Network Management
What it is and what it isn't.
By Douglas W. Stevenson
douglas.stevenson@predictive.com
Apr 1995
Table of Contents
- Introduction
- Functional Architecture
- Defining the Pieces
- Managed Objects
- Element Management Systems (EMS's)
- Manager of Managers Systems (MoM's)
- User Interface
- Management Functional Areas (MFAs)
- Fault Management
- Configuration Management
- Accounting
- Performance Management
- Security
- Common Implementations
- Management Focus
- The Right Implementation
- Business Case Requirements
- Definition
- System Focus
- Reporting of Trend Analysis
- Alarm Correlation
- Trouble Ticket Integration
- What Happens Now that I've Received an Alarm?
- Systems Automation
- Enabling Communications
- Building the Perfect Beast
- Management Functional Domains (MFD's)
- Building Requirements
- Questions to Ask
- Conclusion
Network Management as a term has many definitions dependent on whose
operational function is in question. It is the goal of this paper to
illustrate and discuss today's most common implementations of Network
management systems as they apply to actual MIS form and function and
illustrate a What's wrong with this picture type of scenario. Then
discuss what the ideal system will look like.
Network management systems have been in operation many years especially in
their own proprietary worlds such as Netview, AT&T Accumaster and Digital
Equipment Corporation's DMA. With the implementation of SNMP, local area
and wide area network components could be monitored and "managed". With
the vast amount of raw data available, most MIS Managers have no idea what
they really want because, in part, they don't know what's available.
Additionally, how does the data get into a format that actually means
something? Other communications systems are considered non-manageable
because they are only accessible by an RS-232 port and not by Netview or
SNMP. Others tend to believe that Network Management means nothing but the
monitoring and management of network architectural hardware such as
Routers, bridges and concentrators -- nothing above the network layer of
the OSI model is considered manageable.
What's alarming is that most Senior Network Engineers tend to be resigned
to spend thousands of dollars on hardware and software BEFORE the real
requirements are gathered and defined. Consequently, MIS departments either
spend very little on network management or they "go for broke" with the
huge hardware platforms and expensive artificial intelligence engines
driving network management for the company.
In today's environment of cost cutting and productivity enhancements, most
common network management implementations increase the number of people
required to support the MIS functions and these new people are senior level
engineering and support types; very expensive in most cases. Typical
costs extend into the hundreds of thousands of dollars purchasing hardware
and software not to mention the additional personnel.
Network management systems have to be geared toward the work flow of the
organization in which they will be utilized. As each MIS implementation is
geared toward the business requirements, so should the network management
system. If the management functionality does not directly or indirectly
solve a business problem, it is totally useless to the overall MIS
department and to the company.
Network management doesn't mean one application with a database with some
huge chunk of iron running the show. It is really an integrated
conglomeration of functions that may be on one machine but may span
thousands of miles, different support organizations and many machines and
databases. It is these functions that must be directly driven by the
business case for each.
Network management systems have four basic levels of functionality. Each
level has a set of tasks defined to provide, format, or collect data
necessary to manage the objects. Figure 1 illustrates these four levels of
functionality.
Figure 1
Managed Objects are the devices, systems and/or anything else requiring
some form of monitoring and management. Most implementations leave out the
"anything else" clause because they usually don't have the business case
requirements before the design, therefore they design as they go.
Some examples of managed objects include routers, concentrators, hosts,
servers and applications like Oracle, Microsoft SMS, Lotus Notes, and MS
Mail. The managed object does not have to be a piece of hardware but
should rather be depicted as a function provided on the network.
An EMS manages a specific portion of the network. For example SunNet
Manager, an SNMP management application, is used to manage SNMP manageable
elements. Element Managers may manage async lines, multiplexers, PABX's,
proprietary systems or an application.
MoM systems integrate together the information associated with several
element management systems, usually performing alarm correlation between
EMS's. There are several different products that fall into this category
to include Boole & Babbage's CommandPost, NyNEX AllLink, International
Telematics MAXM, OSI NetExpert and others.
The actual data to be collected comes from the managed object, in most
cases. This data is collected by the EMS systems which in turn
consolidates the data in a database for processing and retrieval.
The user interface to the information, whether real time alarms and alerts
or trend analysis graphs and reports, is the principal piece to deploying a
successful system. If the information gathered cannot be distributed to
the whole MIS organization to keep people informed and to enable team
communications, the real purpose of a Network Management system is lost in
the implementation. Data doesn't mean anything if it is not used to
make informed decisions about the optimization of systems and functions.
These systems components are, in turn, mapped back to what is called
Management Functional Areas (MFAs). These MFAs are the wish list of which
areas in which management applications as a system focus their attention.
The most common framework depicted in Network management designs is
centered around the Open Systems Interconnect (OSI) "FCAPS" model of MFAs.
However most network management implementations do not really cover all of
these areas. Other areas that may be important to the MIS function and to
specific business units within the company may not be addressed at all.
