Reboot SAP HANA on node 1 - SAP HANA on AWS

Reboot SAP HANA on node 1

Description: Simulate a crash of the primary site node running the primary SAP HANA database.

Run node: Primary SAP HANA database node

Run steps:

  • Crash the primary database system using the following command as root:

    prihana:~ # crm status Stack: corosync Current DC: prihana (version 1.1.18+20180430.b12c320f5-3.24.1-b12c320f5) - partition with quorum Last updated: Thu Nov 12 12:09:44 2020 Last change: Thu Nov 12 12:09:11 2020 by root via crm_attribute on prihana 2 nodes configured 6 resources configured Online: [ prihana sechana ] Full list of resources: res_AWS_STONITH (stonith:external/ec2): Started prihana res_AWS_IP (ocf::suse:aws-vpc-move-ip): Started prihana Clone Set: cln_SAPHanaTopology_HDB_HDB00 [rsc_SAPHanaTopology_HDB_HDB00] Started: [ prihana sechana ] Master/Slave Set: msl_SAPHana_HDB_HDB00 [rsc_SAPHana_HDB_HDB00] Masters: [ prihana ] Slaves: [ sechana ] prihana:~ # echo 'b' > /proc/sysrq-trigger
Note

To simulate a system crash, you must first ensure that /proc/sys/kernel/sysrq is set to 1.

Expected result:

  • The cluster detects failed node (node 1), declares it “UNCLEAN” and sets the secondary node (node 2) to status “partition WITHOUT quorum”.

  • The cluster fences node 1 and promotes the secondary SAP HANA database (on node 2) to take over as primary.

    sechana:~ # crm status Stack: corosync Current DC: prihana (version 1.1.18+20180430.b12c320f5-3.24.1-b12c320f5) - partition with quorum Last updated: Thu Nov 12 12:15:51 2020 Last change: Thu Nov 12 12:15:31 2020 by root via crm_attribute on sechana 2 nodes configured 6 resources configured Online: [ sechana ] OFFLINE: [ prihana ] Full list of resources: res_AWS_STONITH (stonith:external/ec2): Started sechana res_AWS_IP (ocf::suse:aws-vpc-move-ip): Started sechana Clone Set: cln_SAPHanaTopology_HDB_HDB00 [rsc_SAPHanaTopology_HDB_HDB00] Started: [ sechana ] Stopped: [ prihana ] Master/Slave Set: msl_SAPHana_HDB_HDB00 [rsc_SAPHana_HDB_HDB00] Masters: [ sechana ] Stopped: [ prihana ]
  • The overlay IP address is migrated to the new primary (on node 2).

  • With the AUTOMATIC_REGISTER parameter set to "true", the cluster restarts the failed SAP HANA database and automatically registers it against the new primary.

Recovery procedure:

  • Start node 1 (EC2 instance) with the AWS Management Console or AWS CLI tools and start Pacemaker (if it’s not enabled by default).