Most organizations are not too keen on starting virtualization of servers directly with their mission critical applications. However, CMI FPE Limited is an exception, as it not only put SAP on the virtual server platform, but also carried out its entire ERP migration on VMware’s vSphere 4.0.
Integrating virtualization and SAP
In mid-2009, CMI FPE Limited recognized the need to replace its small cluster of ageing servers running SAP ECC5. “Our vision was fourfold, and virtualization of servers was one aspect of it,” says Vijay Karayi, the director for management assurance, quality management systems and CIO at CMI FPE Limited. These four objectives comprised migrating from 32-bit to 64-bit architecture, having a centralized storage instead of local storage, virtualization of servers, and having offline backups through the tape library.
For undertaking virtualization of servers, CMI FPE Limited decided to opt for VMware since it was the leading vendor in this space. Karayi states, “We did not want to experiment, and after a lot of research, decided to go with VMware vSphere 4.0 version.” The vSphere 4.0 project’s planning took considerable time as the company was trying to do several things at the same time like upgrading from SAP ECC5 to ECC6 and from Microsoft SQL 2000 to SQL 2008.
The complexity in this vSphere 4.0 deployment was that the entire environment was taken on virtual platform and ECC5 was upgraded to ECC6 on it. It was basically a technical upgrade, and not functional in nature. As Karayi mentions, “We had to do raw disk mapping for the SAP part as it is very I/O intensive. We also had to do thick provisioning rather than thin provisioning for the storage.”
Virtualization of servers on vSphere 4.0 for mission critical applications like SAP, however, warrants a few precautions. Karayi explains, “We went up from I/O of 700 to 2200 and used SAP Quick Sizer to clear sizing of disk arrays keeping in mind the tradeoff between the disk size and I/O.” CMI FPE Limited also did post support check from SAP and based on recommendation, had a nested redundant array of independent disks (RAID) for the storage.
All equipment was supplied by Dell. Post the virtualization of servers on vSphere 4.0, the data and virtual memory system (VMS) reside on an upgraded EMC CX4-120 SAN. Currently, there are 19 servers running on five Dell R710 running Windows platform, residing in CMI FPE Limited’s Mumbai data center. Offline backups of virtual machines running on vSphere 4.0 are also being done. The downtime for the SAP ECC5 upgrade, including virtualization of servers was about 65 hours, and the implementation went live in January 2010.
According to Karayi, virtualization of servers using vSphere 4.0 has resulted in increased SAP productivity. Karayi observes, “Inventory reports like NB52 that used to take around five minutes can now be done in one-third of the time.” Also, the server rack space size has decreased from two to one as part of vSphere 4.0 migration.
The earlier deployment had two physical servers in cluster mode, but now there is no need for clustering because of nested RAID for the database and the high availability feature in vSphere 4.0. Future plan around virtualization of servers at CMI FPE Limited involves putting another mission critical application AutoCAD on vSphere 4.0.