Microsoft Exchange Server Interview Questions & Answers Part 4

How can I see when Exchange last updated the OAB?

Get-OfflineAddressBook|FL LastTouchedTime

Extensible Storage Engine

The database engine Exchange Server uses is built on the ESE. The ESE exists in several flavors:

• ESE97 for Exchange Server 5.5
• ESE98 for Exchange Server 2000/2003
• ESENT for Active Directory
• ESE for Exchange Server 2007 and Exchange Server 2010

What is Transport Rules in Exchange Server 2013?

By using transport rules in Exchange 2013 we can filter, inspect or block any confidential emails that match any specific conditions with the email that matches the transport rule. By using this we would be able to prevent the leakage of the sensitive data in any organization.

Transport rules along with DLP and policy tips can be used to give end users warning informational tips when they try to send any emails which does not abide the company policy.

In-order to achieve this we need to create a transport rule first, and then create an associated DLP policy and then configure policy tips for the same.

Explain Accepted Domain and Remote Domain in Exchange Server 2013?

An Accepted Domain name is any SMTP namespace that your organization used to send and receive emails. Also the Accepted Domain includes the domains that are authoritative domain, internal relay or external relay domain.

Remote Domains are configured to control the settings of message transfer between your Exchange Organization and the remote domains. We control the settings like Message Format, Automatic Replies and NDR using the Remote domains

Categories /types of accepted domains in exchange 2013?

Authoritative Domain – It is the SMTP name space that is used by your Exchange Organization to send\receive emails

Internal Relay Domain – When an Exchange Organization is sharing the same address space with 3^rd party messaging or other exchange organization, the you need to create a internal relay domain, and you have to configure a Send Connector in Mailbox Server as the source with address space matches to the internal relay domain.
For example: If your company (A) and your partner company (B) is sharing the same SMTP namespace as @ab.com and your domain is authoritative to receive emails for Chennai.com. If an email sent for the user xyzr@ab.com first received by A and if the user mailbox is not there, then the email will be route to B organization using Send Connector

External Relay Domain – When you configure an external relay domain, messages are relayed to an email server that’s outside your Exchange organization and outside the organization’s network perimeter
By default the active directory domain name will be created as the default accepted domain for the Exchange Organization

Difference in replication of public folder in 2010 &2013 exchange DAG?

In Exchange2010, the public folders were not part of Database Availability Groups (DAGs) and used same PF replication method to achieve resilience and high availability. The drawback with this replication is that sometimes the user needs to wait for minutes to get the PF updated.

In Exchange 2013 the Public Folder is no longer a separate database. These are special mailboxes which store both the public folder hierarchy and the content and the replication uses continuous replication model. The PF is moving away from Multi-Master Replication Model to a Single-Master Replication Model of the Database Availability Groups (DAGs).

How Autodiscover works in exchange 2010 /2013?

1. Look in Active Directory to see if there is information about Exchange
2. Look at the root domain of the user’s email Address for configuration info
3. Look at autodiscover.emaildomain.com for configuration info
4. Look at the domain’s root DNS to see if any SRV records exist that point to a host that holds configuration info.

Note here that Outlook will only move from one step to the next if it doesn’t find configuration information.

For each step above, Outlook is looking for a specific file or a URL that points it to that file. The file in question is autodiscover.xml. By default, this is kept at https://<exchangeservername>/autodiscover/autodiscover.xml. Each step in the check process will try to find that file and if it’s not there, it moves on. If, by the end of step 4, Outlook finds nothing, you’ll get an error saying that an Encrypted Connection was unavailable, and you’ll probably start tearing your hair out in frustration.

