1. vSphere HA and vSphere Fault Tolerance
Module 9

2. You Are Here Course Introduction Software-Defined Data Center
Creating Virtual Machines
vCenter Server
Configuring and Managing Virtual Networks
Configuring and Managing Virtual Storage
Virtual Machine Management
Resource Management and Monitoring
vSphere HA and vSphere Fault Tolerance
Host Scalability
vSphere Update Manager and Host Maintenance
Installing vSphere Components

3. Importance
Most organizations rely on computer-based services like , databases, and Web-based applications. The failure of any of these services can mean lost productivity and revenue. Configuring highly available, computer-based services is extremely important for an organization to remain competitive in contemporary business environments.

4. Module Lessons
Lesson 1: Introduction to vSphere HA Lesson 2: vSphere HA Architecture Lesson 3: Configuring vSphere HA Lesson 4: Introduction to vSphere Fault Tolerance Lesson 5: vSphere Replication and vSphere Data Protection

5. Lesson 1: Introduction to vSphere HA

6. Learner Objectives
By the end of this lesson, you should be able to meet the following objectives:
Describe the options that you can configure to make your VMware vSphere® environment highly available
Discuss the response of VMware vSphere® High Availability when a VMware ESXi™ host, a virtual machine, or an application fails

7. Protection at Every Level
vSphere makes it possible to reduce planned downtime, prevent unplanned downtime, and recover rapidly from outages.
vSphere 6 VM
vSphere HA and vSphere Fault Tolerance
vSphere Storage vMotion
Site Recovery Manager
vSphere vMotion, vSphere DRS
VMFS
NIC Teaming, Storage Multipathing
vSphere Replication, Third-Party Backup Solutions, vSphere Data Protection
Component
Server
Storage
Data
Site

8. vCenter Server Availability: Recommendations
Make VMware vCenter Server™ and the components that it relies on highly available.
vCenter Server relies on these major components:
vCenter Server database:
Create a cluster for the database.
Authentication identity source:
For example, VMware Center™ Single Sign-On™ and Active Directory.
Set up with multiple redundant servers.
Methods for making vCenter Server available:
Use vSphere HA to protect the vCenter Server virtual machine.

9. About vSphere HA
vSphere HA uses multiple ESXi hosts configured as a cluster to provide rapid recovery from outages and cost-effective high availability for applications running in virtual machines.
Protects against server failures
Protects against datastore accessibility failures
Protects against application failures
Protects virtual machines against network isolation

10. vSphere HA Scenarios: ESXi Host Failure
Virtual Machine A
Virtual Machine B
Virtual Machine C
Virtual Machine F
vCenter Server
ESXi Host
Virtual Machine D
Virtual Machine E
When a host fails, vSphere HA restarts the affected virtual machines on other hosts.
= vSphere HA Cluster

11. vSphere HA Scenarios: Guest Operating System Failure
Virtual Machine C
VMware Tools
VMware Tools
Virtual Machine E
When a virtual machine stops sending heartbeats or the virtual machine process crashes (vmx), vSphere HA resets the virtual machine.
VMware Tools
Virtual Machine A
VMware Tools
Virtual Machine B
VMware Tools
Virtual Machine D
VMware Tools
Virtual Machine F
ESXi Host
ESXi Host
ESXi Host
vCenter Server
= vSphere HA Cluster

12. vSphere HA Scenarios: Application Failure
Virtual Machine A
Application
Virtual Machine C
Application
Virtual Machine E
Application
When an application fails, vSphere HA restarts the affected virtual machine on the same host.
Requires installation of VMware Tools™.
Virtual Machine B
Application
Virtual Machine D
Application
Virtual Machine F
Application
ESXi Host
ESXi Host
ESXi Host
vCenter Server
= vSphere HA Cluster

13. Importance of Redundant Heartbeat Networks
In a vSphere HA cluster, heartbeats have these characteristics:
Heartbeats are sent between the master host and the slave hosts.
They are used to determine whether a master host or slave host has failed.
They are sent over a heartbeat network.
Redundant heartbeat networks ensure reliable failure detection.
Heartbeat network implementation:
Implemented by using a VMkernel port marked for management.