FCAPS is an acronym explained as follows:
Fault Management
Configuration Management
Accounting
Performance Management
Security Management
Some of the other areas covered under Management Functional Areas include:
Chargeback
Systems Management
Cost Management
Fault management is the detection of a problem, fault isolation and
correction to normal operation. Most systems poll the managed objects
search for error conditions and illustrate the problem in either a graphic
format or a textual message. Most of these types of messages are setup by
the person configuring the polling on the Element Management System. Some
Element Management Systems collect data directly from a log printer type
output receiving the alarm as it occurs.
Fault management deals most commonly with events and traps as they occur on
the network. Keep in mind though, that using data reporting mechanisms to
report alarms or alerts is the best way to accomplish health checks of
specific managed object's performance without having to double the amount
of polling being accomplished.
Configuration management is probably, the most important part of network
management in that you cannot accurately manage a network unless you can
manage the configuration of the network. Changes, additions and deletions
from the network need to be coordinated with the network management systems
personnel. Dynamic updating of the configuration needs to be accomplished
periodically to ensure the configuration is known.
The accounting function is usually left out of most implementations in that
LAN based systems are said to not promote accounting type functions until
one gets into the Hosts such as IBM Mainframe or Digital VAX's. Others
rationalize the accounting is a server specific function and should be
managed by the System administrators.
Performance is a key concern to most MIS support people. Although, it is
high on the list, it is considered difficult to be factual about some LAN
performance issues unless employing RMON technology. (This is one of those
examples of throwing money at a problem.) Although RMON Pods are very
useful, one should carefully weigh what's pertinent to what can be
accomplished in other ways without having to spend a bundle.
Performance of Wide Area Network (WAN) links, telephone trunk utilization,
etc., are areas that must be revisited on a continuing basis as these are
some of the areas easiest to optimize and realize savings.
Systems or applications performance is another area in which optimization
can be accomplished but most network management applications don't address
this in a functional manner.
Most network management applications only address security applicable to
network hardware such as someone logging into a router or bridge. Some
network management systems have alarm detection and reporting capabilities
as part of physical security (contact closure, fire alarm interface, etc.)
None really deal with system security as this is a function of System
administration (or so you thought!).
- Chargeback
-
Chargeback has been done for years in the large mainframe environments and
will continue to be accomplished as it is a way to charge the end user for
only the specific portion of the service that he or she uses. Chargeback
on Local Area Networks presents new challenges in that so many services are
provided. In many implementations, chargeback is accomplished on the
individual Server providing the service. While chargeback is very
difficult on broadcast based networks such as Ethernet, it is realizable on
networks that dynamically allocate bandwidth as the end users' needs
dictate (ATM). As technology associated with monitoring LAN and WAN
networks evolves, chargeback will be integrated into more and more
systems.
- Systems Management
-
Systems Management is the management and administration of services
provided on the network. A lot of implementations leave out this very
crucial part in that this is one of the areas in which Network Management
systems can show significant capabilities, streamline business processes,
and save the customer money with just a little work. There are many good
COTS products available to automate system administration functions and
these products can be easily integrated into the overall Network Management
system very easily.
- Cost Management
-
Cost management is an avenue in which the reliability, operability and
maintainability of managed objects are addressed. This one function is an
enabler to upgrade equipment, delete unused services and tune the
functionality of the Servers to the services provided. By continuously
addressing the cost of maintenance, Mean Time Between Failure (MTBF), and
Mean Time To Repair (MTTR) statistics, costs associated with maintaining
the network as a system can be tuned. This area is an MFA that is driven
by I/T management to address getting the most performance from the money
allocated.
Most implementations of medium and large network management systems center
around a Network Management Center of some sort. From this location, all
data is sent and processed. While several EMS's are used to manage their
specific areas, all of the data comes back to the Manager of Managers
application. Most fault detection, isolation and troubleshooting is
accomplished in the Network Management Center and technicians dispatched
when the problem has been analyzed as far as possible. Several company
locations may be involved in the overall network spanning thousands of
miles and around the globe.
Figure 2
The management focus for this scenario is on the Network Management Center
driving the total operation. Detection, troubleshooting and dispatching is
accomplished from the NMC. This operational focus is a carry over from the
old Netview days in that the center of the picture was a huge IBM Mainframe
that did all of the work. If you don't have a Network Management Center
today, consider what it will cost not only for the hardware and software,
but the people to accomplish this and their level of expertise.
If you, as an MIS Manager, are looking at the benefits of network
management to reduce downtime and overall cost to your program, make sure
that the business case requirements drive the implementation and not the
implementation drive the business cases.
As a systems integrator, make sure the requirements are accomplished before
any implementation. When the requirements are put in place, it is your job
as an Engineer to make sure management is informed as to what each
implementation segment will cost along with what that capability brings to
the overall MIS function.
In today's world, any implementation must follow the business case
associated with what will be implemented. The implementation must solve a
business problem or increase efficiency of the current methods of
accomplishing work while reducing overall costs. If the solution doesn't
save money while providing a better service, it probably isn't worth
accomplishing.
The hardest part of building a business case is the gathering of the
information. One must define the problem at hand in a general sense so
that you can look for specific problems network management can address in
that area.
The developer of the business case must look at the current way each section accomplishes its day to day work. The case for network management can be definitized by documenting current work processes that may be automated by the system as a whole. Each of the work processes to be automated need to be documented and addressed in the system design and implementation.
