specify default values for modes, timers,
default state of logical control variables, default transports, and
so on. Even if default values are used, it must be possible to
retrieve all the actual values or at least an indication that known
default values are being used.
Protocol designers should consider how to enable operators to
concentrate on the configuration of the network as a whole rather
than individual devices.
It is desirable to discuss the background of chosen default values,
or perhaps why a range of values makes sense. In many cases, when
technology changes, the values in an RFC might make less and less
sense. It is very useful to understand whether defaults are based on
best current practice and are expected to change as technologies
advance or whether they have a more universal value that should not
be changed lightly. For example, the default interface speed might
be expected to change over time due to increased speeds in the
network, and cryptographical algorithms might be expected to change
over time as older algoithms are "broken".
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it is extremely important to set a sensible default value for all
parameters
the default value should stay on the conservative side rather than
on the "optimizing performance" side. (example: the initial RTT
and RTTvar values of a TCP connection)
for those parameters that are speed-dependent, instead of using a
constant, try to set the default value as a function of the link
speed or some other relevant factors. This would help reduce the
chance of technology-advancement causing problems.
3.3. Migration Path
If the new protocol is a new version of an existing protocol, or is
replacing another technology, the protocol designer should consider
how deployments should transition to the new protocol. This should
include co-existence with previously deployed protocols and/or
previous versions of the same protocol, incompatibilities between
versions, translation between versions, and side effects that might
occur. Are older protocols or versions disabled or do they co-exist
in the network with the new protocol?
Another point to consider is extensibility of the management approach
- How open to future protocol extensions are the management
techniques you are defining? [DISCUSS: this could use a good example
of when a protocol designer should consider future extensions to the
management. Are we talking about writing extensible data models? ]
3.4. Requirements on Other Protocols and Functional Components
Protocol designers should consider the requirements that the new
protocol might put on other protocols and functional components, and
should also document the requirements from other protocols that have
been considered in designing the new protocol.
These considerations should generally remain illustrative to avoid
creating restrictions or dependencies, or potentially impacting the
behavior of existing protocols, or restricting the extensibility of
other protocols, or assuming other protocols will not be extended in
certain ways.
For example, when RSVP [RFC2205] was designed, each router looked at
the RSVP PATH message, and if the router understood RSVP, it would
adds its own address to the message to enable automatically tunneling
thru non-RSVP routers. But in reality routers cannot look at an
otherwise normal IP packet, and potentially take it off the fast
path! The initial designers overlooked that a new requirement was
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being put on the functional components of a router. The "router
alert" option was finally developed to solve this problem for RSVP
and other protocols that require the router take some packets off the
fast forwarding path.
3.5. Impact on Network Operation
The introduction of a new protocol or extensions to an existing
protocol may have an impact on the operation of existing networks.
Protocol designers should outline such impacts (which may be
positive) including scaling concerns and interactions with other
protocols. For example, a new protocol that doubles the number of
active, reachable addresses in use within a network might need to be
considered in the light of the impact on the scalability of the IGPs
operating within the network.
A protocol could send active monitoring packets on the wire. If we
don't pay attention, we might get very good accuracy, but at the cost
of using all the available bandwidth.
The protocol designer should consider the potential impact on the
behavior of other protocols in the network and on the traffic levels
and traffic patterns that might change, including specific types of
traffic such as multicast. Also consider the need to install new
components that are added to the network as result of the changes in
the operational model, such as servers performing auto-configuration
operations.
The protocol designer should consider also the impact on
infrastructure applications like the DNS [RFC1034], registries, or
the size of routing tables. For example, SMTP [RFC2821] servers use
a reverse DNS lookup to filter out incoming connection requests.
When Berkeley installed a new spam filter, their mail server stopped
functioning because of the DNS cache resolver overload.
The impact on performance may also be noted - increased delay or
jitter in real-time traffic applications, or response time in client-
server applications when encryption or filtering are applied.
It must be easy to do consistency checks of versions/revisions of
configurations over time. People tend to be lazy and change
configuration on routers but not update the database. A system
better mandate database-driven configuration to reduce configuration
errors/ inconsistencies. [DISCUSS: is this paragraph really about
protocol design for operability or about operational practice? If
this stays, it probably needs a bit more discussion on database
driven configurations, and how protocol design would be impacted by
the expectation of database-driven configuration. ]
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It must be easy to do consistency checks of configurations between
the ends of a link in order to determine the differences between two
configurations and whether the configurations are consistent.
[DISCUSS: this needs rewording to better describe consistency
checking 1) over time, and 2) between ends of a link. probably needs
a bit more discussion on the need to be able to understand and check
what it is happening on the wire actually matches what the Operator
tried to configure. Basically, complexity is your enemy here, and
that cannot be stressed often enough (no idea how you can verify
whether for example a SIP application is actually doing what it is
supposed to do due to the complexity).]
It is important to minimize the impact caused by configuration
changes. Given configuration A and configuration B, it should be
possible to generate the operations necessary to get from A to B with
minimal state changes and effects on network and systems.
