Recently I was working with one of the customer who was migrating his SAP environment from IBM AIX to Cisco’s UCS platform and the customer was looking for some Best Practices from a VMware standpoint. I thought, this would make a good blog post.
There’s lot of information out there, but the following should help you get started.
So here they are:
- The basis team should leverage Early Watch Reports to come up with sizing for the SAP virtual machines. Use requirements from the basis team for the application and DB servers for all the modules. The sizing should be done based on their existing environment and its utilization.
- Follow SAPS based workload Sizing recommendations.
- Reserved all memory based on SAP best practices for production. Definitely no overcommitment of Memory.
- Size VMs so that CPU and memory will fit within NUMA boundaries.
- Reserve Memory for SAP Production Virtual Machines.
- Ensure database servers separate LUNS for data , logs, and archive.
- The Guest OS swap will be separated to a LUN that is not replicated.
- The boot disk and all other disk partitions should be aligned for optimal performance at the VMFS and the OS level.
- Leverage Cisco UCS service profile to create consistent server Hardware configurations.
- Plan vCPU per CPU core based on applications requirements. HT should be enabled to reduce impact of over commitment.
- The ESX hosts for the SAP environment needs to exist in a dedicated cluster with its own networking and storage zoning.
- Ensure virtual machines are configured to fit within NUMA nodes.
- Host profiles should be leveraged to ensure consistent configuration across all ESX hosts in the cluster.
- Database Storage Design should be similar to Physical. We also need to factor in space to be used by the .vswp files in the Virtual Machines. The size of a .vswp file is equal to Total configured memory – reservation if provided. So if no reservations are provided, then the size of each .vswp file is equal to the amount of memory and hence the Storage sizing needs to factor that as well for the overall sizing.
- Use separate LUNs for OS,Data and Swap.
- Dedicate LUNs provided for DB related files to guarantee the required performance.
- All Database and Application disks should be Eager-Zero Thick Provisioned.
- Guest Page Files should be stored in a separate disks.
- At the Storage level, use Thick Provisioning.
- Use the UCS capability to create vNICs for separate ports for management,vMotion and Production traffic. Separate them by VLANs.
- The standard SAP Rules apply for Databases. See SAP Note 592393.
- See SAP Note 1056052 for additional vSphere Guidelines – https://service.sap.com/sap/support/notes/1056052
Few good online resources:
Also note there was a recent announcement at SAPHIRE 2016, few days back(17th May) that SAP supports SAP HANA on vSphere 6 . Please see http://blogs.vmware.com/apps/2016/05/sap-hana-on-vsphere-deployment-options-and-best-practices.html