Look for ways to save the organization money. Keep addressing getting the MIS organization and the services they provide, more efficient.
Levels of Activity
There are four levels of activity that one must understand before applying
management to a specific service or device. These four levels of activity
are as follows:
- Inactive
-
This is the case when no monitoring is being done and if you did receive an
alarm in this area, you would ignore it.
- Reactive
-
This is where you react to a problem after it has occurred yet no monitoring
has been applied.
- Interactive
-
This is where you are monitoring components but must interactively
troubleshoot to eliminate the side effect alarms and isolate to a root cause.
- Proactive
-
This is where you are monitoring components and the system provides a root
cause alarm for the problem at hand and automatic restoral processes are in
place where possible to minimize downtime.
These four levels of activities outline exactly how your support
organization is dealing with problems today and where you, as an MIS
manager want them to be in terms of goals. Within the support organization
are teams with different goals and focuses (i.e. Unix support, desktop
support, network support, etc.). Keep in mind that while a specific alarm
may warrant an inactive approach by one team, to another team it may demand
a proactive approach. Keep these goals in mind when gathering requirements
for network management.
Today's Implementations
Of the network management implementations done today, very few really
address the needs of the business. Most are implemented with good
intentions but are focused away from increasing efficiency.
In a multiple site network, there are technicians, engineers and support
personnel at each major location as required. No one knows those local
environments better than the people having to do the work. No one knows
the people of the organization better than the Help Desk staff as they are
the first line of communication between the people and the MIS support
organization.
Network management elements are considered, among other things, tools in
which troubleshooting can be accomplished. The local support staff could
benefit greatly from the use of these systems as a tool. As such, most
implementations give read-only access to these systems. The ability to
focus these tools at a local level is paramount to increasing the
effectiveness to the local support staff. In some implementations, where
read/write access is provided, it is accomplished through X-Windows which
doesn't work very well across low speed links.
Most implementations focus these tools at a global level in that they are
located in the Network Command Center. When a trouble ticket is generated
from the NCC, it reflects a problem or symptom generated by the network
management elements and/or the Manager of Managers. Sometimes, the local
technician can not relate to this symptom because he or she doesn't
understand where this message came from or why. Without access to the
management element and familiarity with the product, they usually start off
problem isolation in a "cloud" looking for the problem.
When a global problem occurs, in these scenarios, the information is
concentrated and orchestrated by the Network Command Center. Additionally
an outage can black out management of a geographic location by centralizing
the management resources. Figure 3 illustrates how this occurs.
Figure 3
As far as the Network Management Center is concerned, all of the devices
beyond the point of breakage are down. In fact, without alarm correlation,
all of the devices will be depicted as bad. Even with alarm correlation,
it can only be accomplished on one side of the link. No network management
capabilities exist at the remote site to help troubleshoot the problem.
The ideal network management system should be designed and implemented
around the real work processes. It should focus the tools toward those
staff members supporting the managed area in a manner which makes their job
easier and faster. Information associated with a problem or symptom should
mean something to the support personnel. If they see the problem at a
glance, they should know which specific area that problem belongs and what
to do to get started in the trouble isolation process. Other personnel in
the organization should know that a specific technician is looking into the
problem as the problem may be affecting other areas.
Help Desk personnel should know what is happening and who is working on
what at a glance. If they are not familiar with the system in question,
they should have adequate information at their fingertips to guide them in
what to do, who to call, and what steps to take, even what questions to
ask.
Additionally, the problems that affect other sites, should be available to
those personnel at a glance. The information must be at the fingertips of
the other sites' Help Desk personnel so that they know, in near real time,
what is going on.
See how the focus of information should be; local when it is a local
problem and global when it is a global problem. Also, the tools associated
are more focused on the local situation and not the global picture.
Figure 4 depicts a more distributed system providing global information
with local focus. In this system, alarms can be passed from site to site
and even around a problem with simple client-server database techniques.
Figure 4
In the scenario in figure 4, if a link breaks, local tools and alarms are
still available. Alarms concerning the overall health of other links and
connectivity can be passed to other sites, even around a problem. Using a
SLIP or PPP dial up link between management elements can be used to pass
critical data about a link outage in near real time.
Network management across low speed wide area links doesn't really make
sense. Bandwidth of this type is costly compared to LAN bandwidth in that
there are the monthly charges for the links. Consider also that most WAN
links are interconnected by bridges or routers. On the back side of these
devices are networks capable of 10 Mbps, 16 Mbps or even 100 Mbps. On the
link side you see 1.544 Mbps, 512kbps or even 19.2kbps links. Actual
polling of network management elements (SNMP) could consume these links
drastically reducing the operational capabilities of the link. The
question to ask is Do you want to increase the bandwidth across these
links just for network management or do you want to distribute the
management polling to local area concentrations and just pass the real
alarm information?
Trend analysis is usually a local function as one is looking for growth
rates on local hardware, applications and systems. Only when the Wide Area
Network is trended does the information require analysis between multiple
sites. Even then, local or remote changes can affect each others'
environment.
