Transcription
SAP High Availability inAzure Using SUSE Linux[BP-1404]1
AgendaBasic SAP ArchitectureSAP HA Architecture in AzurePacemakerAzure Load BalancerDemo of unplanned failover2
SAP Architecture3
Basic SAP seServerShared DiskDatabaseStorage4
S/4HANA High Availability Architecture in Azure5
Availability Set (99.95%)Availability Zones (99.99%)6
SUSE HighAvailabilityExtension7
The Goal of HAMTTR9
SUSE High Availability OverviewvIPvIPSAPSAPSAPFencing (stonith)Resource Agents (RAs)pacemaker (crm)corosync (cluster membership)KernelStorage(SBD)Kernel10
Resource AgentsProvides ‘intelligence to Pacemaker’A script used to start/stop/monitor a resource Ideally should be Open Cluster Framework compliant Well defined return values Mandatory operations Return value passed back to Pacemaker Many providers of RAs Ships with around 140 RA out of the box. Resource Agents for SAP HANA included in SLES for SAP Applications14
SAP HANA Resource Agents15
Why Do We Need Fencing?To a cluster node, loss of a peer node is indistinguishable from loss ofcommunication with that node.In the former case, is it safe to failover resources?And in the latter case?16
Split Brain When a cluster partitions due to network failure Neither side knows if the other is still alive Worst case scenario: each side attempts to failover the other's resource Better scenario: neither side does anything(But then, why do we have a cluster?) Best scenario: one side is able to guarantee that the other is down Fencing is about moving from an UNKNOWN state to a KNOWN state17
SUSE HighAvailability withSAP CentralServices18
Enqueue-Replication VersionsENSA1ENSA219
Central Services – Multi SID20
Architecture options for SAP on AzureFilesystem BYO SUSEcluster ANF NFS (future)AzavailabilityoptionsFencingagent Av Set Av Zone SBD Azure Fencingagent (future)21
Floating IP: Two Basic Architectures PossiblePASPASAzure LoadBalancerFloating IPHana1Hana2Hana1Hana222
Let’s look at the first case “Floating” IP can be moved fromone machine to another viaAPI/CLI IP Move takes approximately 2minutesPASHanaSystemReplicationFloating IPSr takeoverHana1Hana223
Load BalancerClientAzure LoadBalancerHana1Hana2Backend Pool24
PASAzure ationFloating IPSr takeoverHana1Hana225
SOCAT & Virtual IP Network Resourcesudo crm configure primitive rsc ip HN1 HDB03 ocf:heartbeat:IPaddr2 \ meta target-role "Started" is-managed "true" \ operations \ id "rsc ip HN1 HDB03-operations" \op monitor interval "10s" timeout "20s" \ params ip "10.0.0.13"sudo crm configure primitive rsc nc HN1 HDB03 anything \ paramsbinfile "/usr/bin/socat" cmdline options "-U TCPLISTEN:62503,backlog 10,fork,reuseaddr /dev/null" \ op monitor timeout 20sinterval 10 depth 0sudo crm configure group g ip HN1 HDB03 rsc ip HN1 HDB03 rsc nc HN1 HDB0326
Unplanned FailoverSeveral mechanisms for testing: Shut down machine from Azureportal ps aux grep sbd, kill inquisitor service pacemaker stop28
TakeawaysRead the DocumentationSetup & test your configuration andkeep testingUnderstand the operationsMonitoring & Alerts29
ResourcesLinks to l/Links to deployments[TUT-1226]SAP HA on SUSE: All you need to know[TUT-1396]"Day 2" Operations of SAP HANA Cluster using SUSE HighAvailability on Public Cloud[HOL-1064]SAP HANA scale-out with high availability NFS usingDRBDTraining & p/[BP-1351]SUSE High Availability for SAP HANA: Tales from the realworld, tips, tricks, & troubleshootingAzure training & certifications[HOL-1225]High Availability for SAP application servers using ENSA2enqueue replication.30
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Load Balancer Hana 1 Hana 2 Client Azure Load Balancer. 25 Hana 1 Hana 2 PAS Floating IP Hana System Replication Sr_takeover Azure Load Balancer Health Probe Health . SAP HANA scale-out with high availability NFS using DRBD [BP-1351] SUSE High Availa