14. Redundancy Using NIC Teaming
You can use NIC teaming to create a redundant heartbeat network on ESXi hosts.
Ports or port groups used must be VMkernel ports.
NIC Teaming on an ESXi Host

15. Redundancy Using Additional Networks
You can also create redundancy by configuring more heartbeat networks: On each ESXi host, create a second VMkernel port on a separate virtual switch with its own physical adapter.

16. Review of Learner Objectives
You should be able to meet the following objectives:
Describe the options that you can configure to make your VMware vSphere® environment highly available
Discuss the response of VMware vSphere® High Availability when a VMware ESXi™ host, a virtual machine, or an application fails

17. Lesson 2: vSphere HA Architecture

18. Learner Objectives
By the end of this lesson, you should be able to meet the following objectives:
Describe the heartbeat mechanisms used by vSphere HA
Identify and discuss other failure scenarios
Recognize vSphere HA design considerations

19. vSphere HA Architecture: Agent Communication
Datastore
Datastore
Datastore
ESXi Host (Slave)
ESXi Host (Slave)
ESXi Host (Master)
FDM
FDM
FDM
vpxa
hostd
vpxa
hostd
vpxa
hostd
To configure high availability, ESXi hosts are grouped into an object called a cluster.
vpxd
vCenter Server
= Management Network

20. vSphere HA Architecture: Network Heartbeats
VMFS
VMFS
NAS/NFS
Virtual Machine A
Virtual Machine C
Virtual Machine E
Virtual Machine B
Virtual Machine D
Virtual Machine F
Slave Host
Slave Host
Master Host
The master host sends periodic heartbeats to the slave hosts so that the slave hosts know that the master host is alive.
vCenter Server
Management Network 1
Management Network 2

21. vSphere HA Architecture: Datastore Heartbeats
VMFS
VMFS
NAS/NFS
Datastores are used as a backup communication channel to detect virtual machine and host heartbeats.
Virtual Machine A
Virtual Machine C
Virtual Machine E
Virtual Machine B
Virtual Machine D
Virtual Machine F
Slave Host
Master Host
Slave Host
Cluster Edit Settings Window
vCenter Server
Management Network 1
Management Network 2

22. Additional vSphere HA Failure Scenarios
Slave host failure
Master host failure
Host isolation
Virtual machine storage failure:
Virtual Machine Component Protection
All Paths Down
Permanent Device Loss
Network failures and isolation

23. VMFS (Heartbeat Region)
Failed Slave Host
When a slave host does not respond to the network heartbeat issued by the master host, the master vSphere HA agent tries to identify the cause.
vCenter Server
Virtual Machine A
Virtual Machine B
Virtual Machine C
Virtual Machine D
Virtual Machine E
Virtual Machine F
Failed Slave Host
Master Host
Slave Host
NAS/NFS (Lock File)
File Locks
Primary Heartbeat Network
Alternate Heartbeat Network
VMFS (Heartbeat Region)

24. Failed Master Host
When the master host is placed in maintenance mode or crashes, the slave hosts detect that the master host is no longer issuing heartbeats.
Virtual Machine A
Virtual Machine B
Virtual Machine C
Virtual Machine D
Virtual Machine E
Virtual Machine F
Slave Host MOID: 98
File Locks
NAS/NFS (Lock File)
vCenter Server
Primary Heartbeat Network
Alternate Heartbeat Network
MOID = Managed Object ID
Default Gateway (Isolation Address)
Slave Host MOID: 100
VMFS (Heartbeat Region)
master host MOID: 99
Failed Master Host MOID: 99

25. Default Gateway (Isolation Address)
Isolated Host
If the host does not observe election traffic on the management and cannot ping its default gateway, the host is isolated.
Virtual Machine A
Virtual Machine C
Virtual Machine E
Virtual Machine B
Virtual Machine D
Virtual Machine F
ESXi Host
ESXi Host
ESXi Host
Default Gateway (Isolation Address)
Primary Heartbeat Network
Alternate Heartbeat Network

