Post on 13-May-2015
SQL Server 2000 ClusteringSQL Server 2000 Clustering
Jeff DaltonJeff Dalton
Extreme LogicExtreme Logic
January 8, 2003January 8, 2003
AgendaAgenda Why ClusterWhy Cluster Cluster ConceptsCluster Concepts Windows 2000 Cluster TechnologyWindows 2000 Cluster Technology SQL Server 2000 Cluster TechnologySQL Server 2000 Cluster Technology Failover Cluster in ActionFailover Cluster in Action Best Practices and ResourcesBest Practices and Resources
Improve Operational ExcellenceImprove Operational Excellence
How much downtime can my company afford How much downtime can my company afford without losing productivity, profits, sales, without losing productivity, profits, sales, etc.?etc.?
The goal of a highly available system is to The goal of a highly available system is to provide continuous use of critical data and provide continuous use of critical data and applications regardless of applications regardless of plannedplanned and and unplannedunplanned interruption interruption
Infamous “Five 9s”Infamous “Five 9s” How available is available and how much will How available is available and how much will
it cost?it cost? Knowing the business need will help determine Knowing the business need will help determine
technology coststechnology costs The more you need, the more you will need to The more you need, the more you will need to
spendspend
Failover Clusters; part of the Failover Clusters; part of the solution!solution!
Clusters DefinedClusters Defined A cluster is a A cluster is a groupgroup of independent of independent
computers (computers (nodesnodes) that work together to run ) that work together to run a common set of applications and provide a common set of applications and provide the image of a the image of a single systemsingle system ( (virtual servervirtual server) ) to the client and application. The computers to the client and application. The computers are are physically connectedphysically connected by cables and by cables and programmatically connectedprogrammatically connected by cluster by cluster softwaresoftware
Two different cluster models in the industry:Two different cluster models in the industry: Shared NothingShared Nothing (the Microsoft Way) (the Microsoft Way)
Only one node can own and access a single Only one node can own and access a single hardware resource at any timehardware resource at any time
Shared DeviceShared Device Any node can access any hardware resource in Any node can access any hardware resource in
the cluster as the Distributed Lock Manager the cluster as the Distributed Lock Manager ((DLMDLM) arbitrates access) arbitrates access
Windows 2000 Clustering Windows 2000 Clustering TechnologiesTechnologies
Server ClusterServer Cluster Intended primarily as a Intended primarily as a high availabilityhigh availability
technology to provide failover support for technology to provide failover support for applications such as applications such as databasesdatabases (SQL Server 2000), (SQL Server 2000), messaging systems and file/print servicesmessaging systems and file/print services
2-node FAILOVER CLUSTERS in Advanced Server 2-node FAILOVER CLUSTERS in Advanced Server and 4-node in Datacenter Serverand 4-node in Datacenter Server
Primary focus of our talk !Primary focus of our talk ! Network Load Balancing (NLB) ClusterNetwork Load Balancing (NLB) Cluster
Load balances incoming IP traffic across clusters Load balances incoming IP traffic across clusters of up to 32 nodesof up to 32 nodes
Enhances both availability and Enhances both availability and scalabilityscalability of of Internet server-based programs such as Web Internet server-based programs such as Web Servers Servers
Benefits of Windows 2000 Benefits of Windows 2000 ClusteringClustering
High Availability (think Server Cluster)High Availability (think Server Cluster) Designed to avoid Single Point of Failure (SPoF)Designed to avoid Single Point of Failure (SPoF) Ability of an application to continue operation Ability of an application to continue operation
with loss of single componentwith loss of single component Ownership of resources automatically transferred Ownership of resources automatically transferred
to surviving server; users experience only a to surviving server; users experience only a momentary pause in servicemomentary pause in service
Scalability (think NLB Cluster)Scalability (think NLB Cluster) Ability of an application to grow in size as user Ability of an application to grow in size as user
