WEB-BASED MANAGEMENT

WEB
-
BASED MANAGEMENT




INTRODUCTION:



The method that illustrates the use of SNMP network management with a web
-
interface has tha
t

following
steps, initially

the data are gathered by
SNMP

counters
, analysed

and then stored in web pages.

These pages are
stored in web
servers and accessed via web browsers.

With the rapid usage of web technology combining Network or system management to gather data,

And web technology to display the information at multiple lo
cations seems logical. However w
e can use
web te
chnology to both gather and display
data.



NMS WITH WEB INTERFACE AND WEB BASED
MANAGEMENT






The
web interface

deals with how information is presented to the
user. This

communication is based

On TCP/IP protocol
i.e.

the server conv
erts the information to web pages and presents to the user.


A similar approach exists in an SNMP bases
management. In

its pure
implementation web

based
management is based on web
technology. In this

the agent is embedded in the network element as a web
se
rver and can monitor and/or control the network element.



WEB INTERFACE TO SNMP MANAGEMENT


Two approaches are available.

1) Short
-
term

approach is to add a web interface to an existing management system.

2) To have a web based system with embedded web ag
ents in the network components.

Method1

description:














NMS
SNMP Manager
Managed Objects
SNMP Agent
Web Server
Web Browser
NMS Console
Desktop PC
Figure 14.1 SNMP NMS with Web Interface
SNMP
HTTP

The most common implementation is to have a web server on an
NMS
platform with an interface to

NMS.The SNMP
-
NMS

implementation

I platform and operating system specific and agents are
SNMP

agents. The protocol

between agents and managers is SNMP
communication

protocol traversing

o
ver UDP/IP.

The protocol between server and browser is HTTP traversing the internet.























The architecture of proxy server is similar
to SNMP

NM
S with a interface but NMS replaced by a proxy
server. The NMS

console is eliminated which is a economic advantage
.
No GUI in manager applications.

Another advantage is proxy server
can

be implemented an any platform and protocol between agents

And proxy s
erver can be SNMP
are

any other protocol.



EMBEDDED WEB BASED MANAGEMENT










Proxy Server
Manager
Applications
Managed Objects
SNMP / Other
Agent
Web Server
Web Browser
Desktop PC
Figure 14.2 Proxy Server with Web Interface
SNMP/
Other
HTTP
Manager
Applications
Managed Objects
Web Server
Web Browser
Workstation/PC
Figure 14.3 Embedded WBM Configuration
HTTP




Here web

servers are embedded in the main
objects
.

1) WEB

servers read counters and pass information to the manager
are

respond to a
ping. Communication

between agent
and manages application is
HTTP. The

web agents in network elements greatly simplify

N/w

management for n/w administrators.

2) Another

benefit of embedde
d WBM is we can make use of porta
ble tools to write to web agents.e.g in

Java.

3) Commercial

n/w produ
cts with built in web agents are
available, but

they are based on proprietary
protocols.


















The above shows the configuration of both web and non
-
web agents.

a)
Web

agents function and provide data much the same as RMON
does. Communication

t
o the manager


Application/web

browser called the HP ADVANCE STACK ASSISTANT is via the HTTP


Transport protocol
.

B) Non

web agents are managed by web
agents.
This

is beneficial for 2 reasons.

i.e a n/w element wi
thout a web agent can be managed

in

a we
b based environment. And second the

Configuration

enables remote probing of switched LANS.




DESKTOP MANAGER INTERFACE

The desktop management
interface (
DMI) is an industry
standard

generated by DMTF
, started

in 1992 to
develop, support and maintain manag
ement standards
for

Pc systems and
products. It

is between computer
components
and application
. s/w

.The management application is a desktop resident
program. The

component

agents are s/w
agents. The

components can be s/w(virus checker),h/w(n/w interface c
ard) or
firmware (Pentium chip).



Manager
Applications
Managed Objects
http
Web Agent
Web Browser
Workstation/PC
Figure 14.4 Hewlett-Packard Embedded Agent Configuration
http
SNMP
Non-Web Agent
















To permit multiple vendors products to be managed
by a

common application
program

2 standards are
specified in DMI.

