Exchange Server 2013 Technology Primer (part 1) - What Is Exchange Server 2013?

Microsoft Exchange Server 2013 is the latest release of the messaging and communications system from Microsoft built on the Windows operating system.

1. What Is Exchange Server 2013?

At its core, Microsoft Exchange Server 2013 is an email, calendaring, and address book system that runs on a centralized Windows Server system. However, with the release of Exchange Server 2013, now the eighth major release of Exchange in the over 15-year history of the product, Microsoft has made significant improvements in the areas of global scalability, mobile and tablet client support, security, compliance, reliability, unified communications, and integration with SharePoint 2013 and Lync 2013.

So back to the basics of Exchange, with a centralized Exchange server holding mail messages, calendar appointments, contacts, and other user information, the Exchange environment provides a server-based storage of information. Users throughout the organization connect to the Exchange server from Microsoft Outlook, from a web browser, from a mobile phone or tablet system, or from a variety of other client systems to get access to their email and other information.

For larger organizations, multiple Exchange servers can be added to the environment hosting mailbox information of the users. Microsoft has split the roles of servers in an Exchange environment, where some servers are dedicated for antivirus and antispam filtering, and other servers are dedicated to client system connections throughout the organization.

Understanding the Evolution of Exchange

For those new to Microsoft Exchange, this section covers the history of the Exchange product line. Sometimes as a newcomer to a technology, it’s hard to jump right into the technology because everyone working with the technology refers to previous versions without taking into consideration that some people might not remember what was in the last revision, or in the product a couple of revisions back. So, this section is intended to give you a little history of Exchange so that the version numbers and major notable features and functions make sense.

Exchange Server 4.0

The first version of Microsoft Exchange, despite the 4.0 designation, was Exchange Server 4.0. Some people ask, “What happened to Exchange Server 1.0, 2.0, and 3.0?” For a bit of trivia, prior to Exchange Server 4.0, Microsoft had MS-Mail 3.0 (and MS-Mail 2.0); prior to that, it was a product called Network Courier Mail that Microsoft bought in the early 1990s.

Microsoft Exchange Server 4.0 had nothing in common with MS-Mail 3.0; they were completely different products and different technologies. The first rollouts of Exchange Server 4.0 back in 1996 were on Windows NT Server 3.51, which anyone with old NT 3.x experience knows was a challenging operating system to keep fully operational. “Blue screens” in which the operating system would just lock up were common. Anything that caused a system error usually resulted in a blue screen, which meant that every patch, update, service pack addition, installation of antivirus software, and so on frequently caused complete server failures.

However, Exchange Server 4.0 was a major breakthrough, and organizations started to migrate from MS-Mail (or at that time cc:Mail was another popular mail system) to Exchange Server 4.0. One of the biggest reasons organizations were migrating to Exchange Server 4.0 was that in 1996, the Internet was just opening up to the public. The specifications for the World Wide Web had just been released. Organizations were connecting systems to the Internet, and one of the first real applications that took advantage of the Internet was Microsoft Exchange Server 4.0. Organizations were able to connect their Exchange Server 4.0 server to the Internet and easily and simply send and receive emails to anyone else with an Internet-connected email system. MS-Mail 3.0 at the time had a Simple Mail Transfer Protocol (SMTP) gateway; however, it worked more on a scheduled dial-up basis, whereas Exchange Server 4.0 had a persistent connection to, typically, Integrated Services Digital Network (ISDN) or 56-KB frame connections to the Internet. And with Windows NT 4.0 shipping and being a much more solid infrastructure to work from, Exchange Server 4.0 was much more reliable than MS-Mail was for centralized organizationwide email communications.

Exchange Server 5.0

Exchange Server 5.0 came out in 1997 and was built to run on Windows NT 4.0, which proved to add more reliability to the Exchange Server product. In addition, Exchange Server 5.0 supported the first version of Outlook that to this day has a similar mailbox folder concept with the Inbox, Sent Items, Calendar, Contacts, and other common folders duplicated by mail systems throughout the industry. With the support for the Microsoft Outlook (97) client, Exchange also included calendaring directly within the Exchange product. In Exchange Server 5.0, the calendaring product was Schedule+, which was an add-on to Exchange Server 4.0, meaning that a user’s email and calendaring weren’t tied together, so Exchange Server 5.0 tied email, calendaring, and address books all together. With a service pack to Exchange Server 5.0, Microsoft also released the first version of Outlook Web Access (OWA) so that those who accessed the new World Wide Web could get remote access to their email on Exchange. Back in 1997, this was a big thing as web mail was a new concept, and Exchange Server 5.0 had web mail built in to the messaging product.