The personnel that should be accomplishing the trending are the people
actually accomplishing the work; again no one knows the environment better
than those personnel. Reporting needs to be accomplished on an as needed
basis because each report needs to be in a format the local support
personnel can understand. Therefore, calculations must be available to
simplify data in the reports including averages, percentages and
comparisons. Each type of report needs to be customizable and easy to
change.
Specific areas of reporting are very useful in looking at the overall
implementation. Network availability is an excellent method of looking at
specific areas when implemented at a low level, i.e., by object. There are
several methods in which this can be accomplished in ways that allow the IS
staff to effectively manage the assets.
Most availability reports concentrate only on seeing if the box is there
for a specific time period and then calculating the time not available back
to the total number of time units per the month. Sometimes averages of a
few objects are lumped together to produce a usable sum. The truth is,
most of these types of availability reports don't do anything constructive
but pacify upper management. If the data for availability focused instead
on a weighted metric depicting importance of the service provided and what
was actually happening during downtime, such as scheduled maintenance,
unscheduled maintenance, lost connectivity due to something else failing,
definitive actions could be taken to circumvent some of the problems.
Effectively, network availability is an excellent tool to "raise the flag"
when a specific service is becoming unreliable.
Most implementations use a network availability formula similar to the
formula shown in figure 5. This formula is usually geared toward specific
devices on the network or the availability of a trunk. Notice that the
more devices added into the overall calculation, the more obscured the
calculation becomes in that one considers all the devices on the same level
as others and furthermore, the more devices added into the overall average,
the more hidden they become.
This is accomplished for each device, then averaged as a group.
Typical Method of Calculating Availability
Figure 5
Consider a Server that is plagued by problems and achieves an actual
availability of 20%. If 99 other devices are added into the calculation
with each of those achieving 100% availability, the real problem area is
obscured. The availability of a device or service is used to identify
problem areas so that they can be corrected. It is not to pacify management
showing good high numbers when the actual service that has been a problem,
is considered 100% available!
Another method of accomplishing availability is to gather a list of
services, provided on the network, by priority. Report on the availability
of each of the services on a monthly basis. Use a modifier or weighting on
those services that are considered more important to the organization.
Telling management the truth about the availability of services provides an
avenue to correct those things that are having problems and provide better
services to the end user community. In the formula figure 6, one can see
how specific services can be weighed according to importance to the
business units.
Example Method reported by Service
Figure 6
Response Times Reporting
The response time associated with specific network services is really
important to the level of service the end user receives. Response time
across the network also affects how well certain protocols and interfaces
perform such as NFS, X-Windows and Client/Server implementations using RPC
mechanisms.
LAN/WAN
One of the big misconceptions of Routers is that if you have a T1 link
(1.544 Mbps) attached to an interface, you can actually sustain a full link
in data throughput. Routers never really utilize a link to 100% but rather
70 to 80% is a better figure. When utilization goes up on the link actual
utilization does not. The response time does, however, along with buffer
utilization. By monitoring the actual utilization and correlating this
data back to buffer utilizations and the response times across the
interface, one can derive a much more informed picture of the actual link
utilization.
Another misconception in measuring response time is the use of ICMP ping
statistics. Because ICMP echo requests and responses are probably dead
last on the priority in which protocols are serviced on most boxes, the
data collected through pings may or may not be accurate dependent upon how
busy the device was at that particular instant in time. A much more
accurate method of collecting valid response time data is using SunNet
Manager's proxy MIB "ippath" or using traceroute which is available in the
public domain.
Inversely, one can monitor ICMP Source Quenches to see if the interface is
being flooded or the system can not respond quickly enough for the data
coming in. This specific problem is common to Unix Servers that do not
have enough swap space or are sized to small for the applications services
they provide.
Some RMON devices can provide statistics on the interpacket delay between
two nodes on the network. This is especially handy when monitoring
protocols other than IP such as Novell's IPX/SPX.
Routers are an excellent source of echo response data provided one can
script through the process with either a console port attachment or via
Telnet. For example, Cisco routers can ping a device using the Appletalk
protocol.
SNA/Netview
Response times measurements have been an important feature to monitoring
the health of SNA networks for years. Not only terminal to host response
times could be monitored -- application response times, DASD (Disk drive)
response times and host to host response times could be monitored and
reported.
Electronic Mail
Electronic mail typically uses a store and forward methodology to exchange
data across the network. Additionally, many implementations use gateways
between disparate mail systems so that end users may exchange mail across
computing environments. The ability to measure the time taken to send a
message across a system or gateway is very important to measuring the
health and status of the electronic mail as a total system. There are
third party systems being marketed today that accomplish just this task,
like Baranoff Mailcheck.
Applications
Some applications have audit trails associated with them to allow someone
to monitor performance and response time. These applications, like Oracle,
Sybase, Informix, keep transaction tables that can be parsed and used to
measure performance.
There are applications available today that will monitor applications
performance on the Server. These applications typically provide an avenue
to monitor an applications performance on a server and report problems.
Additionally, they organize the available data associated with the actual
resource utilizations so that systems personnel can keep the service at an
optimum performance level.
