Reboot SAP HANA on node 2 - SAP HANA on Amazon
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Reboot SAP HANA on node 2

Description — Simulate a crash of the primary node (on node 2) running the primary SAP HANA database.

Run node — Primary SAP HANA database node (on node 2)

Run steps:

  • Crash the node running primary SAP HANA (on node 2) using the following command as root:

    shutdown
    [root@sechana ~]# pcs status Cluster name: rhelhanaha Stack: corosync Current DC: sechana (version 1.1.19-8.el7_6.5-c3c624ea3d) - partition with quorum Last updated: Tue Nov 10 17:54:13 2020 Last change: Tue Nov 10 17:53:48 2020 by root via crm_attribute on prihana 2 nodes configured 6 resources configured Online: [ prihana sechana ] Full list of resources: clusterfence (stonith:fence_aws): Started prihana Clone Set: SAPHanaTopology_HDB_00-clone [SAPHanaTopology_HDB_00] Started: [ prihana sechana ] Master/Slave Set: SAPHana_HDB_00-master [SAPHana_HDB_00] Masters: [ sechana ] Slaves: [ prihana ] hana-oip (ocf::heartbeat:aws-vpc-move-ip): Started sechana Daemon Status: corosync: active/enabled pacemaker: active/enabled pcsd: active/enabled [root@sechana ~]# 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 the failed node (node 2), declares it “UNCLEAN”, and sets the secondary node (node 1) to status “partition WITHOUT quorum”.

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

    [root@prihana ~]# pcs status Cluster name: rhelhanaha Stack: corosync Current DC: prihana (version 1.1.19-8.el7_6.5-c3c624ea3d) - partition with quorum Last updated: Tue Nov 10 18:22:00 2020 Last change: Tue Nov 10 18:21:49 2020 by root via crm_attribute on prihana 2 nodes configured 6 resources configured Online: [ prihana ] OFFLINE: [ sechana ] Full list of resources: clusterfence (stonith:fence_aws): Started prihana Clone Set: SAPHanaTopology_HDB_00-clone [SAPHanaTopology_HDB_00] Started: [ prihana ] Stopped: [ sechana ] Master/Slave Set: SAPHana_HDB_00-master [SAPHana_HDB_00] Masters: [ prihana ] Stopped: [ sechana ] hana-oip (ocf::heartbeat:aws-vpc-move-ip): Started prihana Daemon Status: corosync: active/enabled pacemaker: active/enabled pcsd: active/enabled [root@prihana ~]#
  • The overlay IP address is migrated to the new primary (on node 2).

  • Because AUTOMATED_REGISTER is set to true, the cluster restarts the failed SAP HANA database and registers it against the new primary when the EC2 instance is back up.

Recovery procedure:

  • Start node 2 (EC2 instance) using Amazon Web Services Management Console or Amazon CLI tools.