3.6. Verifying Correct Operation
The protocol designer should consider techniques for testing the
effect that the protocol has had on the network by sending data
through the network and observing its behavior (aka active
monitoring). Protocol designers should consider how the correct end-
to-end operation of the new protocol in the network can be tested
actively and passively, and how the correct data or forwarding plane
function of each network element can be verified to be working
properly with the new protocol. Which metrics are of interest?
4. Management Considerations
The considerations of manageability should start from describing the
operational model, which includes identifying the entities to be
managed, how the respective protocol is supposed to be installed,
configured and monitored, who are the managers and what type of
management interfaces and protocols they would use.
Considerations for management should include a discussion of what
needs to be managed, and how to achieve various management tasks.
The "write a MIB module" approach to considering management often
focuses on monitoring a protocol endpoint on a single device. A MIB
module document typically only considers monitoring properties
observable at one end, while the document does not really cover
managing the *protocol* (the coordination of multiple ends), and does
not even come near managing the *service* (which includes a lot of
stuff that is very far away from the box). This is exactly what
operators hate - you need to be able to manage both ends. As
[RFC3535] says, MIB modules can often be characterized as a list of
ingredients without a recipe.
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Management needs to be considered not only from the perspective of a
device, but also from the perspective of network and service
management perspectives. Often a network element is not aware of the
service being delivered.
[DISCUSS: Is a section on P2P vs. central management called for
here?]
WGs should consider how to configure multiple related/co-operating
devices and how to back off if one of those configurations fails or
causes trouble. NETCONF addresses this in a generic manner by
allowing an operator to lock the configuration on multiple devices,
perform the configuration settings/changes, check that they are OK
(undo if not) and then unlock the devices.
Techniques for debugging protocol interactions in a network must be
part of the network management discussion. Implementation source
code should be debugged before ever being added to a network, so
asserts and memory dumps do not normally belong in management data
models. However, debugging on-the-wire interactions is a protocol
issue: it is enormously helpful if a protocol has hooks to make
debugging of network interactions easy, and/or is designed in such a
way that debugging protocol behaviors is easy. Hand-waving this away
is not something that operators like ...
In a client/server protocol, it may be more important to instrument
the server end of a protocol than the client end.
4.1. Interoperability
Just as when deploying protocols that will inter-connect devices, our
primary goal in considering management should be interoperability,
whether across devices from different vendors, across models from the
same vendor, or across different releases of the same product.
Some product designers and protocol designers assume that if a device
can be managed individually using a command line interface or a web
page interface, that such a solution is enough. But when equipment
from multiple vendors is combined into a large network, scalability
of management becomes a problem. It is important to have consistency
in the management interfaces so network-wide operational processes
can be automated. For example, a single switch might be easily
managed using an interactive web interface when installed in a single
office small business, but when, say, a fast food company installs
similar switches from multiple vendors in hundreds or thousands of
individual branches and wants to automate monitoring them from a
central location, monitoring vendor-and-model-specific web pages
would be difficult to automate.
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Getting everybody to agree on a certain syntax and the protocol
associated with that has proven to be difficult. So management
systems tend to speak whatever the boxes support, whether the IETF
likes this or not. The IETF is moving from support for a single
management data modeling language (SMI [RFC2578]) and a single
management protocol (SNMP [RFC3410]) towards support for additional
management protocols and data models suited to different purposes,
such as configuration (netconf [RFC4741]), usage accounting (IPFIX
[RFC5105]), and logging (syslog [I-D.ietf-syslog-protocol])). Other
Standard Development Organizations (e.g. DMTF, TMF) also define
management mechanisms and these mechanisms may be more suitable than
IETF mechanisms in some cases.
Interoperability needs to be considered on the syntactic level and
the semantic level. While it can be irritating and time-consuming,
application designers including operators who write their own scripts
can make their processing conditional to accommodate differences
across vendors or models or releases of product.
Semantic differences are much harder to deal with on the manager side
- once you have the data, its meaning is a function of the managed
entity. For example, if a single counter provided by vendor A counts
three types of error conditions, while the corresponding counter
provided by vendor B counts seven types of error conditions, these
counters cannot be compared effectively - they are not interoperable
counters.
Information models are helpful to try to focus interoperability on
the semantic level - they establish standards for what information
should be gathered, and how gathered information might be used
regardless of which management interface carries the data or which
vendor produces the product. The use of an information model might
help improve the ability of operators to correlate messages in
different protocols where the data overlaps, such as a SYSLOG message
and an SNMP notification about the same event. An information model
might identify which error conditions should be counted separately,
and which error conditions can be counted together in a single
counter. Then, whether the counter is gathered via SNMP or a CLI
command or a SYSLOG message, the counter will have similar meaning.
Protocol designers should consider which information might be useful
for managing the new protocol or protocol extensions.
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IM --> conceptual/abstract model
| for designers and operators
+----------+---------+
| | |
DM DM DM --> concrete/detailed model
for implementers
Information Models and Data Models
Figure 1
On the Difference between Information Models and Data Models
[RFC3444] may be useful in determining what information to consider
regarding information models, as compared to data models.
