Virtualization Implementing automated replication for cost-effective disaster recovery By Fabian Salamanca and Javier L. Jiménez Dell™ Advanced Infrastructure Manager (AIM) software and Dell Compellent™ storage together help create a reliable disaster recovery platform that supports multisite replication and optimizes business continuity cost-effectively. echnology forms a front line of defense The first step in creating a business continuity Dive deeper: Multisite replication when enterprises require continuous plan is to identify critical applications and functions availability for business-critical that must be protected. Next, organizations A successful business continuity applications and data. As a result, IT delineate the recovery time objective (RTO), plan helps ensure availability of T business-critical applications. efforts are intensifying to establish protection from which specifies the maximum allowable time to Download this Dell technical sudden disruption or downtime in mission-critical restore each critical process. Then, they define the white paper, and discover how Dell AIM and Dell Compellent applications such as e-mail, Internet presence, recovery point objective (RPO), which targets the storage provide an efficient enterprise resource planning (ERP), and customer maximum acceptable amount of data at risk of disaster recovery platform using relationship management (CRM). Although high- loss after an adverse event occurs. Time to data multisite replication. availability clustering provides local protection, critical (TTD) is the time required for retrieving backup dell.to/s9UZI0 applications also require geographical protection. data and delivering it to the recovery site. And the stakes for preserving business continuity are RTO and RPO are key measures that drive the high: among organizations that experience a major configuration of a disaster recovery implementation, loss of business data, a significant number face critical which also affects its cost. Figure 1 shows problems and only a few are able to overcome them. the relationship among RTO, RPO, and TTD. 72 2011 Issue 04 | dell.com/powersolutions Reprinted from Dell Power Solutions, 2011 Issue 4. Copyright © 2011 Dell Inc. All rights reserved. Virtualization Reduced RTO and RPO can translate Data Restore into an enhanced business continuity Snapshot Disaster restoration operation Snapshot response and a cost-effective disaster recovery implementation. Time One approach to creating a cost- RPO effective business continuity deployment leverages Dell Advanced Infrastructure Manager (AIM)—a component of the Dell TTD Virtual Integrated System (VIS) portfolio— together with Dell Compellent Storage Center™ RTO storage area network (SAN) arrays. This architecture is designed to provide reliable Figure 1. Mapping RTO, RPO, and TTD in a disaster recovery scenario data replication, OS image integrity, and fast workload migration. The example either a virtual or a physical server. Included center assets and allows IT organizations to configuration described in the section persistent identification settings help leverage existing investments for increased “Efficiently implementing disaster recovery” ensure the persona has access to the same return on investment (ROI). deploys Fibre Channel for OS image and resources no matter what changes may data access, IP and Ethernet networks for occur in a data center managed with AIM. Intelligently managing and replicating long-distance wide area network (WAN)– AIM network-booted personas can enterprise data based replication using Internet SCSI boot on any validated resource, and AIM Using Dell Compellent storage helps (iSCSI) connectivity, and AIM to manage helps ensure that whichever resource is administrators actively and intelligently the provisioning of workload identities and running the persona, that resource has manage enterprise data throughout its life network configuration. the required network and storage access. cycle, enabling organizations to constantly For example, at any given time a network- adapt to changing conditions. Together, Flexibly managing recovery and booted persona can be running on a the Dell Fluid Data architecture, storage workload mobility physical server, such as a Dell PowerEdge™ virtualization, intelligent software, and modular Dell AIM helps IT organizations build a R610 rack server, and after business hours it hardware enhance IT efficiency, simplicity, next-generation data center by providing can run on either a VMware® virtualization– and security for enterprise storage. Built-in rapid workload mobility and recovery based or a Microsoft® Hyper-V™–based intelligence and automation help ensure data management across physical and virtual virtual machine to help reduce power is