demand increases by adding additional processors demand increases by adding additional processors and/or nodesand/or nodes
Scale Up and Scale OutScale Up and Scale Out ManageabilityManageability
Cluster AdministratorCluster Administrator Single Point of Control (can be remote)Single Point of Control (can be remote) Cluster appears as a single-system imageCluster appears as a single-system image
Client PCsClient PCs
Server AServer A Server BServer B
Common Disk ArrayCommon Disk Array
HeartbeatHeartbeat
Virtual Server
Server ClusterServer ClusterLogical ViewLogical View
NLB HostNLB HostNLB HostNLB Host
NLB Virtual NLB Virtual IP AddressIP Address
NLB HostNLB Host NLB HostNLB Host NLB HostNLB Host
Internet/Internet/intranetintranetInternet/Internet/intranetintranet
Network Load Balancing ClusterNetwork Load Balancing ClusterLogical ViewLogical View
No single point of No single point of failurefailure
No performance No performance bottleneckbottleneck
No additional No additional hardware neededhardware needed
Grow incrementally as Grow incrementally as demand increasesdemand increases
Up to 32 nodes in a Up to 32 nodes in a clustercluster
Server Cluster TerminologyServer Cluster Terminology NodeNode
Individual computers that comprise a clusterIndividual computers that comprise a cluster 2 in Windows AS, 4 in Windows DCS2 in Windows AS, 4 in Windows DCS
HeartbeatHeartbeat Private Network between nodes in the cluster to check Private Network between nodes in the cluster to check
if node is aliveif node is alive External NetworkingExternal Networking
At least one public network so that outside world can At least one public network so that outside world can connect to the clusterconnect to the cluster
ResourceResource Managed Hardware or Software components (Disks, IP Managed Hardware or Software components (Disks, IP
addresses, applications, databases)addresses, applications, databases) Resource GroupResource Group
Resource Group is the collection of logically related Resource Group is the collection of logically related cluster resources that are treated as a unit during cluster resources that are treated as a unit during node operationsnode operations
Server Cluster Terminology 2Server Cluster Terminology 2 Common “Shared Nothing” Disk ArrayCommon “Shared Nothing” Disk Array
Collection of physical disks (SCSI RAID or Fibre Collection of physical disks (SCSI RAID or Fibre Channel) that will be accessed by the clusterChannel) that will be accessed by the cluster
Only one node can own a given resource at any given Only one node can own a given resource at any given timetime
Virtual Server (Key Concept!!!!)Virtual Server (Key Concept!!!!) The outside world sees the Virtual Server (server name The outside world sees the Virtual Server (server name
and IP address) as a single image system of the and IP address) as a single image system of the multiple nodes multiple nodes
Quorum Resource/DriveQuorum Resource/Drive Special and Required Common Resource - physical disk Special and Required Common Resource - physical disk
in the common cluster disk array that plays a critical in the common cluster disk array that plays a critical role in cluster operations (form/join)role in cluster operations (form/join)
Failover/FailbackFailover/Failback Act of moving from failed node(s) to surviving node(s) Act of moving from failed node(s) to surviving node(s)
and back again (if needed)and back again (if needed)
SQLServer 2000 SQLServer 2000 Failover ClusteringFailover Clustering
Feature of SQL Server 2000 Enterprise Feature of SQL Server 2000 Enterprise EditionEdition
Automatic Failover and “Quick Restart”Automatic Failover and “Quick Restart” Not a scalability solutionNot a scalability solution Doesn’t obviate need for Database Doesn’t obviate need for Database
Disaster/Backup/RecoveryDisaster/Backup/Recovery Requires specialized hardware solutionsRequires specialized hardware solutions Clients will be disconnected on failure but Clients will be disconnected on failure but
can reconnect relatively quicklycan reconnect relatively quickly Still connect to the same server/IP AddressStill connect to the same server/IP Address
Server/transaction recovery is automaticServer/transaction recovery is automatic Because the data and transaction log files are Because the data and transaction log files are
failed overfailed over Recovery from a failure looks like a normal server Recovery from a failure looks like a normal server
startup to the failed over serverstartup to the failed over server