Network Utilization Reporting
What about network utilization reports? Most network management systems,
especially SNMP managers take one MIB variable and plot the delta. Who
ever thought of comparing an overall link utilization with the types of
protocols and errors occurring over the same link. Network utilization
reports let the local personnel plan for capacity of systems, links and
segments. Networks can be optimized readily from the data provided in
utilization type reports. All the data in world isn't any good unless you
can compare it to other elements as required. Furthermore, these reports
need to be accomplished on a local level so what if type scenarios
can be accomplished for best results.
Network utilization can be measured from SNMP based managed objects using
the MIB 2 ifinput and ifoutput tables of a router, bridge or concentrator.
These types of interfaces are usually considered promiscuous in that they
listen for all packets regardless of destination.
Using RMON Pods, one can get excellent information concerning the
utilization of the network they are attached to. Remember though, that any
device that performs bridging or routing will effectively blocks
utilization measurements without deploying a Pod on that specific segment.
Statistics such as traffic by protocol, by node address and connection
lists enable analysis of the traffic on the segment in a very detailed
fashion.
While implementing a response time measurement on a LAN or WAN, it is very
smart to check the accuracy of the information you are gathering. Use a
good protocol analyzer such as a Network General Expert Sniffer or H-P LAN
Probe.
On Wide Area Networks, some utilizations can be accomplished on some
devices, usually only for devices that dynamically allocate bandwidth as
required. Some high end multiplexers can provide this data. ATM Switches
and Hubs definitely can provide this data usually through the ATM MIB or
through an Enterprise MIB associated with the device itself.
Telephone trunk utilizations are available through most Switch and PABX vendors although not usually using SNMP. Most have a terminal interface that can be used to poll the data from. Some implementations use a Call Accounting system to record detailed utilizations of the telephone trunks and stations.
Alarms and Alerts
What about the reporting of real time alarms and alerts? These need to be
processed on a near real time basis. The data needs to be disseminated as
fast as possible to the concerned parties in a meaningful manner. The Help
Desk is usually the best place to send these alerts but the problem is that
the "Some variable = 0" type message doesn't mean anything to that Help
Desk person -- unless you are using experts on your Help Desk! The cryptic
data needs to be converted to a format Help Desk personnel can understand.
Second, what does the Help Desk person do once a message is received? The
Help Desk person may not know about Unix or Windows NT or a specific
network component. The network management application must place, at their
fingertips, a list of processes to be accomplished once an alarm has been
displayed. Information such as who to call, procedures to accomplish, who
to page, needs to be available at their desktop to effectively track a
problem through. Remember, if a Help Desk person doesn't know what to do,
they could spend the next few critical minutes trying to find out where to
start. This time is dead or non-productive time and should be eliminated
if at all possible. If a Help Desk person receives a symptom via the
telephone, if they have to return a call, costs the company 10-20 minutes
every occurrence.
It is through this "Knowledge Base" that Mean Time To Repair (MTTR) cycles
get more efficient. Think about it; a problem is detected faster, a Help
Desk person sees the alarm and starts the diagnostic process, then
dispatches the technician with enough information to know the most probable
cause (what parts to take!) of the problem.
The actual alarm display needs to be simple and informative. By focusing
these messages away from graphical depiction, distribution of the
information is made much simpler -- and faster. Textual messages can even
be displayed easily on a VT-100 terminal dialed into a terminal server.
Another example is to pass critical alarms to a display pager, especially
during off hours or weekends.
Alarm correlation is the process by which several alarms are narrowed from
a mass of problems to a root cause and side effects. Most software vendors
for network management systems sell artificial intelligence based inference
engines to correlate the alarms to a most probable cause -- some even
produce a percentage of probability on which device is causing the problem!
Is this really necessary? The data associated with these inference engines
are based on the relationships between components as illustrated in figure
4. When you analyze what the inference engine is doing, one quickly
realizes that maybe all the artificial intelligence really isn't
necessary. Figure 5 illustrates how to accomplish the same task using
simple database relationships -- minus the percentages calculation on which
device is causing the problem and minus the serious horsepower associated
with deriving this calculation! That is something the on-site engineer has
an idea of already -- once he's pointed in the right direction.
Alarm correlation is good in that it narrows the possibilities to a
common denominator. Once alarm correlation is accomplished, other
tasks can take place automatically such as auto-generation of a Trouble
Ticket or technician paging. Even auto healing mechanisms can be initiated
once alarm correlation has occurred, i.e., a redundant circuit could be
brought on line while the defective link be placed in standby.
Figure 7
In figure 7, if the T1 link goes down, all systems behind it are considered
down. When the element managers for each of the devices report alarms,
alarm correlation analyzes the relationship between all of the alarms and
deduces a most probable cause. This is based on, most likely, a rules
based inference engine, analyzing the relationships between the alarmed
entities.
If true artificial intelligence is to be applied, most implementations
leave out significant information pertinent to proper correlation. Most
artificial intelligence applications deal specifically with two types of
data; rules based information and heuristic information. Rules based
information is that information that can be used to depict entity
relationships and how those entities interact with each other. As such,
most rules tables are static in nature in that one inputs the information
associated with the relationships. The second type, heuristic information,
is the dynamic information derived from previous conditions that have
occurred.
