presentation on training project(4)

8/3/2019 Presentation on Training Project(4)

1/25

A

PRESENTATION ON

DATA REPLICATION

INFRASTRUCTUREBy:Nikhil Verma (00576807710 /IT-Vth Sem/ EVE)

Vivek Pasi (02176803109/ IT-Vth Sem/ EVE)

Department of Information Technology

Guru Tegh Bahadur Institute of Technology

Guru Gobind Singh Indraprastha University


2/25

INTRODUCTION

This Project is based on the study of an ongoing process of MTNL

in which data of a main telephone exchange of one city (also

known as main site) is backed up to a local exchange (also known

as the remote site) which in turn has a backup routed to a main site

of another city.

This main site of second city has its own data being backed up at

its remote site location which in turn has a backup routed to the

main site of previous city.

Thus a network of data backups is formed between these sites

through which any data can be accessed by a server at any time and

in case of a disaster, this can help in restoring the affected site to its

previous state.


3/25

VARIOUS TECHNOLOGIES &

EQUIPMENT USED IN THE PROJECT

The following is the list of main equipment used in this project:

1. DS 8000 Copy services environment: DS-8000 copy services

environment was developed by IBM Corp. It was developed to

associate data replication for large scale companies in anefficient & hassle free way. It uses the IBM Corps AIX Server

Operating System based on UNIX.

2. ROUTER: A router is a device that forwards data packets

between telecommunications networks, creating an overlay

internetwork. Router is provided by CISCO.3. SWITCH: A network switch or switching hub is a computer

networking device that connects network segments.

4. SERVER: A server computer is a computer, or series of

computers, that link other computers or electronic devices

together. Servers are provided by IBM.


4/25

What Is Data Replication

Data replication may be defined as the effective sharing of

information between two remote sources so as to establish a

common consistent link between them.

Usually it is done between two remote servers, or similar types of

machines like workstations, where the workload is very high and

there is constant flow of data.

Data replication is very useful in managing large amount of data

particularly in ISP Servers.

Data Replication can be done through various techniques like

database replication, disk replication, file based replication etc.


5/25

Simple Block Diagram Of Data Replication

Infrastructure


6/25

Types Of Data Replication

The following are the types of data replication techniques:

1. Database Replication - Database replication can be used on many databasemanagement systems, usually with a master/slave relationship between the originaland the copies. The master logs the updates, which then ripple through to the slaves.The slave outputs a message stating that it has received the update successfully,thus allowing the sending (and potentially re-sending until successfully applied) ofsubsequent updates.

2. Disk Storage Replication - Active (real-time) storage replication is usuallyimplemented by distributing updates of a block device to several physical harddisks. This way, any file system supported by the operating system can bereplicated without modification, as the file system code works on a level above the

block device driver layer. It is implemented either in hardware (in a disk arraycontroller) or in software (in a device driver)

3. File Based Replication - File base replication is replicating files at a logical levelrather than replicating at the storage block level. There are many different ways ofperforming this and unlike storage level replication , they are almost exclusivelysoftware solutions.


7/25

Uses of Data Replication

There are many Practical applications of Data Replication,

almost everywhere where there is need for data handling and

transfer of large packets of data

Internet Service Providers (ISP) use this technique to backup

their usage data and everything else.

Backing up of data can be very hectic task but it can be easily

managed through data replication techniques.

Sometimes, if the data of a critical storage location for any

company (or any organization) gets lost due to any unwantedproblem or disasters, then this technique can be very helpful in

recovering process.


8/25

ROLE OF DATA REPLICATION

Data Replication can play a veryimportant role in saving substantialamount of data for a company in case ofany disaster occurrence.

It can also help in restoring balance tothe main framework after a disaster has

occurred in order to make the mainframe work recover from it


9/25

The Concept of Mirroring

The Process of Disk mirroring may be defined as the process ofreplicating the contents of a main disk onto another disk so that thecontents of the real disk are replicated on the subordinate one.

This method is used to backup data from a main disk onto a secondarydisk for two reasons:

i. To keep the main Disk free from data clogging

ii. To back up important files that can be lost if the main disk fails

The Concept of data replication uses the process of mirroring for its

operation Usually, the equipment involved in this type of operation is the IBM

Corp.s DS-8000 Copy Services Environment which uses the IBM AIXServer OS.


10/25

Types Of Mirroring

The following are the types of mirroring:

Metro Mirror:

Metro Mirror maybe defined as the type of a disk mirroring function

which can provide real time copying (instantaneous copying of data)

between two disk volumes.

The location of the two disk volumes can be up to 300 km and they are

termed as remote disk volume (the disk onto which the data is being

copied) and the main frame disk (the disk from which the data is being

copied).

It is a synchronous type copying function in which both reading and

writing functions can be performed on both the disks simultaneously.

Simultaneous exchanging of data can be made between the two

participating disks (copying and accessing the data).


11/25

Basic Diagram of Metro Mirror


12/25

Types Of Mirroring (contd.)

Global Mirror:

The Global Mirror function maybe defined as the process in which theexchanging of data between the two volumes takes place after a setinterval of time.

This technology is asynchronous in nature that can provide longdistance copying functions between two remotely located sites (themain frame and remote location).

The range of global mirror functions is very high, only depending onthe network capabilities (like the channel through which the copying isdone etc.)

It works like a distributed application which is based on a clientserver relationship, where the server functions as a supervisor andinstructs the client, which is able to do the work but is reliable on theserver for instructions.