•


Management information format (MIF),


similar to MIB

•


Program interface with two API
s






















•

Architecture has dual representation

•


Version 1 with data block component I/F

•


Version 2 with procedural component I/F


Version 1.x compatibility with block interfaces and version 2.0s has user friendly
procedural

interfaces.

Desktop Management Interface software (DMI)
Management Interface API
Component Interface API
Component
Agents
Desktop-resident
Management Application
MIF
Database
Figure 14.5 DMI Infrastructure
DMI Service Provider
SP/MIF
Database
Management Interface Server
RPC Support
MI Interface
Client
Indication
Server
RPC Support
MI Interface
Client
Indication
Server
Local Block
Interface
Application
Data Block Mgmt
Interface
RPC SUPPORT
Indication Client
Data Block Component
Interface
Procedural Component Interface
Block CI
Component
(HW/SW)
Procedural CI
Hardware
Component
Procedural CI
Software
Component
Procedural CI
Firmware
Component
RPC to/from
Remote Systems
Figure 14.6 DMI Functional Block Diagram

CI
procedural components interface in h/w,

s/w, and firmware with the procedural component interface API
in the DMI service
provider.
Communication
between the

DMI server provider and remote station use RPC.
Three
RPCS
provide support in 3 different environme
nts

1) DCE
/RPC supports the distributed computing environment

used by IBM and Microsoft.

2) ONC
/RPC (open n/w computing
) supports

the UNIX environment used by sun workstations.

3) TI
/RPC supports the transport independent environment supported by Novell Ne
tworks.






















•

MIF specified using ASN.1 syntax
. Objects are grouped and multiple instantions from tables as in
SNMP management.

•



DMI
-
Managed objects c
an be managed by an SNMP manager

•


DMTF
task expanded to specify WBEM
-

Web
-
based enterpri
se management
.




WEB
-
BASED ENTERPRISE MANAGEMENT



DMTF has under
taken a

broader WBEM task . The goal of the assignment was to unify and

Extend

the existing instrumentation and management standards by using object oriented

Constructs

and design

.
WBEM b
ased o
n Common Information
Module,

developed

by

Microsoft
. The

CIM approach is to preserve and extend traditional management information
sources,
such

as SNMP and DMI.

T
he result has been useful for both Internet and internet services.

CIM is informat
ion
-
modeling framework
intended

to

accommodate all protocols and frameworks

And an approach to the management of enterprise systems
, software, users

and network.


It
uses
Object
-
oriented

structures and concepts.


enterprises
(1)
dmtf
(412)
dmiMIB
(1)
dmtfStdMifs
(2)
dmtfDynOids
(3)
dmiConformance
(3)
dmiNotification
(2)
private
{1 3 6 1.4}
dmiObjects
(1)
Figure 14.7 DMI MIB





















WBEM has f
ive components:

•


Web client

•


CIM object manager (CIMOM)

•


CIM schema

•


Management protocol

•


Managed objects with specific protocol



•

The web client is
a

web browser with management
applications. The

browser uses HTML for
presenting management data.

Application requests use

CIM schema



Multiple instances of Web clients feasible

•

The applications involve issuing a request and the request is iss
ued against an object in the CMI

sche
ma and is sent to the CIMOM via

t
h
e HTTP.

•


CIM object manger

forms the heart of WBEM

architec
ture and

mediates between Web clients,


managed objects, and CIM schema
.The objects to and from CIMOM use

HTTP as a transport
protocol .It

processes the messages from clients and managed objects.


a)
Microsoft Windows Management Instrumentation



uses Distributed Component Object Model (DCOM)


b)

Sun’s CIMOM uses JMX

•

The protocol providers are between CIMOM and the protocol specific managed netwo
r
ks.

Ex: SNMP provider between CIMOM
and SNMP

managed objects network and


D
MI provider between CIMOM and managed DMI managed object network

The message between a protocol provider and
CIMOM uses

HTTP.

The common model embodied in CIMOM can be implemented in several ways.

TWO models are actively being implemented JAVA management e
xtensions and WBEM.





