Microsoft reached the RTM (Release To Manufacturing) milestone for Exchange Server 2010 on October 8, 2009, and was officially launched on November 9, 2009;.[18] A 120 day trial is downloadable from Microsoft.[17] Exchange Server 2010 is available in two server editions; Standard edition and Enterprise edition.
Major changes from previous versions of Exchange Server include:
Exchange's clustering (active-active or active-passive mode) has been criticized because of its requirement for servers in the cluster nodes to share the same physical data. The clustering in Exchange Server provides redundancy for Exchange Server as an application, but not for Exchange data.[20] In this scenario, the data can be regarded as a single point of failure, despite Microsoft's description of this set up as a "Shared Nothing" model.[21] This void has however been filled by ISV's and storage manufacturers, through "site resilience" solutions, such as geo-clustering and asynchronous data replication.[22] Exchange Server 2007 introduces new cluster terminology and configurations that address the shortcomings of the previous "shared data model".[23]
Exchange Server 2007 provides built-in support for asynchronous replication modeled on SQL Server's "Log shipping"[24] in CCR (Cluster Continuous Replication)[25] clusters, which are built on MSCS MNS (Microsoft Cluster Service—Majority Node Set) clusters, which do not require shared storage. This type of cluster can be inexpensive and deployed in one, or "stretched" across two datacenters for protection against site-wide failures such as natural disasters. The limitation of CCR clusters is the ability to have only two nodes and the third node known as "voter node" or file share witness[26] that prevents "split brain"[26] scenarios, generally hosted as a file share on a Hub Transport Server.[27] The second type of cluster is the traditional clustering that was available in previous versions, and is now being referred to as SCC (Single Copy Cluster). In Exchange Server 2007 deployment of both CCR and SCC clusters has been simplified and improved; the entire cluster install process takes place during Exchange Server installation. LCR or Local Continuous Replication[27] has been referred to as the "poor man's cluster". It is designed to allow for data replication to an alternative drive attached to the same system and is intended to provide protection against local storage failures. It does not protect against the case where the server itself fails.
In November 2007, Microsoft released SP1 for Exchange Server 2007. This service pack includes an additional high-availability feature called SCR (Standby Continuous Replication). Unlike CCR which requires that both servers belong to a Windows cluster, typically residing in the same datacenter, SCR can replicate data to a non-clustered server, located in a separate datacenter.
With Exchange Server 2010, Microsoft introduced the concept of the Database Availability Group (DAG). A DAG contains Mailbox servers that become members of the DAG. Once a Mailbox server is a member of a DAG, the Mailbox Databases on that server can be copied to other members of the DAG. When you add a Mailbox server to a DAG, the Failover Clustering Windows role is installed on the server and all required clustering resources are created.
Mac users wishing to access Exchange e-mail running on Exchange Server 2000 or 2003 must use Microsoft's Entourage client versions X, 2004 or 2008. Alternatively a limited version of Outlook Web Access is available to Mac users using a web browser. Entourage X, 2004 and 2008 do not support synchronizing tasks and notes with Exchange Servers 2000, 2003, 2007 or 2010. However Entourage 2008 "Web Services Edition", which is a free download from Microsoft for users of Office 2008, does support synchronizing tasks and notes with Exchange Server 2007 SP1 rollup update 4 or later (including Exchange 2010).
E-mail hosted on an Exchange Server can also be accessed using SMTP, POP3 and IMAP4 protocols, using clients such as Outlook Express, Mozilla Thunderbird, and Lotus Notes. (These protocols must be enabled on the server. Recent versions of Exchange Server turn them off by default.)
Exchange Server mailboxes can also be accessed through a web browser, using Outlook Web Access (OWA). Exchange Server 2003 also featured a version of OWA for mobile devices, called Outlook Mobile Access (OMA).
DavMail Gateway allows any email client to connect to a Microsoft Outlook server with Outlook Web Access (OWA).
GNOME Evolution project can be used to Connect to MS-Exchange (in OWA mode for Exchange 2000/2003, native mode for Exchange 2007).[30] Evolution is now also available for Windows.[31][32]
Major changes from previous versions of Exchange Server include:
- The high availability options for Mailbox Databases (SCC: Single Copy Clustering, CCR: Clustered Continuous Replication and LCR: Local Continuous Replication) and site resiliency functionality (SCR: Standby Continuous Replication) have been replaced by Database Availability Groups (DAGs) in Exchange Server 2010. Major DAG benefits include providing database level high availability (as opposed to server level), support for up to sixteen (16) copies of each database, and flexible configuration (databases copies may be added / removed at will without requiring major server reconfiguration). Each server that runs the Enterprise edition of Exchange Server 2010 can host up to 100 database copies.
- High availability for the Client Access Server role in Exchange Server 2010 is provided by using Client Access Server (CAS) arrays. A CAS array can contain multiple Client Access Servers in an Active Directory site and provide a single name endpoint for client connections. CAS arrays cannot span multiple Active Directory sites.