26. Design Considerations
Host isolation events can be minimized through good design:
Implement redundant heartbeat networks.
Implement redundant isolation addresses.
If host isolation events do occur, good design enables vSphere HA to determine whether the isolated host is still alive.
Implement datastores so that they are separated from the management network by using one or both of the following approaches:
Fibre Channel over fiber optic
Physically separating your IP storage network from the management network

27. Virtual Machine Storage Failures
With an increasing number of virtual machines and datastores on each host, storage connectivity issues have high costs but are infrequent.
Connectivity problems due to:
Network or switch failure
Array misconfiguration
Power outage
Virtual machine availability is affected:
Virtual machines on affected hosts are difficult to manage.
Applications with attached disks crash.
ESXi

28. Virtual Machine Component Protection
Virtual Machine Component Protection (VMCP) protects against storage failures in a virtual machine. Only vSphere HA clusters that contain ESXi 6 hosts can be used to enable VMCP.
Runs on cluster enabled for vSphere HA.
ESXi
Application availability and remediation.
VMCP detects and responds to failures.

29. Review of Learner Objectives
You should be able to meet the following objectives:
Describe the heartbeat mechanisms used by vSphere HA
Identify and discuss other failure scenarios
Recognize vSphere HA design considerations

30. Lesson 3: Configuring vSphere HA

31. Learner Objectives
By the end of this lesson, you should be able to meet the following objectives:
Recognize the prerequisites for creating and using a vSphere HA cluster
Configure a vSphere HA cluster

32. About Clusters
A cluster is a collection of ESXi hosts and their associated virtual machines, configured to share their resources. vCenter Server manages cluster resources like a single pool of resources. Components such as vSphere HA and VMware vSphere® Distributed Resource Scheduler™ are configured on a cluster.
Cluster

33. vSphere HA Prerequisites
All hosts must be licensed for vSphere HA.
A cluster must contain at least two hosts.
All hosts must be configured with static IP addresses. If you are using DHCP, you must ensure that the address for each host persists across reboots.
All hosts must have at least one management network in common.
All hosts must have access to the same virtual machine networks and datastores.
For Virtual Machine Monitoring to work, VMware Tools™ must be installed.
Only vSphere HA clusters that contain ESXi 6 hosts can be used to enable VMCP.

34. Configuring vSphere HA Settings
When you create a vSphere HA cluster or configure a cluster, you must configure settings that determine how the feature works.

35. Permanent Device Loss and All Paths Down Overview
vSphere HA uses VMCP to move virtual machines in Permanent Device Loss and All Paths Down situations to other fully connected hosts.
Permanent Device Loss:
The datastore appears as unavailable in the Storage view.
A storage adapter indicates the operational state as loss of communication.
All paths to the device are marked as dead.
All Paths Down:
A storage adapter indicates the operational state as dead or error.
The vSphere Client is unable to connect directly to the ESXi host.
The ESXi host appears as disconnected in vCenter Server.

36. vSphere HA Settings: Virtual Machine Monitoring (1)
You use Virtual Machine Monitoring settings to control the monitoring of virtual machines.

37. vSphere HA Settings: Virtual Machine Monitoring (2)

38. vSphere HA Settings: Datastore Heartbeating
A heartbeat file is created on the selected datastores and is used in the event of a management network failure.

39. vSphere HA Settings: Admission Control
vCenter Server uses admission control to ensure that:
Sufficient resources are available in a cluster to provide failover protection
Virtual machine resource reservations are respected

40. vSphere HA Settings: Advanced Options
To customize vSphere HA behavior, you set advanced vSphere HA options.
To force cluster not to use the default isolation address (default gateway):
das.usedefaultisolationaddress = false
To force cluster to ping alternate isolation addresses:
das.isolationaddressX = pintable address
To force cluster to wait beyond default 30-second isolation action window:
fdm.isolationpolicydelaysec = > 30 sec

41. Configuring Virtual Machine Overrides
You can override the vSphere HA settings that are set on a cluster for individual virtual machines in that cluster.

42. Network Configuration and Maintenance
Before changing the networking settings on an ESXi host (adding port groups, removing virtual switches, and so on), you must suspend the Host Monitoring feature and place the host in maintenance mode. This practice prevents unwanted attempts to fail over virtual machines.