Web Client
SNMP
Managed Objects
DMI
Managed Objects
DMI Provider
SNMP Provider
CIM
Object Manager
(CIMOM)
CIM
Schema
Management
Applications
Web Browser
Desktop PC
HTTP
HTTP
HTTP
SNMP
RPC
CIM
Managed Objects
HTTP
Figure 14.8 WBEM Architecture
SNMP Agent
DMI Agent
CIM Agent

CIM consists of three modules.

•

Core model: high level framework

•


Common models: protocol
-
specific domains

•


Extension model: technology specific





















•

Solid lines indicate inheritances

•


Dashed lines indicate associa
tions

•


Physical El
ement

(e.g. interface card) and
Logical Element

(IP address) subclasses of


ManagedSystemElement.

•

A physical element can have multiple logical elements.

•

Logical device,system,service and service access points are subclasses of the logica
l element

•

System is aggregate of managed system elements

•

Service access poi
nt is management, measurement,
and configuration of a service Managed


System

el
ement considered as groups of
components
.

Managed system elements can be viewed as groups of co
mponents .They are network components,
system components and application
components
.


WBEM
:

WINDOWS MANAGEMENT INSTRUMENTATION

•

WMI is Microsoft infrastructure to support WBEM CIM

•


WMI comprises management infrastructure,
management

applications, and

provid
ers of data from
managed objects.


•

CIM is the CIM schema

•


Object providers are management agents (e.g. SNMP


agent)




Application Component
Resource Component
ManagedSystemElement
PhysicalElement
LogicalElement
System
Network Component
Logical Device
ServiceAccessPoint
Service
Realizes
Component
(views)
ServiceSAPDependency
Figure 14.9 WBEM CIM Core Model
SystemDevice
HostedService
ServiceAccessBySAP
SystemComponent
Product
SupportAccess
ProductSupport
ProductPhysicalElements
ProductParentChild
HostedAccessPoint























•

The infrastructure includes CIMOM and WMI repository.


•

CIMOM has
snap
-
in management applications
.

•

The communic
ation path in an out of CIMOM uses the IWBEMSERVICES feature of
COM/DCOM..Its services include object creation,deletion,data
retrieval, event

notification


And

query processing.

•

WMI
repository is

the central storage area for management data. The dat
a change between

•


CIMOM and WMI repository uses either the WBEM Managed Object Format language or
COM/DCOM API
.



JAVA MANAGEMENT EXTENSIONS

JMX is the another

approach to develop a common mo
del for total management using
Web technology
.

It defines manage
ment architecture,

API’s and management services under a single specification.

It evolved from java API. JMX is based on java development
kit (
JDMK).


SERVICE DRIVEN NETWORK

•

Network of services (instead of network of


components)

•


Service needs provisio
ning and management

•


Web phone

is Internet analogy to telephone

•


Web phone

is

mini web browser

network
-
centric device (th
in client,

hand
-
held device)

•


Web phone

is a plug
-
in device in service network

•


Java technology calls plug
-
in
Java Bean

•


MBean is man
agement
Java Bean
which

can be added to
or

be part of a plug
-
in.

CIM Object Manager
Repository
MOF Language
COM/DCOM API
Object Providers
WMI
Objects
WMI
SNMP
Objects
SNMP
DMI
Objects
RPC
Win 32
Objects
Win 32
Other
Objects
COM/DCOM
IWbemServices
Management
Applications
Snap-in
Snap-in
COM/DCOM
IWbemServices
Figure 14.10 WMI Architecture

JDMK


















•

Java dynamic management tool kit

is u
s
ed to build

Java
-
based NMS

agents.

•


MBean is an intellige
nt agent; does not need
polling

as

in SNMP agent

and can be built in to
s
ystems, applications and network devices.

•

MBeans can be loaded dynamically as java has
b
uilt in integrity schemes for PUSH and PULL
technologies.

•


JDMK architecture consists of



MBeans, a

core management frame work also known as MBean server an
d


P
rotocol adaptors to communicate

like interfaces to applications.



A
lso

the
special java
-
Bean,

C
-
Bean for Client Bean.


