This same relationship can be accomplished in a database much simpler than
the artificial intelligence based solution. The artificial intelligence
based solution will provide a method of calculating, on a percentage
basis, the most probable cause of the root alarm. Root alarms are those
alarms that actually have something wrong. A side effect alarm is one
where the alarm is caused by a failure external to the managed object. In
figure 5, a failure on the T1 link actually reports alarms as follows:
T1 Link - Root Cause
Router - Side Effect
Video Codec - Side Effect
PBX - Side Effect
The database table could be set up in the following manner:
Parent Sibling Managed Object Address Location etc.
T1 Link Multiplexer 1 0 XYZ
T1 Link Multiplexer 2 0 ABC
Multiplexer 1 Serial1 Router 1 1.1.1.1 XYZ
Multiplexer 1 Port5 VC 1 1.1.1.2 XYZ Video Codec
Multiplexer 1 card 25-1 PBX 1 1.1.1.3 XYZ ACME PBX
By searching through a configuration table such as the one above, you can
see how easy alarm correlation really is. By building these relationships
and relating a table of active alarms back to the relationships between
managed objects, it is relatively easy to narrow down to a common
denominator. Simply parsing through the table looking for the highest
point in the parent - child relationship yields the same result as the AI
inference engine. (In a lot shorter time but minus the probability of
failure calculation)
Heuristic information can also be derived provided access to alarm or
symptom histories is provided to some extent.
Help Desk Integration
The Help desk is the key to any service based organization. They are the
direct line to users having problems, tracking problems through to
completion and coordinating activities with the user community. As such,
the information associated with network alarms and alerts needs to be
distributed to them in a language they can understand. Translation of
cryptic messages such as link operationalStatus = 0 to interface
X on device Y went down is mandatory. They, above all other sections
associated with an MIS organization, need real time, pertinent information
concerning problems, alerts and alarms.
Many network management systems in operation today, do nothing to pass
information to the Help Desk - unless Engineering types are manning the
Help Desk. This is where these applications really miss the boat in that
they have been written by programmers and engineers without looking at the
business case. Some of the programs were even written by programmers that
have never had to support a network or so it seems. The real business case
is that you want the Help Desk personnel to be well informed and have
helpful information at their fingertips. When the actual work process flow
is documented, one easily sees that key processes are handled by the Help
Desk. The more informed they are, the less time is taken in getting a
problem resolution on its way to be accomplished. If they have to find out
what's going on and call the user back, the time taken from the time a
problem has been detected to the time a technician is dispatched is
increased dramatically.
The overall key to success in the operation of an MIS department is not to
hire expensive high level engineers to accomplish the work. People are
more motivated when they are hired and trained within the organization.
This is also the most cost effective if the expertise of the organization
is distributed to those lacking specific knowledge in those areas.
Building a knowledge base of symptoms and the tasks associated with finding
and correcting those problems just makes good common sense.
In the knowledge base, tasks such as check certain things, call this
technician or page this guy or even to ask questions to gather information,
places, at the fingertips of the Help Desk person, clear, definitive tasks
to accomplish to get the ball rolling.
By the process of elimination, a list of probable causes can be narrowed to
a single probable cause just by looking at a couple of things and asking
the right questions.
Building this knowledge base and deploying it throughout the organization,
enables new personnel to be productive day one. Furthermore, it takes the
knowledge of all (i.e. Desktop support, Server Support, Database Support,
Network Support, Unix Systems Support, etc.), collects that information in
a process flow format, and distributes it to all concerned.
Once a problem has been detected and the ball is rolling on getting the
problem owned by a Help Desk technician, a trouble ticket needs to be
initiated. This is vital in that it allows MIS organizations to monitor
the type of work being accomplished and by whom. It is also a key function
in gathering the necessary information to calculate the cost of
maintenance. By knowing your costs, you can work to get the costs down.
Data such as the number of specific models of hard drives or video cards
that have been repaired or replaced over the last month, quarter or year,
allow the MIS Manager to weed out those devices that cost too much
to repair. Analyses of this sort typically drive the cost of maintenance
down greater than 20%. Because of the rollover of technology, these things
need to be monitored in that it may be more economically feasible to
replace a whole desktop computer than to have a hard drive controller
replaced. Best of all, the end user feels as if they are being taken care
of. Consider this; the customer is happy because the service is focused
toward them and money is saved because it costs less to replace that aging
old box that kept breaking.
The ability to track the workload by department is an excellent tool for
management to analyze the number of personnel by skill and adjusting the
technicians to the work at hand. The Trouble Ticket application, if
integrated with network management, provides an easy flow of work and
information in tracking problems from start to analysis after the fact.
The trouble ticket must integrate well into the way the people accomplish
work. Focus on the business case and the work flow process.
Some trouble ticketing systems allow the technician to check inventory for
a specific part while on line, generate an overnight shipping label or
automatically flag an item that is low in inventory.
Trouble ticketing systems must have the ability to track Warranty and
maintenance administration information in an easy to use method. So many
organizations buy new equipment but do not track the Warranty information
until someone raises the flag that a maintenance contract is needed on the
specific type of device. If maintenance contracts do not start when
warranty ends, additional charges can be expected. All of these additional
costs, lost time in getting a part plus the additional 10 to 20% for
maintenance contract penalties, add up to money thrown away.