Exchange Server 5.0 also had better third-party support for things such as fax gateways, unified voice mail add-in products, and document-sharing tools, leveraging shared public folders in Exchange. With better reliability, third-party product support, and a growing base of customers now migrating from MS-Mail and cc:Mail to Exchange, the Microsoft Exchange market share started to skyrocket.

Exchange Server 5.5

In 1998, Microsoft released Exchange Server 5.5, which until just a few years ago some organizations were still running in their networking environments because of its reliability and stability as an email system. With Exchange Server 5.5, Microsoft worked out the bugs and quirks of their first two revisions of the Exchange product, and significantly better integration occurred between email, calendar, contacts, and tasks than in previous releases of Exchange. Microsoft also expanded the support for a larger Exchange database used to store messages. So instead of being limited to 16GB of mail with earlier releases of Exchange, organizations could upgrade to the Enterprise Edition of Exchange Server 5.5 that provided more than 16GB of data storage. With larger storage capabilities, Exchange Server 5.5 greatly supported large corporate, government, and organizational messaging environments.

Along with Exchange Server 5.5, OWA was improved to provide a faster and easier-to-use web client. The concept of site connectors was expanded with Exchange Server 5.5 to provide a larger enterprise Exchange environment with distribution of administration, message routing, and multilanguage support.

Exchange 2000 Server

Exchange 2000 Server came out in 2000 right after the release of Windows 2000 Server and the first version of Microsoft Active Directory (AD). The biggest change in Exchange 2000 Server is that it used Active Directory for the Global Address List (GAL), instead of Windows NT having its list of network logon users and Exchange Server 5.5 having its own directory of email users. Active Directory combined a network and email user account into one single account, making the administration and management of Exchange much simpler. Exchange 2000 Server also went to an ActiveX version of the OWA client instead of a straight Hypertext Markup Language (HTML) version of the web access, thus providing users with drag-and-drop capabilities, pull-down bars, and other functionality that made the web access function much easier for remote users.

Exchange 2000 Server, which is required to run on top of Windows 2000 Server, became much more reliable than Exchange Server 5.5, which ran on top of Windows NT 4.0. However, because Exchange Server 5.5 can run on top of Windows 2000 Server, many organizations made the shift to Exchange Server 5.5 on top of Windows 2000 Server. These organizations also gained better performance and reliability, which is why many organizations did not migrate from Exchange Server 5.5. However, Windows 2000 Server provided Exchange 2000 Server a stable operating system platform from the beginning. Also by 2000, Novell’s popularity was dramatically decreasing and organizations were migrating from Novell GroupWise to Exchange 2000 Server, so the Microsoft market share continued to grow.

Exchange Server 2003

Exchange Server 2003 was a major update to the Exchange messaging system that supported Active Directory. Although Exchange 2000 Server had Active Directory support, organizations found that Exchange Server 2003 on top of Active Directory 2003 provided a more reliable experience, better performance, and integration support between Exchange and AD. Exchange Server 2003 added mobility for users to synchronize their Pocket PC mobile devices to Exchange. In addition, OWA got yet another major face-lift mirroring the OWA interface with the normal Microsoft Office Outlook desktop client. With better remote support, Exchange Server 2003 became more than an office-based messaging system—it also greatly enhanced an organization’s ability to provide remote and mobile users with email anytime and anywhere.

Exchange Server 2003, running on top of Windows Server 2003, took advantage of additional operating system enhancements, making Exchange Server 2003 an even more reliable and manageable messaging system. Windows Server 2003 clustering finally worked so that organizations that put Exchange Server 2003 on top of Windows Server 2003 were able to do active-active and active-passive clustering. In addition, clustering went from two-node clusters to four-node clusters, providing even more redundancy and recoverability.