The flow diagram shows how beans are accessed and moved around various components. It consi
sts of 3
JDMK agents that are under the control of master JDMK agent. Manager is NMS and web server stores
management applications. Any MBean can be pulled out of
Web server

at boot time. The manager pushes
MBean to master agent which in turn pushes to 3 J
DMK agents and services can be cascaded.

Core Management Framework / MBean Server
MBean
MBean
MBean
C-Bean
Protocol
Adaptor
Protocol
Adaptor
Web Server
HTML Adaptor
Figure 14.11 Java Dynamic Management Agent Architecture
Manager
Web Browser
Application
Managed
Object
Managed
Object
Managed
Object
Java
Virtual
Machine
Core Management
Framework
MB
MB
Agent Profile A
Java DMK
Master
Agent
Manager
MB
http://URLA/<Management AppletA>
http://URLB/<Management AppletB>
http://URLC/<Management AppletC>
Web Server
MB
Figure 14.12 Management Bean (MB) Flow
Diagram
MB
B
C
JMX Architecture























•

JMX architecture comprises three levels

•


Instrumentation

•

Specifications for implementing JMX
-
manageable resources are written at this level.

•

JMX
-
manageable resources
include n
etwork devices,
applications, service entities, and systems
.

•


Developed in Java or Java wrappers as MBeans

•


MBeans
can

be
implemented either

as
static

or dynamic

components.

•

Agents

•


MBean server is a

set of services for handling
M
B
eans
,

protocol adaptors

or connectors.

•


JMX
-
manageable resources register
s

with an agent

•


Interface
adaptor to Web browser contains a Web server
.

•


Interface

to

applications in
manager

level is either a protocol adapter

called a connector

•


Protocol adapto
rs represent

MBeans

in an
other
protocol, such as SNMP

manager.

•


Agent
-
Manager com
munication infrastructure uses

HTTP, CORBA/IIOP, etc.

•

Manager

•


Comprises ma
nagement applications, network
manager, and browser

•


Multiple agents i
nterface with
JMX manager via the connector interface a
nd with


Proprietary agents via
the
protocol

adaptors
.

Additional Manager
API’s are

SNMP manager API ,CIM/WBEM API and TMN API.

•


CIM/WBEM APIs are
grouped into CIM, client, and

provider.

•


CIM API re
presents CIM elements as Java
class objects

•


JMX mana
ger interfaces with external database


using JDBC (SQL databases)
.


MBean Server
Service
Protocol
Adaptor
Web Server
HTML Adaptor
Figure 14.13 JMX Components
Java Virtual Machine
Managed
Object
Connector
Instrumentation
Level
Agent Level
Web Browser
Proprietary
Management
Application
Proprietary
Management
Application
JMX Manager
MBean Server
Service
Java Virtual Machine
Connector
SNMP
Manager
API
CIM/WBEM
API
TMN
Manager
API
Additional
Manager
APIs
Manager
Level
Managed
Object
Managed
Object
MANAGEMENT OF A STORAGE AREA NETWORK:

The Jiro Platform

















A mixed management environment of networks, systems, applications, hardware, and the like

might contain a network

of storage areas.CIM schema is a way to address this possibility.

Jiro (pronounced gy
ro) is a platform for managing

storage area network
.

The goal is to develop a solution for management applications that allows the operation of

Storage

area networks on
different vendor platforms.

•


Three
-
tier architecture

•


Jiro core specifies Jiro platform

•


Object model supports distributed objects based


on Java object model

•


Component model is a set of core components


used to build portable applications

Looking Ahea
d



Future
network and system
management
frameworks

should accommodate well
-
established


SNMP entities Web agents are i
ntelligent and future points to

the use of Web technology

•


Web
-
based management offers two options

•

WBEM is comprehensive and centrali
zed approach


to enterprise management; accommodates both


scalar and object
-
oriented schemes• JMX is decentralized and uses Java technology;


agents embedded in objects and can be downloaded


from NMS; platform independent Future NMS environment could

be a merger of the


old and the new
-

at least in the near future


GUI
Web Browser
Jiro Platform
DMI
WMI
JMX
SNMP
CIM
Client Tier
Management Logic Tier
Resources Tier
Figure 14.14 Jiro Architecture
Other