The quarterly publication of the International Legal Technology Association
Issue link: https://epubs.iltanet.org/i/230349
case studies The Removal of Complexity: ARTICLE GEEK FACTOR Data Center Workload Mobility and Disaster Recovery at KWM by Paul O'Leary, Liza Dennis and Ben Swindale of King & Wood Mallesons "Fools ignore complexity. Pragmatists suffer it. Some can avoid it. Geniuses remove it." — Alan Perlis In the IT departments of the world, complexity is assumed. In fact, if complexity is absent, the general consensus is there must be something wrong with the solution. "It's not robust," "it won't handle my specific case" and "there don't seem to be enough options" would be common complaints about any technology that removes all extraneous features or abilities and focuses on a core competency. A team at King & Wood Mallesons (KWM), representing engineering to management, have done just that — removed extraneous features in our disaster recovery (DR) system to reduce administrative complexity. Simple, Yet Reliable We deployed a DR and workload mobility solution and use it operationally. It was implemented intentionally to present administrators with just two questions: • Do you want system X powered on at the recovery site? • In what order would you like the systems to come up? KWM invested the time and effort to implement Overlay Transport Virtualization (OTV) from Cisco using Nexus 7000 data center switches, VMware Site Recovery Manager (SRM) and EMC RecoverPoint to make a complex task as straightforward as asking those two questions of our administrators. By owning the difficult 34 Peer to Peer design and deployment tasks that will apply to every workload we run, we can present simple choices to the business and be consistent in every recovery or "teleporting" of workloads from site to site. Using OTV, we engineered our subnets to be available across multiple sites. That means IP connectivity is available without changing the address space of the operating system, even when moving the whole virtual machine (VM) from one physical location to another. Using Border Gateway Protocol (BGP), we're able to make the OTV Virtual Local Area Networks (VLANs) available via redundant Multiprotocol Label Switching (MPLS) connections for remote sites accessing resources in the data center. The OTV design took some work to ensure we got it right. When designing a Layer 2 overlay on top of a Layer 3 network, we were concerned about introducing loops, latency or connectivity issues, but it has worked well. It's the cornerstone of being able to recover a system without requiring administrative intervention. RecoverPoint manages the input/output from logical unit numbers (LUNs) located on specific Storage Area Networks (SANs). These are logged and replicated without performance penalty to the VM. They are then tracked and managed at the remote site waiting for the request to mount the LUN. It is then a complete block-forblock replica of the original. The journaling aspect of RecoverPoint allows the system to handle any link loss, or bandwidth reductions