Exchange Server 2003 also introduced the concept of a recovery storage group (RSG) that allowed an organization to mount an Exchange database for test and recovery purposes. Prior to Exchange Server 2003, an Exchange database could only be mounted on an Exchange server, typically with the exact same server name and for the sole purpose of making the database accessible to users. The recovery storage group in Exchange Server 2003 allowed an Exchange database from another Exchange server to be mounted in an offline manner so that the Exchange administrator can extract corrupt or lost messages, or possibly even have the database in a “ready mode” to allow for faster recovery of a failed Exchange server.

Exchange Server 2003 Service Pack 2

Although not a major release of Exchange, it is significant to note a major service pack for Exchange Server 2003, which is Exchange Server 2003 Service Pack 2 (SP2). Exchange Server 2003 Service Pack 1 (SPI) introduced cyclic redundancy check (CRC) error checking of the Exchange database. For 10 years, information written to Exchange was done without error checking, so prior to 2005, Microsoft Exchange had a bad reputation for having corruption in its databases any time the databases got too large. Early Exchange administrators are likely familiar with the utilities EDBUtil and ISInteg that were used regularly to fix database corruption. Those utilities are, for the most part, not used anymore because error correction repairs are performed in real time to the Exchange databases. With the release of Exchange Server 2003 SP1, error checking brought Exchange to a whole new world in better reliability.

Exchange Server 2003 SP2 added to the reliability and security of Exchange by introducing support for SenderID message integrity checks as well as enhanced journaling of messages that captured a copy of messages in Exchange and locked the original copies of the messages in a tamperproof database that allowed for better support for regulatory compliance auditing and message integrity.

Exchange Server 2003 SP2 also added in direct push for mobile devices so that instead of having a Windows Mobile or Pocket PC device constantly “pull” messages down from Exchange, Exchange Server 2003 SP2 pushes messages to mobile devices, thus preventing constant polling by the mobile device, which increases battery life and enables Exchange and mobile devices to remain synchronized in real time.

Exchange Server 2007

Exchange Server 2007 was released in 2007 and changed the direction of Exchange in several ways. Exchange Server 2007 completely eliminated the concept of routing groups being separate from Active Directory sites. Prior to Exchange Server 2007, organizations would have both Active Directory sites and Exchange routing groups, and in most organizations they were identical and effectively required separate parallel configuration.

Exchange Server 2007 eliminated the separate routing group and instead looked to Active Directory’s sites and services to identify the subnets of various sites, and used the routing topology specified in Active Directory to move email along the same path and route as Active Directory replication.

Exchange Server 2007 also eliminated the Exchange Bridgehead server as a role that simply routed mail from Bridgehead server to Bridgehead server. The Bridgehead server evolved to the Hub Transport server in Exchange Server 2007 where every piece of email goes through. The Hub Transport server could be seen as a major central point of failure because every inbound, outbound, or even user-to-user email must pass through a Hub Transport server. However, because every piece of mail goes through the Hub Transport server, policies and rules can be set so that every email message can be filtered so that a single policy can be applied to not only Hub Transport to Hub Transport messages, but also even messages between users with mailboxes on the same Exchange server.

Outlook Web Access in Exchange Server 2007 was also dramatically improved being more than 95% feature complete with the full 32-bit version of Outlook. Web users have full control over mailbox rules and out-of-office rules, access to digitally rights managed content, and both provision and deprovision of their Windows Mobile devices within the OWA interface.

And finally, one of the major improvements in Exchange Server 2007 is the introduction of continuous replication, a major enhancement in mail system redundancy. Prior to Exchange Server 2007, a user’s mailbox was on only one server. If that server failed or if the database was corrupt, a third-party solution needed to be leveraged to minimize Exchange system outage. The most common method for fast database recovery was the use of storage area network (SAN) snapshots. Exchange Cluster Continuous Replication (CCR) provided organizations with a primary and secondary copy of the Exchange database. If the primary database failed, the secondary copy of the database automatically came online within 20–30 seconds, the user’s Outlook 2007 reconnected to the new server automatically, and the user never knew that the primary Exchange server had failed. And unlike many third-party solutions in the past that didn’t gracefully fail back to the primary server, Exchange Server 2007’s CCR failed back to the primary server just as it failed forward, providing organizations with a clean, high-availability solution.

