We are implementing SAP ERP & BPC on HANA. For high availability @ Production, we have procured 2 HANA boxes. We have not opted Scale out HA but SAP System Replication. Replication is tested and working fine.
We have faced a challenge in getting configured the virtual IP which will reference both HANA boxes. The idea is not to manually change the IP of the Secondary Box to change it into Primary.
How can this be done on Suse Linux for SAP HANA.
sorry if this sounds a bit plain… you’ll need some trigger event and then add a script to take the appropriate measures?
I’m not into SAP, my assumption from your description is that SAP runs dual-active. I don’t know if moving the IP around is supported, but if it is, you could work your way along the following lines:
if you know the manual way to do this, note down the commands and add them to a script (it might be more than activating the IP, like restarting services so they take note of the changed configuration)
the same goes for deactivation
find the appropriate trigger event (perhaps some SAP log message indicating it took over? I’d prefer that over running things like connectivity checks yourself: You’ll only activate the IP if SAP actually believes to be in charge.)
don’t forget to implement a way to de-activate the IP on the other node, in case some non-fatal issue caused the take-over… running two nodes with the same IP will give some interesting issues
I’d generally change the systems so that activation/deactivation of the IP is done by your scripts alone, not via system configuration. That way you can take measures to avoid activating the IP during reboot of the failing node…
If the required mechanisms are more complex, then you might think about using Pacemaker (from SLE HAE extension) - but this might be “too much” for your specific case.