Information models should come from the protocol WGs and include
lists of events, counters and configuration parameters that are
relevant. There are a number of information models contained in
protocol WG RFCs. Some examples:
o [RFC3060] - Policy Core Information Model version 1
o [RFC3290] - An Informal Management Model for DiffServ Routers
o [RFC3460] - Policy Core Information Model Extensions
o [RFC3585] - IPsec Configuration Policy Information Model
o [RFC3644] - Policy Quality of Service Information Model
o [RFC3670] - Information Model for Describing Network Device QoS
Datapath Mechanisms
o [RFC3805] - Printer MIB v2 (contains both an IM and a DM
Management protocol standards and management data model standards
often contain compliance clauses to ensure interoperability.
Manageability considerations should include discussion of which level
of compliance is expected to be supported for interoperability.
4.2. Management Information
A management information model should include a discussion of what is
manageable, which aspects of the protocol need to be configured, what
types of operations are allowed, what protocol-specific events might
occur, which events can be counted, and for which events should an
operator be notified.
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Operators find it important to be able to make a clear distinction
between configuration data, operational state, and statistics. They
need to determine which parameters were administrative configured and
which parameters have changed since configuration as the result of
mechanisms such as routing protocols.
It is important to be able to separately fetch configuration data,
operational state data, and statistics from devices, and to be able
to compare current state to initial state, and to compare data
between devices.
What is typically difficult to work through are relationships between
abstract objects. Ideally an information model would describe the
relationships between the objects and concepts in the information
model.
Is there always just one instance of this object or can there be
multiple instances? Does this object relate to exactly one other
object or may it relate to multiple? When is it possible to change a
relationship?
Do objects (such as rows in tables) share fate? For example, if a
row in table A must exist before a related row in table B can be
created, what happens to the row in table B if the related row in
table A is deleted? Does the existence of relationships between
objects have an impact on fate sharing?
4.3. Fault Management
The protocol designer should consider how faults information will be
propagated. Will it be done using asynchronous notifications or
polling of health indicators?
If notifications are used to alert operators to certain conditions,
then the protocol designer should discuss mechanisms to throttle
notifications to prevent congestion and duplications of event
notifications. Will there be a hierarchy of faults, and will the
fault reporting be done by each fault in the hierarchy, or will only
the lowest fault be reported and the higher levels be suppressed?
should there be aggregated status indicators based on concatenation
of propagated faults from a given domain or device?
SNMP notifications and SYSLOG messages can alert an operator when an
aspect of the new protocol fails or encounters an error or failure
condition, and SNMP is frequently used as a heartbeat monitor.
Should the event reporting be reliable? [DISCUSS: what is reliable?]
Can we poll the latest events in the box?
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4.3.1. Liveness Detection and Monitoring
Liveness detection and monitoring applies both to the control plane
and the data plane. Mechanisms for detecting faults in the control
plane or for monitoring its liveness are usually built into the
control plane protocols or inherited from underlying data plane or
forwarding plane protocols. These mechanisms do not typically
require additional management capabilities. However, when a system
detects a control plane fault, there is often a requirement to
coordinate recovery action through management applications or at
least to record the fact in an event log. [DISCUSS: can somebody
provide an example?]
Where the protocol is responsible for establishing data or user plane
connectivity, liveness detection and monitoring usually need to be
achieved through other mechanisms. In some cases, these mechanisms
already exist within other protocols responsible for maintaining
lower layer connectivity, but it will often be the case that new
procedures are required to detect failures in the data path and to
report rapidly, allowing remedial action to be taken.
Protocol designers should always build in basic testing features
(e.g. ICMP echo, UDP/TCP echo service, NULL RPC calls) that can be
used to test for liveness, with an option to enable and disable them.
4.3.2. Fault Determination
It can be helpful to describe how faults can be pinpointed using
management information. For example, counters might record instances
of error conditions. Some faults might be able to be pinpointed by
comparing the outputs of one device and the inputs of another device
looking for anomalies.
[DISCUSS: Ralf: While this sounds good, how do you distinguish
between faulty messages and good messages? It might require complex
functions such as deviation from normal, are you sure you want to
implement those at the device level?]
[DISCUSS: Well, deviation from normal is certainly an NMS tasks,
while two neighbor interfaces could exchange simple fault counters in
PERCENTAGES that would give the neighbor a hint about issues. E.g.
if CRC errors are greater than 1% of total traffic both the neighbor
and the NMS could be notified to setup an alternative path/link, if
possible.]
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4.3.3. Fault Isolation
It might be useful to isolate faults, such as a system that emits
malformed messages necessary to coordinate connections properly.
Spanning tree comes to mind. This might be able to be done by
configuring next-hop devices to drop the faulty messages to prevent
them from entering the rest of the network.
4.3.4. Corrective Action
What sort of corrective action can be taken by an operator for each
of the fault conditions that are being identified?
[DISCUSS: this should be expanded or eliminated. If parallel paths
exist between two neighbor devices they could be activated. Not sure
how much further we can take the idea of automated correction
actions.]
[DISCUSS: Somewhere in the fault management section, we should have
pointers to some threshold-based mechanisms, such as RMON events/
alarms or the EVENT-MIB, with the message that we don't need to have
SNMP notifications for all events if we have the right counters that
can be polled as needed.]