Exchange Server 2007 Service Pack 1

Exchange Server 2007 Service Pack 1 was released late in 2007 and was seen by many as the first real version of Exchange Server 2007 with the addition of key components for the product version. Exchange Server 2007 SP1 enabled the access of public folders in OWA, something that many organizations could not upgrade to in the initial Exchange Server 2007 release because OWA users needed access to their public folders. Exchange Server 2007 SP1 also included Standby Continuous Replication (SCR) that provided a second-tier replication of Exchange databases. Where Exchange CCR provided a primary and secondary copy of the Exchange databases using instant failover clustering technology, SCR allowed for a replica of the Exchange databases to be created to a remote site with replication occurring in a 20-minute delayed manner. SCR provided organizations the capability to replicate information across a wide area network (WAN) to potentially an offsite data center.

Along the lines of high availability and disaster recovery came the concept of a stretched or geo-cluster in Exchange where Exchange Server 2007 SP1 could be installed on top of Windows Server 2008 that provided a geographically distributed cluster to split the Exchange CCR replicated data. With the Exchange CCR cluster split across a WAN link, if a primary server (and now site) failed, the secondary CCR cluster server would immediately become available for users to automatically reconnect to their mail. Stretch clusters for CCR provided not only high availability for mail, but also disaster recovery in a single solution.

Exchange Server 2010

Exchange Server 2010 is the most recent release of Exchange prior to the current Exchange Server 2013. Exchange Server 2010 took the technological enhancements introduced in Exchange Server 2007 and further extended the capabilities in terms of performance, reliability, and scalability. Most notable in Exchange Server 2010 was the introduction of database availability groups, or DAGs, for storage. Where Exchange Server 2007 introduced an online primary and secondary copy of mail across mailboxes with Cluster Continuous Replication, Exchange Server 2010 provided up to 16 copies of a user’s mailbox that could be situated on servers within a database or across multiple sites. With multiple copies of a user’s mailbox on multiple servers around the world, true high availability and disaster recovery has been achieved. High availability and redundancy has been so improved that many organizations no longer back up their Exchange servers as data is available and replicated for real-time redundancy.

Additionally with Exchange Server 2010, Outlook Web Access was not only renamed Outlook Web App to match the Office Apps concept, but closer feature parity between OWA and the traditional Outlook client was achieved. Users are able to access their email either through a full client or from a web client and be able to have full access to emails, calendars, contacts, mailbox rules, mobile phone management, and the like. Many organizations only provide Outlook through OWA when offline folders are not required, eliminating the need to deploy and support client software.

Behind the scenes to Exchange Server 2010 were also significant improvements in reliability such as the inclusion of a worker thread that defragmented the Exchange database as well as the ability for Exchange writes to be sequential to the Exchange database (instead of random writes to disk) that drastically improved overall performance for Exchange. With sequential reads of defragmented disks, Exchange Server 2010 performed 30% to 40% more efficiently for organizations, which allowed for greater density of users per Exchange server and virtually eliminated the concept of database maintenance that was a crux of Exchange in the first decade of its existence.

And by the year 2010, the use of mobile phones and tablet devices became common endpoint platforms with users desiring access from more than just a desktop or Web console. As such, Exchange Server 2010 provided full connectivity to Exchange from multiple endpoint platforms as well as voice prompt enabled Exchange so that a user could call into Exchange and navigate her mailbox, access calendar appointments, listen to messages that are text to speech converted for audio listening, and even have voice mail messages converted from voice to text for text-based viewing of voice messages.

Exchange Server 2010 integrated the world of voice mail, email, desktop access, and mobile access into the common platform.

While the list can go on with advancements made in Exchange Server 2010, to wrap up the content on Exchange Server 2010, the enhancements to email retention, archiving, and eDiscovery search were significant in Exchange Server 2010. Organizations were able to eliminate third-party archiving products and rely solely on Exchange Server 2010 for the long-term storage and compliance support for messaging. Users not only have primary mailboxes in Exchange, but also have email archives where data can be stored both from a data management perspective (eliminating the need for users to have multiple personal store (PST) files spread around with old mail messages stored) and also from the ability of the organization to implement and enforce data retention for legal compliance reasons. Exchange Server 2010 enabled eDiscovery of content stored in users’ mailboxes with the ability to query message content, extract messages, and put mailboxes on litigation hold to prevent users from purposely or accidentally deleting legal message evidence.

