vSphere HA and vSphere Fault Tolerance Module 9

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

Importance Most organizations rely on computer-based services like email, 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.

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

Lesson 1: Introduction to vSphere HA

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

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

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.

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

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

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

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

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.

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

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.

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

Lesson 2: vSphere HA Architecture

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

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

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

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

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

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)

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

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

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

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

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.

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

Lesson 3: Configuring vSphere HA

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

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

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.

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.

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.

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

vSphere HA Settings: Virtual Machine Monitoring (2)

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.

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

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

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

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.

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.

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

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

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

Lesson 4: Introduction to vSphere Fault Tolerance

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

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

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

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

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

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

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

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

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

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

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

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

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.

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

Lesson 5: vSphere Replication and vSphere Data Protection

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

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

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

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

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

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

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

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

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

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.

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

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?