available when and where it is needed, and machines in heterogeneous environments. consumption and cooling costs. This an open, persistent hardware platform scales IT administrators can deploy AIM to create dynamic capability enables the workload to in line with business needs to help protect a cost-effective IT infrastructure that use low-cost hardware or virtual machines long-term storage procurements. easily changes—physically and virtually—as when the load is expected to be low and Leveraging Remote Instant Replay for circumstances demand. It helps increase IT retarget to high-performance resources Dell Compellent array replication across asset utilization, can recover services quickly when the load is expected to be high. multiple sites helps reduce the cost and if problems occur, and enables services to be All data related to a network-booted complexity of replication while redefining scaled rapidly to support business needs. persona resides on a SAN, leveraging the backup and recovery. Because this approach AIM creates a dynamic and flexible integrated management functionality is designed to keep all locations active, IT cable-once data center infrastructure by associated with SANs. If a network-booted organizations can maximize utilization— coordinating end-to-end network, storage, persona resides within a Dell Compellent enabling even legacy and entry-level systems and computing resources. AIM captures virtual storage array, for example, it can to be leveraged as appropriate. workload images—personas—in central benefit from the Dell Fluid Data™ architecture, storage that include the OS, the optional AIM using Dell Compellent Data Instant Replay™ Efficiently implementing agent software, application software, and software for backup and recovery and Dell disaster recovery storage and networking settings—including Compellent Remote Instant Replay™ software Together, Dell AIM and Dell Compellent either iSCSI or Fibre Channel—and other for long-distance replication. AIM provides storage offer rich complementary features settings for running an application on an open approach that works with many data that form a cost-effective foundation for Reprinted from Dell Power Solutions, 2011 Issue 4. Copyright © 2011 Dell Inc. All rights reserved. dell.com/powersolutions | 2011 Issue 04 73 Virtualization business continuity planning. At the Dell a simulated disaster recovery scenario using the direct SAN access option in AIM. Customer Briefing Center in Mexico City, comprising two sites that support production Administrators can implement SAN zoning Mexico, and the Dell Solution Center in operation of workloads, replication, and using the World Wide Name (WWN) of the Round Rock, Texas, Dell engineers configured disaster recovery. The main site ran a host bus adapter (HBA) that is assigned to persona using the Red Hat® Enterprise the persona. Linux® 5 64-bit OS on a Dell PowerEdge At the remote site, the persona was #!/bin/bash R610 server that was booted from a Dell configured to boot using an iSCSI image; as # Compellent Storage Center SAN. The volume a result, there is no need to use the exact # ********************************* # containing the persona was replicated to the same hardware that is used at the main site, # (C) 2011 Dell disaster recovery site in Dell Compellent and for this scenario there was no need to # Remote Instant Replay. Both sites were use Fibre Channel hardware at the remote # ********************************* connected using a Layer 3 network using site. At the main site, the persona runs on a Dell PowerConnect™ 6224 switches. physical PowerEdge R610 server, whereas SDK=/opt/dell/aim/bin/sdk Following a simulated disaster, the at the remote site a server running ESX 4.1 ACCOUNT=admin PASS=admin replicated data for the volumes was is used to boot the persona on an AIM- SCRIPT=$1 promoted to boot volumes on the disaster managed virtual machine. recovery site; AIM then configured the if [ "$SCRIPT” == "" ]; then persona to boot on a VMware ESX 4.1–based Easily testing a disaster recovery process echo "Usage: $0 [script filename]" virtual machine. The configuration at both To simulate a failure at the main site, either exit 1 fi sites consisted of the following components: the server can be powered off or the persona can be stopped from the Dell AIM echo "==========================" • ESX virtual machine running Dell AIM console. The first step following the disaster echo "DELL AIM SDK wrapper" release 3.4.1 or failure is to get to the data restoration echo "Running script $SCRIPT" • Dell Compellent Series 40 controller point (see Figure 1). Administrators can echo "==========================" • A 3.5-inch Serial Attached SCSI (SAS) use the Instant Validation and Recovery echo $SDK account=$ACCOUNT