- In Exchange Server 2007, a clustered mailbox server could not be combined with any other roles. In Exchange Server 2010, the Mailbox Server Role may be combined with the Client Access Server and/or Hub Transport roles, regardless of whether or not the mailbox server participates in a Database Availability Group. (However, since Database Availability Groups utilize Windows Failover Clustering, and Microsoft does not support the combination of Windows Failover Clustering and Windows Network Load Balancing on the same server, a multi-role deployment will require the use of a 3rd party load balancer to provide load balancing and fault tolerance for the Client Access Server role).
- With the introduction of the RPC Client Access service, all Outlook clients access their mailbox database through the Client Access Server role. This abstraction layer allows for improved load balancing and redundancy and minimal client impact in the event of a database level *-over ("switchover" or "failover") event.
- Exchange Server 2010 provides cost savings in required hardware. Storage performance requirements (measured in IOPS: Input/Output operations Per Second) have been reduced by approximately 70% over Exchange Server 2007, and by approximately 90% over Exchange Server 2003. According to a case study, Microsoft IT was able to reduce hardware costs by 75% during the migration from Exchange Server 2007 to Exchange Server 2010.
- Exchange Server 2010 extends the large mailbox support introduced in Exchange Server 2007, and also introduces a Personal Archive feature to allow messages to be retained longer without the need for a 3rd party archival system. The Personal Archive is implemented as a secondary mailbox for archive-enabled users, and in Exchange Server 2010 Service Pack 1, the Personal Archive may be located on a different database than the primary mailbox, which may reside on a different disk if desired.
- The compliance and legal search features have been enhanced. What was formerly known as the "Dumpster" in previous versions of Exchange (a special storage area for messages which have been deleted from the Deleted Items folder or "permanently deleted" from a regular folder, such as the Inbox) has been evolved into the Recoverable Items folder in Exchange Server 2010. If configured appropriately, the Recoverable Items folder allows for a "tamper proof" storage area (users cannot circumvent the Recoverable Items folder to bypass legal discovery), which also provides a revision history of any modified items.
- Administration delegation can now be performed at a granular level due to Exchange Server 2010's implementation of Role Based Access Control (RBAC). Users and administrators can be given extremely fine grained abilities for functions provided both within the Exchange Management Console or Exchange Management Shell and in Outlook Web App. For example, a compliance officer may be given the ability to perform cross mailbox discovery searches within Outlook Web App; a help desk technician may be granted the ability to set an Out Of Office message for other employees within the company, or a branch administrator in a remote office may be granted the permission to perform specific Exchange Management Shell commands that pertain only to the Exchange server in their branch office.
- Outlook Web App includes improvements (including, for example, the ability for users to track their sent messages and printable calendar views) and the "Premium" experience is now available across multiple browsers (including Safari and Firefox).
- Distribution groups can now be "moderated", meaning that distribution groups can now be configured to allow users to join at will or only with a group moderator's permission, and individual messages sent to distribution groups can now be approved or denied by a moderator.
- Exchange Server 2010 introduces a transport concept called "Shadow Redundancy" which protects e-mail messages while they are in transit. If a Hub Transport server or an Edge Transport server fails after it has received a message for processing, but before it was able to deliver it to the next "hop" server, the server which sent the message to that transport server is now able to detect the failure and redeliver the message to a different Hub Transport or Edge Transport server for processing.
[edit] Clustering and high availability
Exchange Server Enterprise Edition supports clustering of up to 4 nodes when using Windows 2000 Server, and up to 8 nodes with Windows Server 2003. Exchange Server 2003 also introduced active-active clustering, but for two-node clusters only. In this setup, both servers in the cluster are allowed to be active simultaneously. This is opposed to Exchange's more common active-passive mode in which the failover servers in any cluster node cannot be used at all while their corresponding home servers are active. They must wait, inactive, for the home servers in the node to fail. Subsequent performance issues with active-active mode have led Microsoft to recommend that it should no longer be used.[19] In fact, support for active-active mode clustering has been discontinued with Exchange Server 2007.Exchange's clustering (active-active or active-passive mode) has been criticized because of its requirement for servers in the cluster nodes to share the same physical data. The clustering in Exchange Server provides redundancy for Exchange Server as an application, but not for Exchange data.[20] In this scenario, the data can be regarded as a single point of failure, despite Microsoft's description of this set up as a "Shared Nothing" model.[21] This void has however been filled by ISV's and storage manufacturers, through "site resilience" solutions, such as geo-clustering and asynchronous data replication.[22] Exchange Server 2007 introduces new cluster terminology and configurations that address the shortcomings of the previous "shared data model".[23]
Exchange Server 2007 provides built-in support for asynchronous replication modeled on SQL Server's "Log shipping"[24] in CCR (Cluster Continuous Replication)[25] clusters, which are built on MSCS MNS (Microsoft Cluster Service—Majority Node Set) clusters, which do not require shared storage. This type of cluster can be inexpensive and deployed in one, or "stretched" across two datacenters for protection against site-wide failures such as natural disasters. The limitation of CCR clusters is the ability to have only two nodes and the third node known as "voter node" or file share witness[26] that prevents "split brain"[26] scenarios, generally hosted as a file share on a Hub Transport Server.[27] The second type of cluster is the traditional clustering that was available in previous versions, and is now being referred to as SCC (Single Copy Cluster). In Exchange Server 2007 deployment of both CCR and SCC clusters has been simplified and improved; the entire cluster install process takes place during Exchange Server installation. LCR or Local Continuous Replication[27] has been referred to as the "poor man's cluster". It is designed to allow for data replication to an alternative drive attached to the same system and is intended to provide protection against local storage failures. It does not protect against the case where the server itself fails.