4.4. Configuration Management
RFC3139 [RFC3139] discusses requirements for configuration
management. This document includes discussion of different levels of
management, including high-level-policies, network-wide configuration
data, and device-local configuration.
A number of efforts have existed in the IETF to develop policy-based
management. RFC3198 [RFC3198] was written to standardize the
terminology for policy-based management across these efforts.
It is highly desirable that text processing tools such as diff, and
version management tools such as RCS or CVS or SVN, can be used to
process configurations. This approach simplifies comparing the
current operational state to the initial configuration.
With structured text such as XML, simple text diffs may be found to
be inadequate and more sophisticated tools may be needed to make any
useful comparison of versions.
To simplify such configuration comparisons, devices should not
arbitrarily reorder data such as access control lists. If a protocol
designer defines mechanisms for configuration, it would be desirable
to standardize the order of elements for consistency of configuration
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and of reporting across vendors, and across releases from vendors.
[DISCUSS: Ralf: Well, there are two parts to it: 1. An NMS system
could optimize ACLs for performance reasons 2. Unless the device/NMS
systems has correct rules/a lot of experience, reordering ACLs can
lead to a huge security issue, therefore I would rephrase this
paragraph.]
Network wide configurations are ideally stored in central master
databases and transformed into formats that can be pushed to devices,
either by generating sequences of CLI commands or complete
configuration files that are pushed to devices. There is no common
database schema for network configuration, although the models used
by various operators are probably very similar. It is desirable to
extract, document, and standardize the common parts of these network
wide configuration database schemas. A protocol designer should
consider how to standardize the common parts of configuring the new
protocol, while recognizing the vendors will likely have proprietary
aspects of their configurations.
It is important to distinguish between the distribution of
configurations and the activation of a certain configuration.
Devices should be able to hold multiple configurations. NETCONF
[RFC4741], for example, differentiates between the "running"
configuration and "candidate" configurations.
[DISCUSS: Also add: backup configurations, i.e. version n-1 and auto-
fallback solutions that automatically return to the previous known
good configuration or adding a backdoor for the operator. One of the
worst scenarios is remote device configuration where the new running
configuration does not work as expected and unlocks the admin.
Vendors may have ways to avoid unlocking the operator but this does
not have to be vendor specific.]
[DISCUSS: 1. Describe the concept of a "Gold config" and updating it
frequently 2. Describe a "backdoor" undo strategy ]
It is important to enable operators to concentrate on the
configuration of the network as a whole rather than individual
devices. Support for configuration transactions across a number of
devices would significantly simplify network configuration
management. The ability to distribute configurations to multiple
devices, or modify "candidate configurations on multiple devices, and
then activate them in a near-simultaneous manner might help.
[DISCUSS: Ralf: This might be a good place for adding the description
of configuration-templates.]
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Consensus of the 2002 IAB Workshop was that textual configuration
files should be able to contain international characters. Human-
readable strings should utilize UTF-8, and protocol elements should
be in case insensitive ASCII.
A mechanism to dump and restore configurations is a primitive
operation needed by operators. Standards for pulling and pushing
configurations from/to devices are desirable.
Given configuration A and configuration B, it should be possible to
generate the operations necessary to get from A to B with minimal
state changes and effects on network and systems. It is important to
minimize the impact caused by configuration changes.
Many protocol specifications include timers that are used as part of
operation of the protocol. These timers may need default values
suggested in the protocol specification and do not need to be
otherwise configurable. [DISCUSS: mention NTP?]
4.4.1. Verifying Correct Operation
An important function that should be provided is a tool set for
verifying the correct operation of a protocol. This may be achieved
to some extent through access to information and data models that
report the status of the protocol and the state installed on network
devices. It may also be valuable to provide techniques for testing
the effect that the protocol has had on the network by sending data
through the network and observing its behavior. [DISCUSS: Before
deploying? Before operating? How to achieve this?]
Protocol designers should consider how to test the correct end-to-end
operation of the network, and how to verify the correct data or
forwarding plane function of each network element.
4.4.2. Control of Function and Policy
A protocol designer should consider the configurable items that exist
for the control of function via the protocol elements described in
the protocol specification. For example, Sometimes the protocol
requires that timers can be configured by the operator to ensure
specific policy-based behavior by the implementation.
4.5. Accounting Management
A protocol designer should consider whether it would be appropriate
to collect usage information related to this protocol, and if so,
what usage information would be appropriate to collect?
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RFC2975 [RFC2975] Introduction to Accounting Management discusses a
number of factors relevant to monitoring usage of protocols for
purposes of capacity and trend analysis, cost allocation, auditing,
and billing. This document also discusses how RADIUS [RFC2865],
TACACS+ [RFC1492], SNMP, IPFIX, and PSAMP protocols can be used for
these purposes. These factors should be considered when designing a
protocol whose usage might need to be monitored, or when recommending
a protocol to do usage accounting.
4.6. Performance Management
Consider information that would be useful when trying to determine
the performance characteristics of a deployed system using the target
protocol.
