Highly Availability and Fault tolerancewith

Apache CloudStack

Different workloads

• Traditional/Enterprise workloads• Cloud workloads

Traditional vs Cloud era workload

Link AggregationStorage Multi-pathingVM Live Migration

Multi-tier Apps

VM Backup/Snapshots

Multi-site RedundancyChaos Monkey

Ephemeral Resources

Traditional Workload Distributed Cloud-era Workload

Expect failure. Design app for failure. Self-service failure handling

Think Amazon Web Services

Expect reliability. Back-up entire cloud. Admin controlled failure

handlingThink Server Virtualization 1.0

Workload reliability drives unique requirements

CloudStack

CloudStack Supports both Workloads

Software Defined Networks (e.g., Security Groups, EIP, ELB,...)

Cloud-Era Availability Zone

Server

Racks

Server

Racks

Server

Racks

Server

Racks

Server

Racks

Server

Racks

Server

Racks

Server

Racks

Elastic Block Storage

vCenter

ESXi Cluste

r

ESXi Cluste

r

ESXi Cluste

r

Enterprise Networking (e.g., VLAN)

Enterprise Storage (e.g., SAN)

Traditional Availability Zone

Problem Statement

• How to measure business continuance

• High availability• Fault tolerance• Disaster Recovery

• How to build application for clouds

• How does Apache CloudStack enable highly available and fault tolerant applications

Solution set

• Rich set of features in CloudStack to build highly available and fault tolerant applications

• VM high availability• Snapshotting VM and Volumes• Automated snapshotting and backup• Anti-affinity and user dispersing planners

• Auto-Scaling• VM health checks• Load balancing• Global Server Load balancing

VM operations

HA & FT with loadbalancing

Distribute applications geographically

• Regions• Availability zones• Object store

Masking instance failures

• Elastic IP address• Portable IP address

Network service SPOF

• Redundant virtual Router

TENANT-A.cloud.xyztelco.com

CloudStack

Region-West

West-Zone 1 datacenter

Before CloudStack 4.2

Tenant A network

VM1 VM2

Load Balancer

X

TENANT-A.cloud.xyztelco.com

CloudStack

Region-West

West-Zone 1 datacenter

What if the whole zone goes down?

Tenant A network

VM1 VM2

Load Balancer

Users

West-Zone 1 Data Center

West-Zone-2 Data Center

GSLB

Object Store

Enablers for DR and Multi-Site Redundancy

Portable IP

Portable IP

Availability Zone

Availability Zone

Availability Zone

Object Storage

Cloud-Era Cloud

CloudStackMgmt. Server • Workloads are distributed across

availability zones• No guarantee on zone reliability• Applications designed to handle node level failure

• DBs and Templates snapped to object store.

• In event of failure, images are recreated on new availability zone.

• Dramatically less expensive

Designing a zone for an Cloud workload

• User acquires Portable IP to communicate externally as well as protect against (zone) failures

• Routing element sends a RHI (route health injection) to the upstream router to inject a route to PortableIP via OSPF or BGP

• Incoming traffic is directed to LB with PorableIP

• On Zone failure, PortableIP can be (via API or UI) transferred to another zone

• Routing in the new zone sends a RHI to the upstream router

• Traffic is directed to new LB with Portable IP

abc.xloud.xytelco.com

CloudStack

Region-West

West-Zone 1

Core RouterXYZTelco

VM2 VM1

Private IP10.1.1.12

LB1

PortableIP Across Zones

L3 Router

West-Zone 2

LB2

L3 RouterXPortable IP8.1.1.11

OSPF / BGP 8.1.1.11 LB1 Cost: 1

VM3 VM4

Private IP10.1.2.12

Basic failover architecture using Portable IP and ObjectStore

abc.xloud.xytelco.com

CloudStack

Region-West

West-Zone 1

websiteXYZTelco

MasterDB

WebServer1

Portable IP8.1.1.12

WebServer2

Portable IP8.1.1.11

SlaveDB MasterDB

WebServer1 WebServer2

SlaveDB

Object Store Object Store

Portable IP8.1.1.11

Portable IP8.1.1.12

West-Zone 2

Intermediate failover architecture using Portable IP and ObjectStore

abc.xloud.xytelco.com

CloudStack

Region-West

West-Zone 1

websiteXYZTelco

MasterDB

WebServer1

Portable IP8.1.1.12

WebServer2

Portable IP8.1.1.11

SlaveDB

WebServer3

Object Store

Portable IP8.1.1.13

West-Zone 2

Advanced failover architecture using Portable IP, ObjectStore & GSLB

Public DNSTENANT-A.cloud.xyztelco.com TENANT-B.cloud.xyztelco.com

CloudStack

Region-West

West-Zone 1 datacenter West-Zone 2 datacenter

Private DNScloud.xyztelco.com

<-TENANTB.cloud.xyztelco.com ADNS LB1 or ADNS LB2

XYZTelco cloud

DR as a Service with NetScaler

Object Store

Tenant A network

VM1 VM2

Tenant B network

VM3 VM4

Tenant A network

VM5 VM6

Tenant B network

VM7 VM8

MEPNetScalerADNS LB1

TENANTA.cloud.xyztelco.com ADNS LB1 or ADNS LB2

NetScalerADNS LB2

Thank you