Once an alarm has been received, there are several steps required to
correct the problem associated with the alarm or symptom. Each alarm
received should look like a real symptom that makes sense to the user
community... not just something is down because some variable equals 0.
Figure 8 depicts a common process flow diagram for receiving and correcting
problems.
Figure 8
The automation of processes that take an inordinate amount of time to
accomplish, needs to be analyzed and fitted into the overall application.
Tasks where support personnel check to see if an event happened need to be
looked at very closely to see if this event can be flagged and sent as an
alert to the overall application. In this manner, dead time such as
time spent just seeing if something has happened or if something is still
working, can be eliminated. The Network Management System, as a whole must
address these types of needs in that they must be easy to add new types of
element management functions quickly without having to rebuild the whole
system every time.
One example is an MIS department that had one person spending around five
hours a day checking electronic mail connectivity across Microsoft Mail and
various gateways to other types of mail systems, such as SMTP, X.400,
Profs, All-in-1, and CC:Mail. Wouldn't this type of work flow problem be
solved easily by building an Electronic Mail poller that sent messages to
echo type mailboxes across the various systems. By polling across the
systems, response time and connectivity could be checked in an automated
fashion. If the data associated with this system were forwarded and parsed
into the Network Management application, the Electronic Mail Support person
could be freed up to accomplish other tasks associated with his or her
department. Only if a problem was found, would the concern arise.
In general though, these requirements need to be driven by the actual work
flow processes currently in place and trying to save time and money by
shortening these processes.
When a system is deployed across multiple sites and multiple organizations,
communications between the various workgroups enables planning, maintenance
and, best of all, knowledge, to be shared across the organization. Tools
that enable people to express ideas, work out solutions as a group, or just
to ask questions from users' desktops are drastically needed. These
types of tools, commonly referred to as Groupware, enable people to promote
team building skills... no matter where they are located physically. It is
a known fact that people work better when they feel as though they belong
to a team.
Groupware tools include Group Sketch or Whiteboarding, Group chat,
Brainstorming, Group postit notes, group editing and the like really add to
ways' people can interact. The exchange of ideas and information across
departments, site and countries tend to get the whole organizations working
together.
Now that we've been over some of the business cases on how an ideal network
management application should be implemented, let's put the pieces
together.
Figure 9
User Interface
Figure 10
Management Functional Domains (MFD's) are the segmentation of the
Enterprise Network Management System into localized functional domains.
The grouping of functions within specific domains allows alarm messages to
be routed around problems or faults especially when multiple paths exist.
Furthermore, automated SLIP or PPP sessions will enable alarm passing
through dialup lines.
Not just alarm messages need to be passed to other affected MFD's. Alarm
correlation information and automatic diagnostics are examples of other
information relative to a fault that provide a better picture of what's
really happening on the other end.
Figure 11
Figure 12
Figure 13
In the above three examples, each of the sites or MFD's, visualize an alarm
on the link and several alarms on the other side of the link. This is
because the link fault is the root cause and all the rest of the alarms are
side effects. By being able to validate the alarms across a broken link,
one can quickly and efficiently determine the root cause. CPU utilization
associated with correlating the alarms is very low compared to the AI
Inference engine based Alarm correlation. One simply looks for alarms that
are common to both sides.
Figure 14
Following are a list of steps to take to develop a requirements matrix
associated with the management of network components and functions.
- Develop a list of information attainable from each managed object.
Describe in detail, each piece of information such as what the data
element is, average versus actual, counter, raw integer or a text
message.
- Take the list to the Support organization responsible for that device
function and have them decide what's pertinent to their way of doing
business. Focus on information that will enhance their ability to
accomplish their job in an easier manner.
- Formulate the reporting strategy for the device.
- What elements of information are pertinent to alarm
reporting. (Realtime)
- Establish thresholds. i.e. three counts in a one hour time
period.
- Establish the priority of the alarm and any thresholds
associated with priority escalation of the alarm.
- Establish any diagnostic processes that could be run
automatically or the Help Desk could perform that would
make their job easier.
- Establish acceptable polling intervals (Every five
minutes, ten minutes, one hour, etc.)
- What elements of information are pertinent to monthly reporting.
- Availability of devices and services.
- Usage and load.
- What elements of information are pertinent to trending and
performance tuning of network components and functions.
- Look at ways to combine data elements or perform
calculations on the data to make it more useful to the
support organization.
- Interview Management to ensure the Network Management System is
managing all areas pertinent to the business unit.
- Explain the role and objectives of the Network Management System.
- Increase productivity throughout the support organizations.
- Reduce the Mean Time to Repair times on the correction of
problems.
- Provide a proactive approach to the detection and isolation
of problems.
- Enable collaboration and the flow of information across
support departments and sites.
- Gather the requirements for the management of any function
important to the business unit.
- Don't limit these functions to only SNMP manageable devices.
- If the devices associated with a function have no intelligence
whatsoever, go back to management later with a proposal to
upgrade the devices.
- Go implement the requirements. Focus each implementation toward each
requirement while integrating the total system.