Other SQLServer 2000 HA OptionsOther SQLServer 2000 HA Options Log ShippingLog Shipping
New feature of SQL Server 2000 Enterprise EditionNew feature of SQL Server 2000 Enterprise Edition Concept has been in use for a long timeConcept has been in use for a long time
Transaction logs from a primary database and Transaction logs from a primary database and apply them to a secondaryapply them to a secondary
Great primary or secondary method even if you Great primary or secondary method even if you can’t afford failover clusteringcan’t afford failover clustering
ReplicationReplication Not the traditional method of HA – technology has Not the traditional method of HA – technology has
been around for a long timebeen around for a long time Sometimes better than log shipping for Sometimes better than log shipping for
transactional consistencytransactional consistency Easy to replicate read-only dataEasy to replicate read-only data Possibly more complex, additional resourcesPossibly more complex, additional resources Uses – reporting, read only, possibly updates; Uses – reporting, read only, possibly updates;
partition datapartition data
Failover ConfigurationsFailover Configurations
Active-PassiveActive-Passive SQL Server on “primary” instance running, SQL Server on “primary” instance running,
secondary instance is idle until a failoversecondary instance is idle until a failover Active-ActiveActive-Active
SQL Server is running on both servers in the cluster SQL Server is running on both servers in the cluster simultaneously with different databasessimultaneously with different databases
But they are independent of each other (no load But they are independent of each other (no load balancing or data sharing)balancing or data sharing)
Active/Active/Active/Active on 4-node !Active/Active/Active/Active on 4-node ! NOTESNOTES
In SQL 2000, these terms are “deprecated”, still In SQL 2000, these terms are “deprecated”, still popular though…popular though…
In SQL 2000, we use the term “SQL Virtual Server In SQL 2000, we use the term “SQL Virtual Server Instances”Instances”
Failover Cluster in ActionFailover Cluster in Action
Server AServer A Server BServer B
Disk cabinet ADisk cabinet A
Disk cabinet BDisk cabinet B
HeartbeatHeartbeat
Cluster managementCluster management SQL ServerSQL ServerSQL ServerSQL Server
Bang !Bang !
Server AServer A Server BServer B
Disk cabinet ADisk cabinet A
Disk cabinet BDisk cabinet B
HeartbeatHeartbeat
Cluster managementCluster management SQL ServerSQL ServerSQL ServerSQL Server
All’s Clear !All’s Clear !
Server AServer A Server BServer B
Disk cabinet ADisk cabinet A
Disk cabinet BDisk cabinet B
HeartbeatHeartbeat
Cluster managementCluster management SQL ServerSQL Server
SQL ServerSQL Server?
Failback (if needed)Failback (if needed)
Server AServer A Server BServer B
Disk cabinet ADisk cabinet A
Disk cabinet BDisk cabinet B
HeartbeatHeartbeat
Cluster managementCluster management SQL ServerSQL ServerSQL ServerSQL Server
Resource1Resource1
Resource2Resource2
11
Rolling UpgradesRolling Upgrades
UpgradeUpgradeResource2Resource2Resource1Resource1
Resource2Resource2
11 Resource1Resource122
Rolling UpgradesRolling Upgrades
UpgradeUpgradeResource2Resource2Resource1Resource1
Resource2Resource2
11
Resource1Resource1
Resource2Resource2
33
Resource1Resource122
UpgradeUpgrade
Rolling UpgradesRolling Upgrades
UpgradeUpgradeResource2Resource2Resource1Resource1
Resource2Resource2
11
Resource1Resource1
Resource2Resource2
33
Resource1Resource122
Resource1Resource1
Resource2Resource2
44UpgradeUpgrade
Rolling UpgradesRolling Upgrades
Best Practices and ResourcesBest Practices and Resources
Implementation TipsImplementation Tips
Plan, plan, plan!Plan, plan, plan! Plan shared disk spacePlan shared disk space Don’t skimp on hardwareDon’t skimp on hardware Test, test, test!Test, test, test! Cluster failoverCluster failover Hardware failuresHardware failures
Network cards and cablesNetwork cards and cables Shared disk arrays and cablesShared disk arrays and cables Entire node shutdownsEntire node shutdowns
SQL Server and application failuresSQL Server and application failures
Best Practices and ResourcesBest Practices and Resources Be prepared to READ a lotBe prepared to READ a lot
SQL2K BOLSQL2K BOL Great place to start for common questions, Great place to start for common questions,
installation order, deployment considerations, installation order, deployment considerations, supported configurations, etc.supported configurations, etc.