What are the principal performance factors that need to be looked at
when measuring the operational performance of the protocol
implementations? Is it important to measure setup times? throughput?
quality versus throughput? interruptions? end-to-end throughput? end-
to-end quality? hop-to-hop throughput?
Consider scalability, such as whether performance will be affected by
the number of protocol connections. If so, then it might be useful
to provide information about the maximum number of table entries that
should be expected to be modeled, how many entries an implementation
can support, the current number of instances, and the expected
behavior when the current instances exceed the capacity of the
implementation. This should be considered in a data-modeling
independent manner - what makes managed-protocol sense, not what
makes management-protocol-sense. If it is not managed-protocol-
dependent, then it should be left for the management-protocol data
modelers to decide. For example, VLAN identifiers have a range of
1..4095 because of the VLAN standards. A MIB implementing a VLAN
table should be able to support 4096 entries because the content
being modeled requires it.
Consider operational activity, such as the number of message in and
the messages out, the number of received messages rejected due to
format problems, the expected behaviors when a malformed message is
received.
Consider the expected behaviors for counters - what is a reasonable
maximum value for expected usage? should they stop counting at the
maximum value and retain the maximum value, or should they rollover?
How can users determine if a rollover has occurred, and how can users
determine if more than one rollover has occurred?
What information should be maintained across reboots of the device,
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or restarts of the management system?
Could events, such as hot-swapping a blade in a chassis, cause
discontinuities in information? Does this make any difference in
evaluating the performance of a protocol?
Consider whether multiple management applications will share a
counter; if so, then no one management application should be allowed
to reset the value to zero since this will impact other applications.
For performance monitoring, it is often important to report the time
spent in a state rather than the current state. Snapshots are of
less value for performance monitoring. [DISCUSS: please elaborate]
The Benchmarking Methodology WG (bmwg) has defined recommendations
for the measurement of the performance characteristics of various
internetworking technologies in a laboratory environment, including
the systems or services that are built from these technologies. Each
recommendation describes the class of equipment, system, or service
being addressed; discuss the performance characteristics that are
pertinent to that class; clearly identify a set of metrics that aid
in the description of those characteristics; specify the
methodologies required to collect said metrics; and lastly, present
the requirements for the common, unambiguous reporting of
benchmarking results.
[DISCUSS: there are several parts to performance management. Device
monitoring (with the impact of the new protocol/service activation),
protocol monitoring, and services monitoring. This section might
benefit from being broken into different pieces.]
4.7. Security Management
Protocol designers should consider how to monitor and to manage
security aspects and vulnerabilities of the new protocol.
There will be security considerations related to the new protocol.
To make it possible for operators to be aware of security-related
events, it is recommended that system logs should record events, such
as failed logins, but the logs must be secured.
Should a system automatically notify operators of every event
occurrence, or should an operator-defined threshold control when a
notification is sent to an operator?
Should certain statistics be collected about the operation of the new
protocol that might be useful for detecting attacks, such as the
receipt of malformed messages, or messages out of order, or messages
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with invalid timestamps? If such statistics are collected, is it
important to count them separately for each sender to help identify
the source of attacks?
Manageability considerations that are security-oriented might include
discussion of the security implications when no monitoring is in
place, the regulatory implications of absence of audit-trail or logs
in enterprises, exceeding the capacity of logs, and security
exposures present in chosen / recommended management mechanisms.
The granularity of access control needed on management interfaces
needs to match operational needs. Typical requirements are a role-
based access control model and the principle of least privilege,
where a user can be given only the minimum access necessary to
perform a required task.
It must be possible to do consistency checks of access control lists
across devices. Protocol designers should consider information
models to promote comparisons across devices and across vendors to
permit checking the consistency of security configurations.
Protocol designers should consider how to provide a secure transport,
authentication, identity, and access control which integrates well
with existing key and credential management infrastructure. It is a
good idea to start with defining the threat model for the protocol,
and from that deducing what is required.
Protocol designers should consider how access control lists are
maintained and updated.
Standard SNMP notifications or SYSLOG messages
[I-D.ietf-syslog-protocol] might already exist, or can be defined, to
alert operators to the conditions identified in the security
considerations for the new protocol. [DISCUSS: can somebody provide
an example of an existing notifications or syslog messages related to
security, other than SNMPv3-specific notifications?]
An analysis of existing counters might help operators recognize the
conditions identified in the security considerations for the new
protocol before they can impact the network.
RADIUS and DIAMETER can provide authentication and authorization. A
protocol designer should consider which attributes would be
appropriate for their protocol.
Different protocols use different assumptions about message security
and data access controls. A protocol designer that recommends using
different protocols should consider how security will be applied in a
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balanced manner across multiple management interfaces. SNMP access
control is data-oriented, while CLI access control is usually command
(task) oriented. Depending on the management function, sometimes
data-oriented or task-oriented access control makes more sense.
Protocol designers should consider both data-oriented and task-
oriented access control.
5. Documentation Guidelines
The purpose of this document is to provide guidance about what to
consider when thinking about the management and deployment of a new
protocol, and to provide guidance about documenting the
considerations. The following guidelines are designed to help
writers provide a reasonably consistent format for such
documentation. Separate manageability and operational considerations
sections are desirable in many cases, but their structure and
location is a decision that can be made from case to case.