You’ll find Exchange Server 2013 extends all of these core enhancements introduced in Exchange Server 2010, further improving users’ experiences in their messaging, voice, content, and information management systems.

Office 365

Office 365 is Microsoft’s cloud-based Exchange Server, SharePoint, and Lync offering. As much as Office 365 is not in direct line with the Exchange on-premise offering, it is a parallel branch of Exchange Server worth noting. Office 365 was released in 2011 and provided organizations the option of setting up and implementing Exchange Server 2010 on-premise or pay a monthly fee for Exchange Server 2010 mailboxes hosted by Microsoft.

Through frequent updates of Office 365 by Microsoft, the cloud-based offering mirrored the features and capabilities of the on-premise Exchange Server. By early 2012, Microsoft releaseed a Hybrid mode of Office 365 that provided very tight integration between Exchange Online in the cloud and Exchange Server 2010 Service Pack 2 on-premise. Organizations were able to have users split between on-premise Exchange and Office 365 whether the hybrid was during a migration process, the hybrid was temporary during, for example, an acquisition of an organization, or the strategy of the organization to have core administration users access Exchange on-premise and field workers or temporary workers on Office 365.

Office 365 continues to evolve, and with Exchange Server 2013 again provides an onpremise Exchange Server 2013 environment as well as a cloud-based version of Exchange Server.

Exchange Server 2013 on 64-Bit Hardware

As with Exchange Server 2010, the Exchange Server 2013 product only comes in an x64-bit version. Exchange Server 2013 requires either Windows Server 2008 R2 or Windows Server 2012 (both x64-bit only operating systems) to run as the core operating system. Although Exchange Server 2013 requires Windows x64-bit to run the Exchange Server software, an organization can still run 32-bit Windows Server 2003 domain controllers and global catalog servers throughout the environment. Just the Exchange Server 2013 servers need to run x64-bit.

One of the biggest problems with earlier versions of Exchange on a 32-bit platform is the support for only 4GB of memory on an Exchange server. Just a few years ago, no one thought 4GB of RAM was a limitation. However, with Exchange and the amount of messaging transactions an organization can send and receive, what is required for an Exchange server to process far exceeded the memory space available in just 4GB of RAM. Because the processing of messages, write transactions to disk, logging for rollback recoverability, and the addition of spam and virus protection takes away from available memory in the system, 4GB would be used up quite quickly.

To compensate for the lack of available memory in 32-bit Exchange, Microsoft Exchange Server 2003 and prior depended heavily on caching transactions to disk. As an example, for an organization with 5,000 users on an Exchange Server 2003 server in a large enterprise, the Exchange Server 2003 server would have 4GB of RAM and need about 100GB of disk storage to have as available spool memory. In very large enterprises with tens of thousands of users, the Exchange servers could easily take up 500GB of disk space for spooling.

With 64-bit Windows and its support for 8TB of RAM memory, an Exchange Server 2013 server with 5,000 users now needs 32GB of RAM, but can do with just 5GB or less of spool disk space. Not only does the additional RAM eliminate the need for hundreds of gigabytes of spool disk space, the additional memory allows an Exchange Server 2013 server to support three to six times as many users per server, and provides a 50% to 80% increase in system efficiency of transactions.

Likewise, the 64-bit operating system also has proven to provide better support for significantly larger Exchange EDB databases. Most organizations wouldn’t think of having an Exchange 2000 Server or Exchange Server 2003 database greater than 80GB to 100GB in size; however, with a 64-bit operating system, Exchange Server 2013 supports databases that easily run in the hundreds of gigabyte and even multiple terabyte sizes.

This means that organizations need to make sure their server hardware is x64-bit. Most organizations have been buying x64-bit hardware for the past three to four years anyway because many hardware vendors stopped shipping 32-bit hardware years ago. The benefit of x64-bit hardware is that you can still run 32-bit software on the hardware until such time that you want to just install 64-bit software on the systems.

Note

Organizations with volume licensing agreements with Microsoft do not need to purchase or upgrade their Windows licenses from 32-bit to 64-bit. A Windows server license is a Windows server license, so regardless of whether the system is 32-bit or 64-bit, the organization’s server licenses remain the same.