SQL2K Resource KitSQL2K Resource Kit Must Read Part 4 Chapters 12-16Must Read Part 4 Chapters 12-16
Presentation Resources PagePresentation Resources Page Microsoft supports only validated cluster Microsoft supports only validated cluster
configurations (Hardware Compatibility List)configurations (Hardware Compatibility List) Special ConsiderationsSpecial Considerations
Ensure that each server is a member of the same Ensure that each server is a member of the same domaindomain
Only one MSDTC per ClusterOnly one MSDTC per Cluster SQL 2000 Analysis service (OLAP)SQL 2000 Analysis service (OLAP) SQL Mail (MAPI is not cluster aware)SQL Mail (MAPI is not cluster aware) Nothing should go on the Quorum DriveNothing should go on the Quorum Drive
More ResourcesMore Resources
Web ResourcesWeb Resources Windows 2000 Clustering Technologies Home Page (Technical and Introductory Windows 2000 Clustering Technologies Home Page (Technical and Introductory
Overviews)Overviews)http://www.microsoft.com/windows2000/technologies/clustering/default.asphttp://www.microsoft.com/windows2000/technologies/clustering/default.asp
Step-by-Step Guide to Installing Cluster ServiceStep-by-Step Guide to Installing Cluster Servicehttp://www.microsoft.com/windows2000/techinfo/planning/server/clustersteps.asphttp://www.microsoft.com/windows2000/techinfo/planning/server/clustersteps.asp
Building a Highly Available Database ClusterBuilding a Highly Available Database Clusterhttp://msdn.microsoft.com/library/techart/d5clustering.htmhttp://msdn.microsoft.com/library/techart/d5clustering.htm
Best Practices for End-to-End High AvailabilityBest Practices for End-to-End High Availabilityhttp://www.microsoft.com/technet/avail/bestprac/bestprac.htmhttp://www.microsoft.com/technet/avail/bestprac/bestprac.htm
Microsoft Support ArticlesMicrosoft Support Articles
Q243218, INF: Installation Order for SQL Server 2000 Enterprise Edition on Microsoft Q243218, INF: Installation Order for SQL Server 2000 Enterprise Edition on Microsoft Cluster ServerCluster Serverhttp://support.microsoft.com/support/kb/articles/Q243/2/18.ASPhttp://support.microsoft.com/support/kb/articles/Q243/2/18.ASP
Q260758, INF: Frequently Asked Questions - SQL Server 2000 - Failover ClusteringQ260758, INF: Frequently Asked Questions - SQL Server 2000 - Failover Clusteringhttp://support.microsoft.com/support/kb/articles/q260/7/58.asphttp://support.microsoft.com/support/kb/articles/q260/7/58.asp
Q274446, INF: Upgrade to a SQL Server 2000 Failover Solution Recommended for All non-Q274446, INF: Upgrade to a SQL Server 2000 Failover Solution Recommended for All non-SQL Server 2000 Virtual ServersSQL Server 2000 Virtual Servershttp://support.microsoft.com/support/kb/articles/Q274/4/46.ASPhttp://support.microsoft.com/support/kb/articles/Q274/4/46.ASP
Microsoft NewsgroupsMicrosoft Newsgroupsmicrosoft.public.sqlserver.clusteringmicrosoft.public.sqlserver.clustering
Other ResourcesOther Resources Microsoft Support WebcastsMicrosoft Support Webcasts Windows Clustering: An Overview of Microsoft Clustering Technologies Windows Clustering: An Overview of Microsoft Clustering Technologies
http://support.microsoft.com/servicedesks/Webcasts/WC012100/WCBLURB012100.ASPhttp://support.microsoft.com/servicedesks/Webcasts/WC012100/WCBLURB012100.ASP Introduction to Microsoft SQL Server 2000 Clustering Introduction to Microsoft SQL Server 2000 Clustering
http://support.microsoft.com/servicedesks/webcasts/wc051001/wcblurb051001.asphttp://support.microsoft.com/servicedesks/webcasts/wc051001/wcblurb051001.asp