We want to avoid seeming to impose a solution by putting in place a
strict terminology - for example implying that a formal data model,
or even using a management protocol is mandatory. If protocol
designers conclude that its technology can be managed solely by using
proprietary CLIs, and no structured or standardized data model needs
to be in place, this might be fine, but it is a decision that should
be explicit in a manageability discussion, that this is how the
protocol will need to be operated and managed. Protocol designers
should avoid having manageability pushed for a later/never phase of
the development of the standard.
Making a Management Considerations section a mandatory publication
requirement for IETF documents is the responsibility of the IESG, or
specific area directors, or working groups, and this document avoids
recommending any mandatory publication requirements. For a complex
protocol, a completely separate draft on operations and management
might be appropriate, or even a completely separate WG effort.
This document is focused on what to think about, and how to document
the considerations of the protocol designer.
5.1. Recommended Discussions
A Manageability Considerations section should include discussion of
the management and operations topics raised in this document, and
when one or more of these topics is not relevant, it would be useful
to contain a simple statement explaining why the topic is not
relevant for the new protocol. Of course, additional relevant topics
should be included as well.
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Existing protocols and data models can provide the management
functions identified in the previous section. Protocol designers
should consider how using existing protocols and data models might
impact network operations.
5.2. Null Manageability Considerations Sections
A protocol designer may seriously consider the manageability
requirements of a new protocol, and determine that no management
functionality is needed by the new protocol. It would be helpful to
those who may update or write extensions to the protocol in the
future or to those deploying the new protocol to know the thinking of
the working regarding the manageability of the protocol at the time
of its design.
If there are no new manageability or deployment considerations, it is
recommended that a Manageability Considerations section contain a
simple statement such as "There are no new manageability requirements
introduced by this document," and a brief explanation of why that is
the case. The presence of such a Manageability Considerations
section would indicate to the reader that due consideration has been
given to manageability and operations.
In the case where the new protocol is an extension, and the base
protocol discusses all the relevant operational and manageability
considerations, it would be helpful to point out the considerations
section in the base document.
5.3. Placement of Operations and Manageability Considerations Sections
If a protocol designer develops a Manageability Considerations
section for a new protocol, it is recommended that the section be
placed immediately before the Security Considerations section.
Reviewers interested in such sections could find it easily, and this
placement could simplify the development of tools to detect the
presence of such a section.
6. IANA Considerations
This document does not introduce any new codepoints or name spaces
for registration with IANA. Note to RFC Editor: this section may be
removed on publication as an RFC.
7. Security Considerations
This document is informational and provides guidelines for
considering manageability and operations. It introduces no new
security concerns.
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8. Acknowledgements
This document started from an earlier document edited by Adrian
Farrel, which itself was based on work exploring the need for
Manageability Considerations sections in all Internet-Drafts produced
within the Routing Area of the IETF. That earlier work was produced
by Avri Doria, Loa Andersson, and Adrian Farrel, with valuable
feedback provided by Pekka Savola and Bert Wijnen.
Some of the discussion about designing for manageability came from
private discussions between Dan Romascanu, Bert Wijnen, Juergen
Schoenwaelder, Andy Bierman, and David Harrington.
9. Informative References
[I-D.ietf-syslog-protocol] Gerhards, R., "The syslog Protocol",
draft-ietf-syslog-protocol-23 (work in
progress), September 2007.
[RFC1034] Mockapetris, P., "Domain names - concepts
and facilities", STD 13, RFC 1034,
November 1987.
[RFC1052] Cerf, V., "IAB recommendations for the
development of Internet network
management standards", RFC 1052,
April 1988.
[RFC1492] Finseth, C., "An Access Control Protocol,
Sometimes Called TACACS", RFC 1492,
July 1993.
[RFC2119] Bradner, S., "Key words for use in RFCs
to Indicate Requirement Levels", BCP 14,
RFC 2119, March 1997.
[RFC2205] Braden, B., Zhang, L., Berson, S.,
Herzog, S., and S. Jamin, "Resource
ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205,
September 1997.
[RFC2439] Villamizar, C., Chandra, R., and R.
Govindan, "BGP Route Flap Damping",
RFC 2439, November 1998.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed.,
and J. Schoenwaelder, Ed., "Structure of
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Management Information Version 2
(SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2821] Klensin, J., "Simple Mail Transfer
Protocol", RFC 2821, April 2001.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The
Interfaces Group MIB", RFC 2863,
June 2000.
[RFC2865] Rigney, C., Willens, S., Rubens, A., and
W. Simpson, "Remote Authentication Dial
In User Service (RADIUS)", RFC 2865,
June 2000.
[RFC2975] Aboba, B., Arkko, J., and D. Harrington,
"Introduction to Accounting Management",
RFC 2975, October 2000.
[RFC3060] Moore, B., Ellesson, E., Strassner, J.,
and A. Westerinen, "Policy Core
Information Model -- Version 1
Specification", RFC 3060, February 2001.
