1 / 39

Exchange Server 2010 High Availability Design

UCC305. Exchange Server 2010 High Availability Design. Scott Schnoll scott.schnoll@microsoft.com Principal Technical Writer Microsoft Corporation. Agenda. Example designs Sizing Active Directory Namespaces Certificates User Distribution Models Storage Network

phyllis
Download Presentation

Exchange Server 2010 High Availability Design

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UCC305 Exchange Server 2010High Availability Design Scott Schnoll scott.schnoll@microsoft.com Principal Technical Writer Microsoft Corporation

  2. Agenda • Example designs • Sizing • Active Directory • Namespaces • Certificates • User Distribution Models • Storage • Network • Database Availability Group (DAG) Member Policies

  3. Exchange Server 2010 High Availability Design Principles: Example Designs

  4. DAG Design Examples • Two–member DAG • Smallest possible DAG that can provide high availability • Best-suited for small organizations that need high availability, but not site resilience • Enables redundancy of all roles with only two Exchange servers (can be Standard Edition of Exchange) • Will require third server (witness) • Will require non-WNLB solution

  5. DAG Design Examples • Four-member DAG (single site) • Provides greater availability than a 2 or 3-member DAG • Can deploy enough copies to • Use Exchange Native Data Protection • Use JBOD instead of RAID • Deploy lagged database copies

  6. DAG Design Examples • Seven-member, multi-site DAG • Provides greater availability by adding voting-only Mailbox servers • Because more voters are available, more servers can be lost while still maintaining quorum

  7. Exchange Server 2010 High Availability Design Principles: Sizing Database Availability Groups

  8. Sizing Database Availability Groups • The larger the DAG… • the better the resiliency, as larger DAGs continue to provide as much service as they can after more failures, based on the configuration • the better efficiency of the hardware, as you can more evenly distribute the active load across all members • For server count, consider a multiple of the number of database copies you are deploying • For example 3 copies and 3 or 6 servers, 4 copies and 4 or 8 servers, etc.

  9. Sizing Database Availability Groups • Question: How many DAGs should I deploy? • Answer: It depends • You will need to deploy multiple DAGs • If you need more than 16 servers • If you are deploying across multiple domains • If you need to separate administration of DAGs • You may also need multiple DAGs depending on your site resilience architecture

  10. Exchange Server 2010 High Availability Design Principles: Active Directory

  11. Active Directory • Follow Active Directory guidance for Active Directory site definition • http://aka.ms/nyd3h5 • Site assignment controls the association of Client Access and Hub Transport to Mailbox • CAS/HUB service local Mailbox servers, “mostly”

  12. Exchange Server 2010 High Availability Design Principles: Namespaces

  13. Namespaces • When planning for site resilience, each datacenter needs to be considered active • Exchange Server 2010 site resilience requires active Client Access and Hub Transport in each datacenter containing Mailbox server • These services are used by databases that undergo a cross-site *over

  14. Namespaces • Each datacenter is considered active • Each datacenter needs the following namespaces • OWA/OA/EWS/EAS namespace • POP/IMAP namespace • RPC Client Access Server Array namespace • SMTP namespace • One datacenter will maintain Autodiscover namespace • New in SP1 – FailbackURL namespace

  15. Namespaces • Use Split DNS for Exchange hostnames used by clients • Minimizes number of needed hostnames • mail.contoso.com for Exchange connectivity on intranet and Internet • mail.contoso.com has different IP addresses in intranet/Internet DNS

  16. Namespaces External DNS Mail.contoso.com Pop.contoso.com Imap.contoso.com Autodiscover.contoso.com Smtp.contoso.com External DNS Mail.sp.contoso.com Pop.sp.contoso.com Imap.sp.contoso.com Smtp.sp.contoso.com ExternalURL =mail.contoso.com CAS Array =outlook.contoso.com OA endpoint =mail.contoso.com ExternalURL = mail.sp.contoso.com CAS Array = outlook.sp.contoso.com OA endpoint = mail.sp.contoso.com Moscow St. Petersburg Internal DNS Mail.contoso.com Pop.contoso.com Imap.contoso.com Autodiscover.contoso.com Smtp.contoso.com Outlook.contoso.com Internal DNS Mail.sp.contoso.com Pop.sp.contoso.com Imap.sp.contoso.com Smtp.sp.contoso.com Outlook.sp.contoso.com HT CAS CAS HT AD MBX MBX AD