43. Cluster Resource Reservation
The Resource Reservation tab reports total cluster CPU, memory, memory overhead, storage capacity, the capacity reserved by virtual machines, and how much capacity is still available.

44. Monitoring Cluster Status
You can monitor the status of a vSphere HA cluster on the Monitor tab.

45. Lab 21: Using vSphere HA Demonstrate vSphere HA functionality
Create a Cluster Enabled for vSphere HA
Add Your ESXi Host to a Cluster
Test vSphere HA Functionality
View the vSphere HA Cluster Resource Usage
Manage vSphere HA Slot Size
Configure a vSphere HA Cluster with Strict Admission Control
Prepare for Upcoming Labs

46. Review of Learner Objectives
You should be able to meet the following objectives:
Recognize the prerequisites for creating and using a vSphere HA cluster
Configure a vSphere HA cluster

47. Lesson 4: Introduction to vSphere Fault Tolerance

48. Learner Objectives
By the end of this lesson, you should be able to meet the following objectives:
List VMware vSphere® Fault Tolerance requirements and limitations
Describe vSphere Fault Tolerance operation

49. vSphere Fault Tolerance
vSphere Fault Tolerance provides instantaneous failover and continuous availability:
Zero downtime
Zero data loss
No loss of TCP connections
ESXi
Primary Virtual Machine
Secondary Virtual Machine
Instantaneous Failover
Fast Checkpointing

50. vSphere Fault Tolerance Features (1)
vSphere Fault Tolerance protects mission-critical, high-performance applications regardless of the operating system used.
vSphere Fault Tolerance:
Supports up to four virtual CPUs
Supports up to 64 GB of memory
Supports VMware vSphere® vMotion® for primary and secondary virtual machines
Creates a secondary copy of all virtual machine files, including disks
Provides fast checkpoint copying to keep primary and secondary CPUs synchronized

51. vSphere Fault Tolerance Features (2)
Supports thin-provisioned disks
Supports memory virtualization hardware assist
Supports Enhanced vMotion Compatibility clusters

52. How vSphere Fault Tolerance Works with vSphere HA and vSphere DRS
Is required for vSphere Fault Tolerance
Restarts failed virtual machines
Is vSphere Fault Tolerance aware
vSphere DRS:
Selects the virtual machine’s location at power-on
Does not balance fault-tolerant virtual machines in a balanced cluster
Primary
Machine
Secondary Machine
New Secondary Machine
ESXi
ESXi
ESXi

53. Redundant VMDKs
vSphere Fault Tolerance creates two complete virtual machines.
Each virtual machine has its own .vmx configuration file and .vmdk files. Each of these virtual machines can be on a different datastore.
Primary
Secondary
.vmx file
.vmx file
Datastore 1
Datastore 2
vmdk file
vmdk file
vmdk file
vmdk file
vmdk file
vmdk file

54. vSphere Fault Tolerance Checkpoint
vSphere Fault Tolerance supports multiple processors. Changes on the primary machine are not processed on the secondary machine. The memory is updated on the secondary.
Input
ESXi
ESXi FT
Network
Result X
Result X

55. vSphere vMotion: Precopy
During a vSphere vMotion migration, a second virtual machine is created on the destination host. Then the memory of the source virtual machine is copied to the destination.
VM A
VM A
Memory Bitmap
vSphere vMotion Network
Memory Precopy
Virtual Machine Port Group
Virtual Machine End User

56. vSphere vMotion: Memory Checkpoint
In vSphere vMotion migration, checkpoint data is the last bit of memory that keeps changing.
VM A
VM A
VM A
Memory Bitmap
vSphere vMotion Network
Checkpoint Data
Virtual Machine Port Group
Virtual Machine End User

57. vSphere Fault Tolerance Fast Checkpointing
The SMP FT checkpoint interval is dynamic by default. It adapts to maximize the workload performance and can range from as small as a few milliseconds to as large as several hundred milliseconds.
vmx config
Devices
Disks
VM memory
checkpoint
Primary Host
Secondary Host
Fault Tolerance
Network