[RFC3084] Chan, K., Seligson, J., Durham, D., Gai,
S., McCloghrie, K., Herzog, S.,
Reichmeyer, F., Yavatkar, R., and A.
Smith, "COPS Usage for Policy
Provisioning (COPS-PR)", RFC 3084,
March 2001.
[RFC3139] Sanchez, L., McCloghrie, K., and J.
Saperia, "Requirements for Configuration
Management of IP-based Networks",
RFC 3139, June 2001.
[RFC3198] Westerinen, A., Schnizlein, J.,
Strassner, J., Scherling, M., Quinn, B.,
Herzog, S., Huynh, A., Carlson, M.,
Perry, J., and S. Waldbusser,
"Terminology for Policy-Based
Management", RFC 3198, November 2001.
[RFC3290] Bernet, Y., Blake, S., Grossman, D., and
A. Smith, "An Informal Management Model
for Diffserv Routers", RFC 3290,
May 2002.
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[RFC3410] Case, J., Mundy, R., Partain, D., and B.
Stewart, "Introduction and Applicability
Statements for Internet-Standard
Management Framework", RFC 3410,
December 2002.
[RFC3444] Pras, A. and J. Schoenwaelder, "On the
Difference between Information Models and
Data Models", RFC 3444, January 2003.
[RFC3460] Moore, B., "Policy Core Information Model
(PCIM) Extensions", RFC 3460,
January 2003.
[RFC3535] Schoenwaelder, J., "Overview of the 2002
IAB Network Management Workshop",
RFC 3535, May 2003.
[RFC3585] Jason, J., Rafalow, L., and E. Vyncke,
"IPsec Configuration Policy Information
Model", RFC 3585, August 2003.
[RFC3644] Snir, Y., Ramberg, Y., Strassner, J.,
Cohen, R., and B. Moore, "Policy Quality
of Service (QoS) Information Model",
RFC 3644, November 2003.
[RFC3670] Moore, B., Durham, D., Strassner, J.,
Westerinen, A., and W. Weiss,
"Information Model for Describing Network
Device QoS Datapath Mechanisms",
RFC 3670, January 2004.
[RFC3805] Bergman, R., Lewis, H., and I. McDonald,
"Printer MIB v2", RFC 3805, June 2004.
[RFC4741] Enns, R., "NETCONF Configuration
Protocol", RFC 4741, December 2006.
[RFC5105] Lendl, O., "ENUM Validation Token Format
Definition", RFC 5105, December 2007.
Appendix A. Review Checklist
This appendix provides a quick summary of issues to consider.
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A.1. General Document Checklist
Is the document readable?
Does it contain nits?
Is the document class appropriate?
Is the problem well stated?
Is the problem really a problem?
Does the document consider existing solutions?
Does the solution break existing technology?
Does the solution preclude future activity?
Is the specification complete? Can multiple interoperable
implementations be built based on the specification?
A.2. Operations and Management Checklist
Is the proposed specification deployable? If not, how could it be
improved? Does the document include a description of the
operational model - how is this protocol or technology going to be
deployed and managed? will it use centralized or distributed
management? will it require remote and/or local management
applications?
Is the solution sufficiently configurable? are configuration
parameters clearly identified? are configuration parameters
normalized? does each configuration parameter have a reasonable
default value? Will configuration be pushed to a device by a
configuration manager, or pulled by a device from a configuration
server? How will the devices and managers find and authenticate
each other?
Does the solution have failure modes that are difficult to
diagnose or correct? Are faults and alarms reported and logged?
is protocol state information exposed to the user? How? are
significant state transitions logged?
Does the protocol have an impact on network traffic and network
devices? is protocol performance information exposed to the user?
Can performance be measured? Does the solution scale well? Does
the proposed approach have any scaling issues that could affect
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usability for large scale operation?
Are there any backward compatibility issues?
Do you anticipate any manageability issues with the specification?
Does the specification introduce new potential security risks or
avenues for fraud?
Does the proposed protocol have a significant operational impact
on the Internet. If it does, and the document under review
targets standards track, is their enough proof of implementation
and/or operational experience to grant Proposed Standard status?
Appendix B. Open Issues
Identify bullets for appendix checklist
align checklist order and guidelines order
Is section 2 needed? it seems too management-centric.
Need more reviews and suggested text, especially on operational
considerations
[DISCUSS: How much of RFC 3535 and RFC 3139 should be repeated
(and updated) in these guidelines? There are many best current
practices mentioned in those documents. Should we bring them
together into this document and expand on how they should
influence ops/mgmt considerations for a new protocol? Many of the
points relate to NM protocol design, but there are also many
points about operational and management considerations.]
Appendix C. DISCUSSES that have yet to be discussed
All of these discusses have been copied from the text. They all need
discussion and proposed text before the editor will know what needs
to be put into the document.
[DISCUSS: examples, list of current protocols characteristics and
their impact on the network. e.g., burst traffic impact on network
congestion.]
[DISCUSS: would the example of inconsistency between MIB counters
that cannot be reset and CLI counters that can be rest be useful
here?]
