Issue link: https://epubs.iltanet.org/i/4636
www.iltanet.org Infrastructure Technologies 11 revisiting disaster recovery in a virtualized environment SAN UPGRADE Staying with NetApp technology, we purchased the following: • FAS3140A with 15K RPM Fibre Channel drives with both Fibre Channel and iSCSI protocols for the primary data center. Primary servers are connected using Fibre Channel and secondary servers via iSCSI to minimize costs • FAS2020 with SATA disks with iSCSI connectivity at the DR site • NetApp SnapMirror SAN-to-SAN replication • NetApp FAS deduplication technology (included with the SAN) • Common Internet file system (CIFS) storage, which allows the SAN to act like a Windows file server in order to eliminate any Windows based file server VMs, including the Autonomy iManage document store The migration process was quite straightforward. At the primary site, the new SAN was connected to the existing Fibre Channel infrastructure, and initial testing and burn-in were performed. Once the new volumes were presented to the ESX hosts, it was a simple matter of using VMware Storage VMotion to move the guests with zero downtime. Before retiring the old SAN, a data scrub was performed. The SAN for the DR site was delivered to the primary site so that a high-speed connection could be used to perform the initial NetApp SnapMirror data synchronization before being shipped to the DR site. Ongoing data replication is performed over the MPLS network, which is throttled via the Cisco infrastructure to ensure user-facing data has priority. The firm elected to use the Cisco infrastructure over NetApp's built-in throttling, because the Cisco routers have a broader picture of the network traffic, offering granularity in prioritizing and throttling network traffic. DEDUPLICATION At the time of the initial centralization and virtualization, the total firm data storage was 1.3TB. The explosive growth of data over three years necessitated a purchase of 8TB of usable storage on the new primary SAN. Integrated with the SAN is data deduplication technology, which will optimize space by identifying identical blocks of data at the volume level and combining them to a single instance. Utilizing deduplication, which is largely dependent on the type of data, the resulting space savings were: • VMware system volumes: 60-65 percent • VMware data volumes: 35-40 percent • CIFS storage: 20 percent REPLICATION Replication of data to the DR SAN is accomplished with SAN-based SnapMirror technology, which creates a read-only copy at the DR site. After the initial replication, only the changes are sent. To significantly lessen the amount of traffic, deduplication is scheduled to