How an internal, domain joined (which has Active Directory access) looks up the AutoDiscover record

1. Outlook opens, and queries Active Directory for the Service Connection Point on an Exchange server for the AutoDiscover URI / URL (I will explain more about this below)
2. Active Directory returns the URI / URL to the Outlook client, which then looks it up within DNS
3. Outlook connects to Exchange using the AutoDiscover URL over TCP 135 (RPC Endpoint Mapper) to Authenticate, pulls a ton of Exchange attributes from the mailbox (mainly find the mailbox using the homeMDB attribute along with the version of Exchange the user is on using the msExchangeVersion attribute), pulls the proper TCP ports (RPC Client Access, Address Book Service, Public Folders) and also pulls the Outlook provider record (e.g: EXPR: which gives the EWS InternalURL)
4. Outlook then negotiates its connection and connects into Exchange 

How an external, non-domain joined client (or domain joined clients who are out of the office) looks up AutoDiscover

1. Outlook will try to contact the local active directory domain but fails, thus falling back to URLs
2. Outlook will then attempt to query the https://domain.com/autodiscover/autodiscover.xml, but most likely fails. It falls back to http://domain.com/autodiscover/autodiscover.xml which will also most likely fail
3. Outlook then tries to connect using https://autodiscover.domain.com/autodiscover/autodiscover.xml, and if this fails it will try over HTTP using http://autodiscover.domain.com/autodiscover/autodiscover.xml
4. If this fails it will try to locate an SRV record for AutoDiscover (which I won't cover, since I rarely see them utilized in enterprise or medium-small business environments)
5. If everything fails it will most likely return a HTTP 500 error (service not found)

Eventually Autodiscover will connect over HTTPS if configured properly (e.g: SSL certificates and all) and also make its connection over Outlook Anywhere (RPC/HTTPS). Exchange will return the EXCH Outlook provider record that will contain the ExternalURL for EWS (for things such as Availability service, OOF, ect)

What is an email contact?

Mail contacts are mail-enabled directory service objects that contain information about people or organizations that exist outside your Exchange or Exchange Online organization. Each mail contact has an external email address

How to Monitor DAG

Test-ReplicationHealth –identity EXCHANGESERVERNAME1
Test-ReplicationHealth –identity EXCHANGESERVERNAME2
get-mailboxdatabasecopystatus *

Test-MapiConnectivity cmdlet to verify server functionality and database availability.

Only by monitoring and measuring performance across these three components can you be sure that your Database Availability Groups are actually delivering high availability.

How the flow of the mail is tracked in MS Exchange 2013?

To track message flow in MS Exchange 2013, Delivery Reports are used.  It is applicable for Outlook and Outlook web only.  However, Message Tracking Logs are also helpful to know the flow of the mail

Types of certificates used in Exchange?

Public CA, Internal CA or self-signed

• Wildcard certificates: These can be used for the entire domain and they are easy to spot because they have a format like *.domain.ca We can have unlimited hosts using that certificate on that domain. The drawbacks are that one single certificate is used for all your servers and in a larger company you do not want to have several departments with access to the same certificate, also they may bring some security concerns because their private key can be in several servers.
  In the past, they used to be more expensive than SAN Certificate but that is not the case anymore.
• SAN Certificates (Subject Alternative Names)
  This type of certificate allows more than a single name in a single SSL certificate which makes total sense for the new Microsoft products (Lync and Exchange) because several services are using names and all of them are underneath the same IIS Web Site. In some Public CA these certificates are also known as UC Certificates.

When do we need to configure Split brain DNS in AD with Exchange?

When our internal AD is running on private network using .local suffix. Then require configuration in the internal DNS by creating a mirror of the Public Zone in our internal network. This configuration is also known as split-brain DNS.

What is a Smart Host? Why we need to use it?

A smart host is a type of email message transfer agent that allows a Simple Mail Transfer Protocol (SMTP) server to route email to an intermediate mail server rather than directly to the recipient's server.

Where is Exchange Related info stored in Active Directory?

• Schema Partition: This contains a blueprint of all objects and properties in Active Directory. In a programming scenario, this would be called a class. When you create an object such as a user, it’s instantiated from the user blueprint in Active Directory.
• Configuration Partition: This contains information used throughout the forest. Regardless of the number of domains configured in Active Directory, all DCs use the same Configuration Partition in that particular Active Directory forest. As such, it’s replicated throughout the Active Directory forest. All changes to the Configuration Partition have to be replicated to all DCs. All Exchange Server 2010 information is stored in the Configuration Partition.
• Domain Partition: This contains information regarding the domains installed in Active Directory. Every domain has its own Domain Partition, so if there are 60 domains installed, there will be 60 different Domain Partitions. User information, including Mailbox information, is stored in the Domain Partition.