In November 2007, Microsoft released SP1 for Exchange Server 2007. This service pack includes an additional high-availability feature called SCR (Standby Continuous Replication). Unlike CCR which requires that both servers belong to a Windows cluster, typically residing in the same datacenter, SCR can replicate data to a non-clustered server, located in a separate datacenter.
With Exchange Server 2010, Microsoft introduced the concept of the Database Availability Group (DAG). A DAG contains Mailbox servers that become members of the DAG. Once a Mailbox server is a member of a DAG, the Mailbox Databases on that server can be copied to other members of the DAG. When you add a Mailbox server to a DAG, the Failover Clustering Windows role is installed on the server and all required clustering resources are created.
[edit] Licensing
Like Windows Server products, Exchange Server requires Client Access Licenses, which are different from Windows CALs. Corporate license agreements, such as the Enterprise Agreement, or EA, include Exchange Server CALs. It also comes as part of the Core CAL. Just like Windows Server and other server products from Microsoft, you can choose to use User or Device CALs. Device CALs are assigned to a device (workstation, laptop or PDA). User CALs, are assigned to a user or employee (not a mailbox). User CALs allow a user to access Exchange e-mail from any device. User and Device CALs are the same price, however cannot be used interchangeably. For Service Providers looking to host Microsoft Exchange, there is an SPLA (Service Provider License Agreement) available whereby Microsoft receives a monthly service fee in the place of the traditional Client Access Licenses. Two types of Exchange CAL are available: Exchange CAL Standard and Exchange CAL Enterprise. The Enterprise CAL is an add-on license to the Standard CAL.[edit] Exchange Hosting
Microsoft Exchange Server can also be purchased as a hosted service from a number of providers.[28][edit] Clients
Microsoft Exchange Server uses a proprietary RPC protocol, MAPI/RPC,[29] that was designed to be used by the Microsoft Outlook client. Clients capable of using the proprietary features of Exchange Server include Microsoft Outlook and Novell Evolution. Exchange Web Services (EWS), an alternative to the MAPI protocol, is a documented SOAP based protocol introduced with Exchange Server 2007 which significantly reduces synchronization time between the server vs. WebDAV, which is used by Exchange Server 2003. Exchange Web Services is used by the latest version of Microsoft Entourage for Mac. Also, since the release of Mac OS X v10.6 (also known as Mac OS X Snow Leopard), Mac computers running OS X include some support for this technology via Apple's Mail application. Built-in support with Mac OS X 10.6 requires the Exchange organization to be running Exchange Server 2007 SP1/SP2 or Exchange Server 2010.Mac users wishing to access Exchange e-mail running on Exchange Server 2000 or 2003 must use Microsoft's Entourage client versions X, 2004 or 2008. Alternatively a limited version of Outlook Web Access is available to Mac users using a web browser. Entourage X, 2004 and 2008 do not support synchronizing tasks and notes with Exchange Servers 2000, 2003, 2007 or 2010. However Entourage 2008 "Web Services Edition", which is a free download from Microsoft for users of Office 2008, does support synchronizing tasks and notes with Exchange Server 2007 SP1 rollup update 4 or later (including Exchange 2010).
E-mail hosted on an Exchange Server can also be accessed using SMTP, POP3 and IMAP4 protocols, using clients such as Outlook Express, Mozilla Thunderbird, and Lotus Notes. (These protocols must be enabled on the server. Recent versions of Exchange Server turn them off by default.)
Exchange Server mailboxes can also be accessed through a web browser, using Outlook Web Access (OWA). Exchange Server 2003 also featured a version of OWA for mobile devices, called Outlook Mobile Access (OMA).
DavMail Gateway allows any email client to connect to a Microsoft Outlook server with Outlook Web Access (OWA).
GNOME Evolution project can be used to Connect to MS-Exchange (in OWA mode for Exchange 2000/2003, native mode for Exchange 2007).[30] Evolution is now also available for Windows.[31][32]
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