Virtualizing AsteriskVirtualizing Asterisk

Despairing Myths and LegendsNir Simionovich, Asterisk Guru

Greenfield Technologies Ltd.

A bit about myself�

• Founder of Greenfield Technologies Ltd

• Founder of the Israeli Asterisk Users • Founder of the Israeli Asterisk Users

group

• Started using Asterisk in 2002

• Author of the AsteriskNOW book from

Packt Publishing (Mar 08)Packt Publishing (Mar 08)

• Author of the Asterisk Developer’s Guide

book from Packt Publishing (Jan 09)

Asterisk – A SysAdmin’s POV

• When most SysAdmins look at Asterisk,

this is what they see:this is what they see:

Myth I: * is a resource hog

• Asterisk requires a fair amount of

resources in order to run properly.resources in order to run properly.

• The things that turn Asterisk into a

resource hog are the applications

associated with it (AGI, AMI and others).

• Call center applications usually consume • Call center applications usually consume

much resources.

Myth II: * is a slow dialer

• Traditional Asterisk based dialers utilize

the AMI interface for generating outbound the AMI interface for generating outbound

calls, in its most simplistic form.

• While AMI had progressed over the

years, traditional implementations are in

capable is surpassing the 10 calls per capable is surpassing the 10 calls per

second limitation.

• Companies build large infrastructures to

sustain their needs

Myth III: * Can’t run in a VM

• Myth III is a result of Myth I and Myth II

together.together.

• After all, if Asterisk is a hog, and,

• Asterisk is a slow dialer, thus,

• Running Asterisk in a VM based

environments is either complicated or environments is either complicated or

impossible.

Introducing PokeTalk.Com

Why is PokeTalk interesting?

• PokeTalk.Com is an ad driven, web

callback system based upon Asterisk.callback system based upon Asterisk.

• While it utilizes an Asterisk based dialer,

its platform is completely virtualized –

utilizing VMWARE Server.

• It currently operates 4 different Virtual • It currently operates 4 different Virtual

Asterisk servers, capable of sustaining

up to 100 dials per second and up to 800

concurrent channels.

How does it work?

The Architecture

Web ServerWeb Server

VMWARE

Server

VMWARE

Server

MySQL

Database

Cluster

Firewall

Asterisk Dialer

Asterisk Dialer

Web Server

Web Server

Asterisk Dialer

Asterisk Dialer

Web Server

Web Server

Firewall

ISP Web

LBS

Hardware Specification

• Each VMWARE server is based upon the

following hardware:following hardware:

– Intel Dual Quad Core XEON Processors

– 2 x RAID-1 SATA Drives (500GB)

– 2 x Gigabit Ethernet

– 16GB RAM– 16GB RAM

• In a VM environment, the more RAM you

have the better – even if you don’t use all

of it.

Guest Operating System Setup

• CentOS 5.2 64bit Release

• All services turned off• All services turned off

• Active services include SSH and xinetd

• VMWARE Server 1.0.4

• Each Virtual server is setup as:

– Dual Core CPU

– 2GB RAM

– 40GB Hard Drive (static allocation)

Dialer Operating System

• CentOS 5.2 32Bit Release

• Asterisk 1.4.22• Asterisk 1.4.22

• MySQL 5

• PHP 5.2

• lighttpd web server

• FreePBX Management Interface

• Dialer is implemented in PHP and C++!

The Dialer Application SetupSIP Termination Partners

Frontend Web

DialerHandler

Quaue Manager

XML-RPCXML-RPC Status

Reports

A few service facts (Jan 09)

• Number of registered users > 90,000

• Max number of concurrent calls across • Max number of concurrent calls across

the cluster: 360 calls

• Max number of concurrent requests

served: 110 concurrent requests

• Total number of minutes served monthly • Total number of minutes served monthly

> 2M minutes per month.

Why virtualize Asterisk?

• Enable better utilization of your hardware

moneymoney

• Consolidate your services into single

hardware infrastucture

• Utilizing Open/Free virtualization

technologies will lower your overall TCOtechnologies will lower your overall TCO

• Virtualizing Asterisk installations can

negate the need for multi-tennent

systems and IP centrex

Asterisk Clouding

• Currently, there are working installations

of Asterisk utilizing Amazon EC2of Asterisk utilizing Amazon EC2

• As a test, we’ve installed the dialer

application on EC2 based instances

• The added value of running virtual dialers

using EC2 is to get the dialer power you using EC2 is to get the dialer power you

need – when you need it and not more

• Performance during the test was identical

to that of VMWARE dedicated servers

Where to from here?

Development from the past�

• Today’s over excessive use of VM type run-

time environments do not fit well with time environments do not fit well with

virtualization

• Working with virtual servers require a return to

basics for most developers, returning to

paradigms of high-speed optimizations and low

memory foot printsmemory foot prints

• The more optimal your runtime is, the more

performance you’ll get from your virtual servers

environment

Optimize for -Optimize for -

Execute like -Execute like -

Pooled Provisioning

• Handling multiple VM images (or EC2 AMIs)

can be a hasslecan be a hassle

• Utilizing pooled provisioning and programmatic

API’s, your provisioning process can be

centralized and simple

• Maintain a single VM image instance (or EC2

AMI), and deploy your software from a central AMI), and deploy your software from a central

location

Yes We Can!Yes We Can!Yes We Can!Yes We Can!

Barak H. Obama Image taken from http://www.obamarama.org

Rules of thumb for Asterisk Virtualization

• Ensure proper coding techniques to

lower platform overheadslower platform overheads

• Utilize central pooling provisioning for

ease of management

• Make use of programmatic API’s in a

layered platform approachlayered platform approach

• Ensure proper caching in your

application

Questions?

• Contact Information:

– Nir Simionovich– Nir Simionovich

– (e) nirs@greenfieldtech.net

– (p) +972-73-2557799

– (w) http://www.simionovich.com

– (w) http://www.greenfieldtech.net– (w) http://www.greenfieldtech.net

– (w) http://www.asterisk.org.il

– (MSN) nirs@greenfieldtech.net