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[DISCUSS: this could use a good example of when a protocol
designer should consider future extensions to the management. Are
we talking about writing extensible data models? ]
[DISCUSS: is this paragraph really about protocol design for
operability or about operational practice? If this stays, it
probably needs a bit more discussion on database driven
configurations, and how protocol design would be impacted by the
expectation of database-driven configuration. ]
[DISCUSS: this needs rewording to better describe consistency
checking 1) over time, and 2) between ends of a link. probably
needs a bit more discussion on the need to be able to understand
and check what it is happening on the wire actually matches what
the Operator tried to configure. Basically, complexity is your
enemy here, and that cannot be stressed often enough (no idea how
you can verify whether for example a SIP application is actually
doing what it is supposed to do due to the complexity).]
[DISCUSS: Is a section on P2P vs. central management called for
here?]
[DISCUSS: what is reliable?]
[DISCUSS: can somebody provide an example?]
[DISCUSS: Ralf: While this sounds good, how do you distinguish
between faulty messages and good messages? It might require
complex functions such as deviation from normal, are you sure you
want to implement those at the device level?]
[DISCUSS: Well, deviation from normal is certainly an NMS tasks,
while two neighbor interfaces could exchange simple fault counters
in PERCENTAGES that would give the neighbor a hint about issues.
E.g. if CRC errors are greater than 1% of total traffic both the
neighbor and the NMS could be notified to setup an alternative
path/link, if possible.]
[DISCUSS: this should be expanded or eliminated. If parallel
paths exist between two neighbor devices they could be activated.
Not sure how much further we can take the idea of automated
correction actions.]
[DISCUSS: Somewhere in the fault management section, we should
have pinters to some threshold-based mechanisms, such as RMON
events/alarms or the EVENT-MIB, with the message that we don't
need to have SNMP notifications for all events if we have the
right counters that can be polled as needed.]
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[DISCUSS: Ralf: Well, there are two parts to it: 1. An NMS system
could optimize ACLs for performance reasons 2. Unless the device/
NMS systems has correct rules/a lot of experience, reordering ACLs
can lead to a huge security issue, therefore I would rephrase this
paragraph.]
[DISCUSS: Also add: backup configurations, i.e. version n-1 and
auto-fallback solutions that automatically return to the previous
known good configuration or adding a backdoor for the operator.
One of the worst scenarios is remote device configuration where
the new running configuration does not work as expected and
unlocks the admin. Vendors may have ways to avoid unlocking the
operator but this does not have to be vendor specific.]
[DISCUSS: 1. Describe the concept of a "Gold config" and updating
it frequently 2. Describe a "backdoor" undo strategy ]
[DISCUSS: Ralf: This might be a good place for adding the
description of configuration-templates.]
[DISCUSS: mention NTP?]
[DISCUSS: Before deploying? Before operating? How to achieve
this?]
[DISCUSS: please elaborate]
[DISCUSS: there are several parts to performance management.
Device monitoring (with the impact of the new protocol/service
activation), protocol monitoring, and services monitoring. This
section might benefit from being broken into different pieces.]
[DISCUSS: can somebody provide an example of an existing
notifications or syslog messages related to security, other than
SNMPv3-specific notifications?]
[DISCUSS: How much of RFC 3535 and RFC 3139 should be repeated
(and updated) in these guidelines? There are many best current
practices mentioned in those documents. Should we bring them
together into this document and expand on how they should
influence ops/mgmt considerations for a new protocol? Many of the
points relate to NM protocol design, but there are also many
points about operational and management considerations.]
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Appendix D. Change Log
Changes from opsawg-02 to opsawg-03
From reviews by Lixia Zhang and feedback from WG Chairs' Lunch.
added discussion of impact on the Internet to checklist
spell check
added examples
added discussion of default values
added discussion of database-driven configuration
fixed some references
expanded the checklist
Changes from opsawg-01 to opsawg-02
moved survey of protocols and data models to separate document
changed "working group" to "protocol designer" throughout, as
applicable.
modified wording from negative to positive spin in places.
updated based on comments from Ralf Wolter and David Kessens
Changes from opsawg-00 to opsawg-01
moved Proposed Standard data models to appendix
moved advice out of data model survey and into considerations
section
addressed comments from Adrian and Dan
modified the Introduction and Section 2 in response to many
comments.
expanded radius and syslog discussion, added psamp and VCCV,
modified ipfix,
Changes from harrington-01 to opsawg-00
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added text regarding operational models to be managed.
Added checklist appendix (to be filled in after consensus is
reached on main text )
Changes from harrington-00 to harrington-01
modified unclear text in "Design for Operations and Management"
Expanded discussion of counters
Removed some redundant text
Added ACLs to Security Management
Expanded discussion of the status of COPS-PR, SPPI, and PIBs.
Expanded comparison of RADIUS and Diameter.
Added placeholders for EPP and XCAP protocols.
Added Change Log and Open Issues
Author's Address
David Harrington
Huawei Technologies USA
1700 Alma Dr, Suite 100
Plano, TX 75075
USA
Phone: +1 603 436 8634
Fax:
EMail: dharrington@huawei.com
URI:
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