- After implementation of each piece, notify the support organization
associated with the managed object or system that monitoring has started.
- At the first reporting period, go back and revisit the requirements
with each support organization and management.
- Reestablish requirements if necessary.
- Be advised that the reports and types of data will change as
each support organization becomes better informed.
During implementation, focus the alarm messages toward the Help Desk. They
are the front line of any MIS organization. Keeping them well informed of
problems is paramount to the successful deployment of the Network
Management System.
Perform "Dry Runs" of alarms and the diagnostic steps associated with
getting the problem on the road to resolution in a quick and efficient
manner. Have the appropriate support organizations participate so that all
diagnostic steps can be identified and included. Don't leave out any
management notifications that may be necessary.
Train the Help Desk to input troubleshooting procedure pertinent to their
function into the diagnostics table. This can include anything from a user
calling in with a problem with an application (i.e. MS Word), to filling
out forms for a specific service to be provided to an end user.
The skills associated with the support organizations in one MFD may be
different from another MFD. The gathering of diagnostic procedures allows
a "sharing of the wealth" of knowledge across the enterprise. The
diagnostics procedures are a knowledge base of information, by symptom, of
problems and taskings and what needs to be accomplished to correct the
problem. Having the skills of Desktop Support, Unix System Support,
Network Support, etc., at the fingertips of Help Desk personnel increases
their ability to logically react to problems as their occur.
The Network Management System, as a total integrated system, must be
modular and easy to expand and contract as the needs of the business
change.
Element Management Systems, whether they are third party products such as
SunNet Manager, HP Openview, Netview 6000, Netview, NetMaster, 3M TOPAZ,
Larsecom's Integra-T, or in-house developed pollers, need to be easy to
integrate into the whole system. Recognize that in the architecture, no
EMS is really aware of another. Awareness across EMS's needs to be
accomplished at a higher layer so that the EMS's can focus on their area of
management within their MFD.
Functions such as Alarm Correlation, Diagnostics across EMS's, etc., can
be accomplished using artificial intelligence principals within a
relational database. Almost all Manager of Manager products employ an AI
Inference engine to calculate the probability that one component is so many
percent more probable to break versus another. The inclusion of the AI
Inference Engine drives up the cost because of the engine AND the iron to
run these types of calculations. These types of decisions need to be
accomplished through the support organizations within the MFD because these
folks know the local environment better than any machine or personnel at
another site. Doesn't the overall application serve it's purpose better if
it is more tightly integrated into the business units?
The application of AI still needs to be applied but at a much different
level. Network General Distributed Sniffer Servers are an excellent
application of AI technology. By analyzing the relationships of protocols,
traffic, connections and LAN control mechanisms. The DSS uses AI to sort
out problems at a very low level before they become user identifiable
problems and cause degradation or downtime.
Additionally, artificial intelligence can be used to capture the heuristics
of network behavior and help with the diagnostics. The information
available from past alarms of similar problems associated with what was
accomplished to isolate and correct the problem needs to be incorporated
into the overall system.
As an MIS Manager, when you are approached by staff or vendors concerning
Network Management, there are a few key questions to ask.
How much will the system cost?
A lot of systems implemented today are accomplished by a Salesman
specifying the system to the MIS Manager. They typically push huge amounts
of hardware and software at the problems at hand. Some vendors will even
tell you that cost is not important; it's the capability that counts.
Additionally, because a network management system must be customized to the
local environment, there are a lot of hidden costs beyond the hardware and
software.
Will the proposed system integrate into and enhance my current MIS
support capabilities?
A lot of MIS Managers really miss the boat by not demanding that the
overall system be tightly integrated into the business units. If the
system serves no business purpose, you buying technology for technology's
sake... the system is doomed to failure.
Is the proposed system modular in design?
If everything in a Network Management System is loaded on one box, you're
setting yourself up for inefficient use of computing resources. If the
system contracts, the one box will be underutilized; if it expands, you'll
be trading that box in for a bigger one... losing money every time.
Is the product proposed just an Element Management System or is it an
Integrator of Element Management Systems?
Too many times, MIS Managers are sold a product like HP Openview or IBM
Netview 6000 as a Manager of Managers System. Although, some integration
functions are capable in these systems, you take away from their ability to
perform real work... like polling and gathering information.
What does the system monitor?
Match the capabilities of the proposed Network Management System to the key
I/T services provided. If it is not a good match now, it won't be later.
Does the proposed system enhance the capabilities of the current support staff or does it add more support staff?
Be especially careful in that some systems will do nothing to enhance your
current support staff capabilities and add five or ten more personnel to
your staff and to your budget. Not to mention, these people are usually
highly skilled specialists in Network Management... which don't come
cheap.
Look at the total picture of the entire enterprise and match what is
proposed to what's currently operational. Ask the same questions for each
site.
There are a lot of excellent products available today that provide
capabilities to manage not just hardware, but services and applications.
The way that these systems are implemented are also critical in that each
management capability installed must match a business need for such a
system. Additionally, these diverse systems must be integrated together
and into the support organizations to achieve maximum effectiveness.
Author: Douglas W. Stevenson
HTML Conversion: Jeff Murphy jcmurphy@acsu.buffalo.edu