Red Hat Enterprise Linux HA Solution for SAP HANA Scale Out and System Replication

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As SAP HANA takes on a central function as the primary database platform for SAP landscapes, requirements for stability and reliability increase dramatically. Red Hat Enterprise Linux (RHEL) for SAP Solutions meets those requirements by enhancing native SAP HANA replication and failover technology to automate the takeover process. During a failover in a scale-out SAP HANA system replication deployment, a system administrator must manually instruct the application to perform a takeover to the secondary environment in case there is an issue in the primary environment.

This solution is for experienced Linux Administrators and SAP Certified Technology Associates. The solution contains planning and deployment information for SAP HANA scale out with system replication, as well as information on Pacemaker integration with RHEL 7.

For more information, see Red Hat Enterprise Linux HA Solution for SAP HANA Scale Out and System Replication.

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2 Comments

Some feedback for this documentation:

  • it would be nice to have link for this from article Where I can find documentation for SAP products on RHEL and other Red Hat products?
  • is there HTML version of the attached PDF?
  • I consider it a quite bad practice to recommend at this time to create pacemaker resources as primitives to just convert them in next step to Clone or Master/Slave. Why? Because people forget and because it can be done in single command that either succeeds or fails.
  • Would it be possible (and maybe better) to use quorum network device instead of 'majoritymaker' node that in the end is not running any resources? (using quorum network device would remove need for constraints that avoids that node for HANA resources as quorum device just adds vote and doesn't run any cluster resources)
  • page64 (top) cdtrace is most probably missing space and should be cd trace, right?
  • in general it is a bit hard to follow in the PDF on what is 'command' and what is 'command output' - I would suggest using something like root@dc1hana01# cd trace for example so it is clear 1. which user, 2. which system, 3. what command should be used. Now both commands and output are just a mix. - In fact this was used in some places where I can see things like rh1adm@dc2hana01:/usr/sap/RH1/HDB10>. But consistency through document would be better than just "some places".
  • on consistency note: it looks like the commands are mostly in blue color but not always (page62,page64 as examples). It is confusing on what is what (command vs output)
  • mentioning all 'op xxx' options for resource agents is quite daunting to rewrite while the pcs itself will use the defaults unless other are specified. removing them from examples would make commands shorter and easier to read. Instead of pcs resource create rsc_SAPHana_RH1_HDB10 SAPHanaController \ SID=RH1 \ InstanceNumber=10 \ PREFER_SITE_TAKEOVER=true \ DUPLICATE_PRIMARY_TIMEOUT=7200 \ AUTOMATED_REGISTER=true \ op start interval=0 timeout=3600 \ op stop interval=0 timeout=3600 \ op promote interval=0 timeout=3600 \ op monitor interval=60 role="Master" timeout=700 \ op monitor interval=61 role="Slave" timeout=700 you can then get to something like pcs resource create rsc_SAPHana_RH1_HDB10 SAPHanaController \ SID=RH1 \ InstanceNumber=10 \ PREFER_SITE_TAKEOVER=true \ DUPLICATE_PRIMARY_TIMEOUT=7200 \ AUTOMATED_REGISTER=true

In overall Thank you for the documentation and please consider the above as feedback for improvement to make it even better.

Hi Ondrej,

Thank you for your feedback; it is very much appreciated! I'm working with the SMEs on a response for each item. We'll add it to this thread as soon as it is ready.

Kind regards, Sharon.