Manual System Failover for ActiveDR

ActiveCluster
Audience
Public
Product
FlashArray
FlashArray > Purity//FA
Source Type
Documentation

The SAP HANA environment is configured as follows:

  • 2 separate distinct SAP HANA Systems.
    • Compute 1 and Compute 2
    • Each has a separate volume mounted to /hana/shared from the localized array. i.e /hana/shared for compute 1 comes from array 1.
    • A different SID can be set on either system. If a name change is required then this can be done by following this guide.
    • The exact same version of SAP HANA is installed on both systems.
  • 2 separate distinct FlashArray storage platforms.
    • Array 1 and Array 2
    • The arrays can be of a different model - but the number of supported nodes is established by the lower FlashArray model.
    • The ActiveDR replica link has been created and the baseline established between the arrays.

For both Scale Up and Scale Out the initial configuration is the same as the configuration for ActiveCluster with the following exceptions :

  • A different SID can be used on the source and target systems.
  • There are no preffered paths and the world wide names of the volumes will be different on Array 1 and Array 2. For Scale Out Scenarios the Storage section of the global.ini file will need to be updated with the correct volume names.
  • To bring the SAP HANA instance up on the target array for failover or migration the following steps must be followed :

1. Stop the Source SAP HANA System 


/usr/sap/hostctrl/exe/sapcontrol -nr <instance number> -function Stop

Wait until the instances have stopped on each system by using the following command:


/usr/sap/hostctrl/exe/sapcontrol -nr <instance number> -function GetProcessList

2. Unmount the log and data volumes

For a Scale Out environment each node should be checked to ensure no volumes are mounted.


umount <path to volume>

3. Demote the Source array POD

Note:

Do not demote the POD until all volumes in the POD have been unmounted from the operating system

On the source array execute the following :


purepod demote --quiesce <POD NAME>

Wait until the POD is listed as "demoted" on the source array before continuing.

4. Promote the Target array POD

On the target array execute the following :


purepod promote <POD NAME>

5. Connect the log and data volumes to the target system(s) , mount them to the relevant SAP HANA volume locations (Scale Up) or SAP HANA Host Failover with ActiveCluster and ActiveDR and then start the instance.