Dell EMC Storage Systems Product Guide for PowerStore and Unity XT metro node feature Version 7.
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Contents Figures..........................................................................................................................................5 Tables........................................................................................................................................... 6 Preface......................................................................................................................................... 7 Chapter 1: Introducing metro node............................
Metro node Metro Hardware......................................................................................................................................... 29 Chapter 5: Software and upgrade................................................................................................30 Metro node OS.................................................................................................................................................................. 30 Non-disruptive upgrade (NDU).........
Figures 1 Metro node active-active.........................................................................................................................................9 2 Metro node family: Local and Metro....................................................................................................................10 3 Configuration highlights..........................................................................................................................................
Tables 6 1 Typographical conventions...................................................................................................................................... 8 2 General metro node use cases and benefits...................................................................................................... 14 3 Types of data mobility operations........................................................................................................................
Preface As part of an effort to improve its product lines, Dell EMC periodically releases revisions of its software and hardware. Therefore, some functions described in this document might not be supported by all versions of the software or hardware currently in use. The product release notes provide the most up-to-date information on product features. Contact your Dell EMC technical support professional if a product does not function properly or does not function as described in this document.
NOTE: Presents information that is important, but not hazard-related. Typographical conventions Dell EMC uses the following type style conventions in this document: Table 1.
1 Introducing metro node This chapter introduces the metro node feature. Topics: • • • • • Metro node overview Metro node product family Metro node hardware platforms Configuration highlights Management interfaces Metro node overview Metro node virtualizes data that is on storage arrays to create dynamic, distributed, and highly available data centers.
Metro node offers the following unique innovations and advantages: ● Metro node distributed/federated virtual storage enables new models of application and Data Mobility. Metro node is optimized for virtual server platforms (VMware ESX, Hyper-V, Oracle Virtual Machine, AIX VIOS). Metro node can streamline or accelerate transparent workload relocation over distances, including moving virtual machines.
Deploy metro node Local within a single data center. Metro node Metro Metro node Metro consists of two metro node clusters connected by inter-cluster links with not more than 10ms Round Trip Time (RTT). metro node Metro: ● Transparently relocates data and applications over distance, protects your data center against disaster. Manage all of your storage in both data centers from one management interface. ● Mirrors your data to a second site, with full access at near local speeds.
HP, Oracle (Sun), Microsoft, Linux, IBM Oracle, VMware, Microsoft Brocade, Cisco VPLEX Brocade, Cisco HP, Oracle (Sun), Hitachi, HP (3PAR), IBM, EMC Figure 3. Configuration highlights Metro node conforms to established world wide naming (WWN) guidelines that can be used for zoning. It also supports Dell EMC storage and arrays from other storage vendors, such as HDS, HP, and IBM.
Figure 4. Claim storage using the GUI (for HTML5) The UI supports most of the metro node operations, and includes Dell EMC Online help for metro node to assist new users in learning the interface. Metro node operations that are not available in the GUI, are supported by the Command Line Interface (CLI), which supports full functionality. Metro node CLI The metro node CLI supports all metro node operations. The CLI is divided into command contexts: ● Global commands are accessible from all contexts.
2 Metro node use cases This chapter describes the general features, benefits, and the important use cases of metro node. Topics: • • • General use cases and benefits Mobility Availability General use cases and benefits The following table summarizes the general metro node use cases and their benefits. Table 2. General metro node use cases and benefits General use cases Benefits Mobility ● Migration: Move data and applications without impact on users.
MOBILITY Cluster A Cluster B ACCESS ANYWHERE Move and relocate VMs, application, and data over distance Figure 5. Moving data with metro node The source and target arrays can be in the same data center (metro node Local) or in different data centers separated by up to 10ms (metro node Metro). The source and target arrays can be heterogeneous. When you use metro node to move data, the data retains its original metro node volume identifier during and after the mobility operation.
Table 3. Types of data mobility operations (continued) Batch Moves data using a migration plan file. Create batch migrations to automate routine tasks. ● Use batched device migrations to migrate to dissimilar arrays and to migrate devices within a cluster and between the clusters in a metro node Metro configuration.
Virtual Volume Array A Array B Array C VPLX-000380 Figure 6. Metro node technology refresh Because the virtual machine is addressing its data to the abstracted virtual volume, its data continues to flow to the virtual volume without any need to change the address of the data store. Although this example uses virtual machines, the same is true for traditional hosts.