58. Shared Files vSphere Fault Tolerance has shared files:
shared.vmft prevents UUID change.
.ftgeneration is for the split-brain condition.
Primary Host
Secondary Host
shared.vmft
.ftgeneration

59. shared.vmft File
The shared.vmft file, which is found on a shared datastore, is the vSphere Fault Tolerance metadata file and contains the primary and secondary instance UUIDs and the primary and secondary vmx paths.
UUID-1
UUID-1
UUID-2
VM Guest OS
Ref: UUID-1

60. Enabling vSphere Fault Tolerance on a Virtual Machine
You can turn on vSphere Fault Tolerance for a virtual machine through the VMware vSphere® Web Client.

61. Review of Learner Objectives
You should be able to meet the following objectives:
List VMware vSphere® Fault Tolerance requirements and limitations
Describe vSphere Fault Tolerance operation

62. Lesson 5: vSphere Replication and vSphere Data Protection

63. Learner Objectives
By the end of this lesson, you should be able to meet the following objectives:
Describe VMware vSphere® Replication™
Identify vSphere® Data Protection™ requirements
List vSphere Data Protection sizing guidelines
Describe vSphere Data Protection installation and configuration
Explain how to back up and restore data with vSphere Data Protection

64. About vSphere Replication
vSphere Replication is an extension to vCenter Server. It provides hypervisor-based virtual machine replication and recovery.
vSphere Replication
vSphere
Source
Target

65. vSphere Replication Appliance
The vSphere Replication appliance provides all the components required to perform vSphere replication.
vSphere Replication Appliance
Standard OVF Virtual Appliance
Delivered with the vSphere Platform
Included with Most vSphere Editions

66. How Replication Works
vSphere Replication enables replication of a virtual machine from a source site to a target site, monitoring and managing the status of the replication, and recovering the virtual machine at the target site.
Replication Between
Two Sites

67. Steps for Full Recovery
vSphere Replication integrates with Volume Shadow Copy Service through VMware Tools.
1. Right-click and select Recover.
2. Select a target folder.
3. Select a target resource.
4. Click Finish.
Validates your choices as you go

68. About vSphere Data Protection
vSphere Data Protection is a robust, easily deployed, disk-based backup and recovery solution.
vSphere Data Protection

69. vSphere Data Protection Requirements and Architecture
vSphere Data Protection requires vCenter Server, either the Windows implementation or vCenter Server™ Appliance™.
vSphere Data Protection Components

70. vSphere Data Protection Deployment and Configuration
vSphere Data Protection is deployed using vSphere Web Client from a prepackaged Open Virtualization Archive (OVA) file.
vSphere Data Protection: Configuring the UI to Run in Maintenance Mode

71. Creating and Editing a vSphere Data Protection Backup Job
You create and edit a backup job on the Backup tab of the vSphere Data Protection UI in the vSphere Web Client.
Creating a Custom Retention Policy

72. Performing Restores with vSphere Data Protection
You can restore an entire virtual machine from the Restore tab in the vSphere Data Protection UI:
The administrator can browse the list of protected virtual machines and select one or more restore points.
Individual VMDKs can also be restored.

73. Review of Learner Objectives
You should be able to meet the following objectives:
Describe VMware vSphere® Replication™
Identify vSphere® Data Protection™ requirements
List vSphere Data Protection sizing guidelines
Describe vSphere Data Protection installation and configuration
Explain how to back up and restore data with vSphere Data Protection

74. Key Points
vSphere HA restarts virtual machines on the remaining hosts in the cluster.
Hosts in vSphere HA clusters have a master-slave relationship.
You implement redundant heartbeat networks either with NIC teaming or by creating additional heartbeat networks.
vSphere Fault Tolerance provides zero downtime for applications that must be available at all times.
vSphere Replication can be used to protect virtual machines as part of a disaster recovery strategy.
vSphere Replication is the only hypervisor-based replication solution that operates at the individual VMDK level, enabling replication between datastores hosted on any storage.
vSphere Data Protection is a backup and recovery solution from VMware.
Questions?