Overview

General Overview

Contoso, Ltd. is an international company that has 3,000 employees. The company has sales, marketing, research, and human resource departments.

Physical Locations

Contoso has two main offices. The offices are located in New York and Chicago. Each office has a data center.

The New York office uses a network subnet of 10.1.0.0/16. The Chicago office uses a network subnet of 10.128.0.0/16.

The offices connect to each other by using a WAN link. Each office connects directly to the Internet.

Existing Environment

Active Directory

The network contains an Active Directory forest named contoso.com. The forest contains a single domain. All domain controllers run Windows Server 2012 R2. The forest functional level is Windows Server 2012 R2.

The forest contains six domain controllers configured as shown in the following table.

The forest is configured as a single Active Directory site.

Active Directory administrators manage the Active Directory schema. Exchange Server administrators do not have access to modify the schema.

Contoso has deployed Active Directory Rights Management Services (AD RMS).

Current Business Model

Contoso partners with a company names Fabrikam, Inc. on manufacturing initiatives. The partnership between Contoso and Fabrikam requires that both companies share confidential information frequently.

Requirements

Business Goals

Contoso plans to install Exchange Server 2016 to provide messaging services for its users.

It must be as easy as possible for the users at Contoso to share free/busy information with the users at Fabrikam.

As much as possible, Contoso plans to minimize the costs associated with purchasing hardware and software.

Planned Changes

Contoso plans to implement the following changes before installing Exchange Server 2016:

Install hardware Network Load Balancing (NLB) devices in the New York and Chicago offices.

Implement Microsoft Office Online Servers in the New York and Chicago offices.

Provide Contoso users with company-approved tablets.

Planned Messaging Infrastructure

You plan to create an Exchange Server 2016 organization named Contoso. You plan to deploy seven servers that will have Exchange Server 2016 installed. The servers will be configured as shown in the following table.

All of the servers will be members of a database availability group (DAG) named DAG01.

Client Access Requirements

Contoso identifies the following client access requ

irements for the planned deployment:

Users must be able to configure their tablet to synchronize email by using Autodiscover.

Users must be able to access the Exchange Server organization by using the following names:

Mail.contoso.com

Autodiscover.contoso.com

Users must be able to access Outlook on the web internally and externally from their tablet.

Users must be able to access Office Online Server by using the URL of office-online.contoso.com.

Security Requirements

Contoso identifies the following security requirements for the planned deployment:

Exchange Server mailbox databases must be encrypted while at rest.

Users must be prevented from using Outlook on the web while they are offline.

Contoso users must be able to share Calendar details with approved external domains only.

Email messages sent to the users in the fabrikam.com SMTP domain must be encrypted automatically.

Whenever possible, client computers must be directed to the same Exchange server for log collection.

Users must be able to access their mailbox by using Exchange ActiveSync on the company-approved tablets only.

Email messages sent from the users in the human resources department of Contoso must be protected by using AD RMS, regardless of the mail client.

Availability Requirements

Contoso identifies the following high-availability requirements for the planned deployment:

Servers must be able to complete a restart without administrative intervention.

The network load balancer must be able to probe the health of each workload.

If a data center fails, the databases in the other data center must be activated automatically.

Redundant copies of all email messages must exist in the transport pipeline before and after delivery.

Email messages must be made highly available by the Exchange Server organization before and after delivery.

If you manually mount the databases following the data center failure, the databases in the failed site must be prevented from mounting automatically.

You need to recommend a load balancing solution that meets the availability requirements.

Which load balancing solution should you recommend?

A. a Layer-7 load balancer with a single namespace and without session affinity

B. a Network Load Balancing (NLB) cluster

C. DNS round robin

D. a Layer-4 load balancer with multiple namespaces and without session affinity

From Scenario:

Contoso identifies the following high-availability requirements for the planned deployment:

The network load balancer must be able to probe the health of each workload.

Load balancers that work on the Layer 7 of OSI model are intelligent. Layer 7 load balancer is aware of the type of traffic passing through it. This type of load balancer can inspect the content of the traffic between the clients and the Exchange server. From this inspection, it gets that results and uses this information to make its forwarding decisions. For example, it can route traffic based on the virtual directory to which a client is trying to connect, such as /owa, /ecp or /mapi and it can use a different routing logic, depending on the URL the client is connecting to. When using a Layer 7 load balancer, you can also leverage the capabilities of Exchange Server 2016 Managed Availability feature. This built-in feature of Exchange monitors the critical components and services of Exchange server and based on results it can take actions.

Note: Layer 7 load balancer can use this to detect functionality of critical services, and based on that information decide if it will forward client connections to that node. If the load balancer health check receives a 200 status response from health check web page, then the service or protocol is up and running. If the load balancer receives a 403 status code, then it means that Managed Availability has marked that protocol instance down on the Mailbox server.

Although it might look that load balancer actually performs a simple health check against the server nodes in the pool, health check web page provides an information about workload-s health by taking into account multiple internal health check probes performed by Managed Availability.

Incorrect Answers:

D: Load balancers that work on Layer 4 are not aware of the actual traffic content being load balanced.

References: http://dizdarevic.ba/ddamirblog/?p=187