13/25

Basic Diagram Of Global Mirror


14/25

List of Basic Commands Used For Metro

Mirror Operation

TASK Command with DS-CLI

(CLI = Command Line

Inter Face)

Command With DLS-GUI

(GUI = Graphical User

Interface)List available I/O ports that

can be

used to establish Metro Mirror

lsavailpprcport This information is shown duringthe process when a path is

established

List established Metro Mirror

paths.lspprcpath Copy Services Paths

Establish path. mkpprcpath Copy Services Paths Create

Delete path. rmpprcpath Copy Services Paths Delete

Failback. failbackpprc Copy Services Metro Mirror /Global Copy Recovery Failback

Failover. failoverpprc Copy Services Metro Mirror /Global Copy Recovery Failover


15/25

COMPARISION BETWEEN METRO

MIRROR & GLOBAL MIRROR

METRO MIRROR

Mode of operation is

Synchronous

Data consistency is maintained

as long as there are no failures

Data transferring is almost

instantaneous

The remote site is always up to

date with the main site

GLOBAL MIRROR

Mode of operation is

asynchronous Data Consistency is maintained

at the remote site

Data at the remote site lags

behind the main site a little

The data transferred at theremote site is a little behind the

main site


16/25

List of Basic Commands for use with Global

Mirror Operation

TASK DS CLI DLI SMStart Global Mirror session mkgmir CS GM CreateStop Global Mirror session rmgmir CS GM DeletePause Global Mirror session pausegmir CS GM PauseResume Global Mirror session resumegmir CS GM ResumeShow Global Mirror status showgmir CS GM PropertiesCreate a Global Mirror session mksession CS GM Create

Or

CS

GM

Modify

Remove a Global Mirror session rmsession CS GM DeleteOr

CS GM ModifyChange a Global Mirror session chsession CS GM ModifyDisplay a Global Mirror session lssession CS GM View session volumes


17/25

List of commands for use with Global

Mirror Operations (contd.)

Create a complete Global

Mirror environmentmkpprcpath

mkpprc

mkflash

mksession

mkgmir

CS P Create

CS MM Create

CS FC Create

CS GM CreateFail over Global Mirror rmgmir

failoverpprc

lsflash

revertflash

or

commitflash

reverseflash

mkflash

CS GM Delete

CS MM Failover

CS FC Properties

CS FC Reverse

relationship

CSFCCreate

Fail back Global Mirror mkpprcpathfailbackpprc

lspprc

mkpprcpath

failoverpprc

failbackpprc

resumegmir

CSPCreate

CSMMFailback

CSMM Properties

CSMM Failover

CSMM Failback

CSGM Resume

TASK DS CLI DLI SM


18/25

Failover And Failback Functions

The failover and failback functions may be defined as the two main

disaster management functions that can be employed if any unwanted

situation causes the main site of data generation (data center) to crash

or stop functioning. In this, there may be two steps involved:

1. During the first step, if the data center stops functioning in the

normal way, then the data replication is handled from a remote data

site. This process can be termed as the failover function.

2. During the second step, when the main data center is working

properly, the work is shifted again from the remote site to the main

center, with the emphasis being laid on updating the main data center

before continuing any work on it. This process can be termed as the

failback function.


19/25

SUMMARY

Data Replication Infrastructure is a network of interconnected Locations (known as main

& remote sites) which does replication (copying) between two subsequent Main &Remote Sites.

It is used to backup critical data from a main site to a remote one so that the data can bebacked up to a safe location which may be used at the time of need

Most prominent form of data replication is the disk replication system

In disk replication system, there are further two types:

1. Metro Mirroring

2. Global Mirroring

Mirroring can be defined as the process of replicating the exact contents of a disk on toanother one

In metro mirror, the data from the main site is replicated to the remote siteinstantaneously.

In global mirror, the data from the main site is replicated to the remote site after a timeinterval.

Failover and failback functions are the two functions which help in the disaster recoveryprocess.

This whole process is based on the IBM Corps AIX Server OS, using DS 8000 DataReplication Services.


20/25

SNAPSHOTS OF VARIOUS

EQUIPMENT BEING USED AT MTNL

A HARDWARE MANAGEMENT CONSOLE

(USED FOR MAINTAINING A SERVER)


21/25

A ROUTER & SWITCH ASSEMBLY


22/25

SERVER

This is the detailed view

of a server in operation


23/25

A

STORAGE

SECTION

THIS IS THE AREA

WHERE THE DATA IS

STORED FOR ANYEXCHANGE.

THE TOTAL CAPACITY

IS ABOUT 40 TB.

IT COMPRISES OF

INDIVIDUAL HDDs OF

CAPACITY 300 GBs

EACH (SHOWN HERE

WITH WHITE LABELS).


24/25

References

DS-8000 Copy Services Environment (IBM Redbooks

Publications/ISBN-0738431141)

DS-8000 Architecture (IBM Redbooks Publications/ISBN-

0738435066)

DS-8000 Performance & Monitoring (IBM Redbooks

Publications/ISBN-0738432695)

Disaster Recovery Strategies (IBM Redbooks Publications/ISBN-

0738426504)

IBM AIX Enterprise Edition System Administration Guide (IBMRedbooks Publications/ISBN-0738432903)

Other sourcesThe Internet


25/25

THANK YOU

presentation on training project(4)

Documents