  17. Exchange Server 2010 High Availability Design Principles: Certificates

  18. Certificates • Minimize the number of certificates by using 1 certificate for • All Client Access, Edge Transport, Hub Transport and reverse proxy servers • Use Subject Alternative Name (SAN) certificate to cover multiple hostnames • If leveraging a certificate per datacenter, then ensure that the Certificate Principal Name is the same on all certificates • Outlook Anywhere won’t connect if the Principal Name on the certificate does not match the value configured in msstd: • Set-OutlookProvider EXPR -CertPrincipalNamemsstd:mail.contoso.com

  19. Exchange Server 2010 High Availability Design Principles: User Distribution Models

  20. User Distribution Models • Active/Passive user distribution model • Database copies deployed in the secondary datacenter, but no active mailboxes are hosted there • Active/Active user distribution model • User population dispersed across both datacenters with each datacenter being the primary datacenter for its specific user population

  21. Active/Active User Distribution

  22. Active/Active User Distribution

  23. Exchange Server 2010 High Availability Design Principles: RPC Client Access Server Array

  24. RPC Client Access Server Array • 1 RPC CAS Array per Active Directory site • RPC CAS Array does not provide any load balancing: you need a load balancer • FQDN of the RPC CAS Array must resolve internally to a load-balanced virtual IP address in DNS • RPCClientAccessServer is a property of Mailbox database • If database was created before array, then it is set to random CAS FQDN (or local machine if role co-location) • If database is created after array, then it is set to the array FQDN • Configure pre-existing databases to use RPC CAS Array • Set-MailboxDatabase -RPCClientAccessServer

  25. Exchange Server 2010 High Availability Design Principles: Storage

  26. Storage • Host each copy of a database on isolated storage • Deployment on RAID or JBOD will be based on several factors • Cost • Hardware • Number and type of copies • Datacenter topology

  27. Exchange Server 2010 High Availability Design Principles: Network

  28. Network • Complete redundancy is preferred but not required • Must have < 500 ms round-trip return latency between DAG members • Replication is always from source to target • If you have multiple passive copies in a remote datacenter, you will have multiple log streams from the active (one to each passive)

  29. Network • DAGs include compression for log shipping • Controllable setting for the DAG • Controlled at subnet level (default is inter-subnet) • MSIT sees 30% compression • Amount will vary for each customer based on message traffic • SP1 adds Continuous Replication Block Mode • Reduces the exposure of data loss on failure by replicating to passive copies all logs writes in parallel to them being locally persisted • Only active when replication is up-to-date in terms of copying complete logs

  30. Network • If using iSCSI storage, configure DAG and cluster to ignore iSCSI networks • Set-DatabaseAvailabilityGroupNetwork -Identity <DAG Network Name> -ReplicationEnabled:$false -IgnoreNetwork:$true • Block cross-network communication to minimize heartbeat traffic Allowed Subnet 1 Subnet 3 M M M M R R R R Subnet 2 Subnet 4 Blocked

  31. Exchange Server 2010 High Availability Design Principles: DAG Member Policies

  32. Policies • Database Copy Automatic Activation Policy • Configured with Set-MailboxServer • Blocked – no automatic activation • IntrasiteOnly – activation within site only; blocks cross-site failover • Unrestricted – normal mode, no restrictions

  33. Policies • Maximum Active Databases • Configured with Set-MailboxServer • Whole number value that specifies the maximum number of active database copies on the server • Once maximum is reached, no other databases can be activated on server

  34. Related Content • UCC402 - Exchange 2010 High Availability Deep Dive

  35. Resources • Exchange Team Blog • http://aka.ms/EHLO • Exchange 2010 Documentation Library • http://aka.ms/Ex2010Docs

  36. Feedback Your feedback is very important! Please complete an evaluation form! Thank you!

  37. Questions? • UCC305 • Scott Schnoll • Principal Technical Writer • scott.schnoll@microsoft.com • http://blogs.technet.com/scottschnoll • Twitter: @schnoll • You can ask me questions at the “Ask the Expert” zone: • November 10, 2011 12:30 – 13:30

More Related