Cluster A ACCESS ANYWHERE Cluster B X Maintain availability and non-stop access by mirroring across locations. Eliminate storage operatios nfrom failover. Figure 7. High availability infrastructure example Metro node redundancy provides reduced Recovery Time Objective (RTO) and Recovery Point Objective (RPO). Because metro node AccessAnywhere mirrors all data, applications continue without disruption using the back-end storage at the unaffected site.
3 Features in metro node This chapter describes the specific features of metro node. Topics: • • • • • Metro node security features ALUA Provisioning with metro node Performance monitoring Notification Metro node security features The operating systems of the metro node management server and the directors are based on a Novell SUSE Linux Enterprise Server 15 SP1 distribution.
● Explicit ALUA - The storage processor changes the state of paths in response to commands (for example, the Set Target Port Groups command) from the host (the metro node backend). The storage processor must be explicitly instructed to change a path’s state. If the active/optimized path fails, metro node issues the instruction to transition the active/non-optimized path to active/ optimized. There is no need to failover the LUN.
The unmap feature reclaims the unused VMFS blocks by removing the mapping between the logical blocks and the physical blocks. This essentially removes the link between a logical block and a physical block that has unknown or unused resources. Performance monitoring Metro node performance monitoring provides a customized view into the performance of your system. You decide which aspects of the system's performance to view and compare.
Figure 10. Unisphere Performance Monitoring Dashboard - sample chart (for UI) For additional information about the statistics available through the Performance Monitoring Dashboard, see the Dell EMC Unisphere for metro node online help available in the metro node UI. Performance monitoring using the CLI The CLI supports current load monitoring, long term load monitoring, object base monitoring, and troubleshooting monitoring.
4 Integrity and resiliency This chapter describes how the high availability and the redundancy features of metro node provide robust system integrity and resiliency. Topics: • • • • • • • • About metro node resilience and integrity Site distribution Cluster Metadata volumes Backup metadata volumes Logging volumes High availability and metro node hardware Metro node Metro Hardware About metro node resilience and integrity With metro node, you get true high availability.
Data center A Data center B Cluster file system Director 1-1-B Director 1-1-A Director 2-1-A Director 2 -1-B Engine 1 Engine 1 Virtual Volume Virtual Volume VPLX-000394 Figure 11. Path redundancy: different sites Cluster A metro node is a true cluster architecture. That is, all components are always available and I/O that enters the cluster from anywhere can be serviced by any node within the cluster, while cache and coherency is maintained for all reads and writes.
After recovering from this failure, a cluster can tolerate further similar director failures until only one director is remaining. In a single engine cluster, a maximum of one director failure can be tolerated.
CAUTION: If no logging volume is accessible, then the entire leg is marked as out-of-date. A full resynchronization is required once the leg is reattached. The logging volumes on the continuing cluster experience high I/O during: ● Network outages or cluster failures ● Incremental synchronization When the network or cluster is restored, metro node reads the logging volume to determine what writes to synchronize to the reattached volume. There is no I/O activity during normal operations.
Director 1-1-A Director 1-1-B Engine 1 Virtual Volume VPLX-000376 Figure 12. Path redundancy: different ports Combine multi-pathing software plus redundant volume presentation for continuous data availability in the presence of port failures. Back-end ports, local COM ports, and WAN COM ports provide similar redundancy for additional resilience. Each director can service I/O for any other director in the cluster due to the redundant nature of the global directory and cache coherency.
Director 1-1-A Director 1-1-B Engine 1 Virtual Volume VPLX-000392 Figure 13. Path redundancy: different directors Management server Each metro node server has embedded management server. You can manage both clusters in a metro node Metro configuration from a single management server. The management server acts as a management interfaces to other metro node components in the cluster. Redundant internal network IP interfaces connect the management server to the public network.
Metro node Metro Hardware To ensure continuous availability across multiple data centers in a metro region, metro node Metro provides an ideal solution with the option of Metro over IP (MetroIP). Metro node use a metro node Metro with a 10 Gb Ethernet.
5 Software and upgrade This chapter describes the GeoSynchrony software that runs on the metro node hardware. Topics: • • Metro node OS Non-disruptive upgrade (NDU) Metro node OS Metro node OS is the operating system that runs on the metro node hardware.
Table 4. Metro node OS AccessAnywhere features (continued) Feature Description and considerations Global Visibility The presentation of a volume from one metro node cluster where the physical storage for the volume is provided by a remote metro node cluster. Considerations: Use Global Visibility for AccessAnywhere collaboration between locations.
Glossary A AccessAnywhere The breakthrough technology that enables metro node clusters to provide access to information between clusters that are separated by distance. active/active A cluster with no primary or standby servers, because all servers can run applications and interchangeably act as backup for one another. active/passive A powered component that is ready to operate upon the failure of a primary component. Active Directory A directory service included in most Windows Server operating systems.
C cache coherency Managing the cache so that data is not lost, corrupted, or overwritten. With multiple processors, data blocks may have several copies, one in the main memory and one in each of the cache memories. Cache coherency propagates the blocks of multiple users throughout the system in a timely fashion, ensuring that the data blocks do not have inconsistent versions in the different processors caches.
detach rule Predefined rules that determine which cluster continues I/O when connectivity between clusters is lost. A cluster loses connectivity to its peer cluster due to cluster partition or cluster failure. Detach rules are applied at two levels; to individual volumes, and to consistency groups. If a volume is a member of a consistency group, the group detach rule overrides the rule set for the individual volumes.
F failover Automatically switching to a redundant or standby device, system, or data path upon the failure or abnormal termination of the currently active device, system, or data path. fault domain A set of components that share a single point of failure. For metro node, the concept that every component of a highly available system is separated, so that if a fault occurs in one domain, it will not result in failure in other domains to which it is connected.
host bus adapter (HBA) An I/O adapter that manages the transfer of information between the host computers bus and memory system. The adapter performs many low-level interface functions automatically or with minimal processor involvement to minimize the impact on the host processors performance. I infiniband A networking standard used for passing data between and among computers. The VS6 hardware uses this protocol for the intra-cluster communication.
local device A combination of one or more extents to which you add specific RAID properties. Local devices use storage from only one cluster. logical unit number (LUN) Virtual storage to which a given server with a physical connection to the underlying storage device may be granted or denied access. LUNs are used to identify SCSI devices, such as external hard drives that are connected to a computer. Each device is assigned a LUN number which serves as the device's unique address.
Non-distributed consistency groups Transfer data through one primary RPA that is designated by the user during group creation. The policies applied by the consistency group can be modified at any time. In the event of RPA failure, groups that transfer data through the failed RPA will move to other RPAs in the cluster. O Open LDAP Open source implementation of the Lightweight Directory Access Protocol (LDAP). P parity checking Checking for errors in binary data.
RecoverPoint Appliance (RPA) Hardware that manages all aspects of data protection for a storage group, including capturing changes, maintaining the images in the journal volumes, and performing image recovery. RecoverPoint cluster All connected RecoverPoint Appliances on both sides of the replication. RecoverPoint site All RecoverPoint entities that are on one side of the replication. Recovery Point Objective (RPO) Recovery Point Objective.
repository volume A volume dedicated to RecoverPoint for each RPA cluster. The repository volume serves all RPAs of the particular RPA cluster and the splitter associated with that cluster. The repository volume stores configuration information about the RPAs and RecoverPoint consistency groups. There is one repository volume per RPA cluster. restore source This operation restores the source consistency group from data on the copy target.
For example, in banking, two withdrawals from a checking account that started at the same time must not overlap; therefore, they are processed synchronously. T throughput 1. The number of bits, characters, or blocks passing through a data communication system or portion of that system. 2. The maximum capacity of a communications channel or system. 3. A measure of the amount of work performed by a system over a period of time. For example, the number of I/Os per day.
write-through mode A caching technique in which the completion of a write request is communicated only after data is written to disk. This is almost equivalent to non-cached systems, but with data protection.
Index A M AccessAnywhere 17 ALUA 19 API 13 architecture 11 audience 7 availability 23 management from clusters 12 Management GUI 12 management server 28 metadata volumes 25 metro node Metro Metro over IP 29 metro node OS 30 migration 16 mirrors 25 mobility 14, 16 monitoring 21, 22 monitoring CLI 22 monitors 22 multi-pathing 23 B back-end load 21 backup metadata volumes 25 Big Data 17 C CAW 22 certificates 19 CLI 13 cluster 11, 24 clusters 12, 23 collaboration 17 command line management 13 comments 7 co
U Unisphere for VPLEX 12 Unisphere GUI 12 Unisphere monitoring tool 21 unmap 20 upgrade 31 user roles 19 V VPLEX hardware 26 VPLEX hardware platforms 11 VPLEX Witness 23 W WAN link load 21 WWN 11
