Dell EMC Storage Systems Product Guide for the metro node appliance 7.
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Contents Figures..........................................................................................................................................5 Tables........................................................................................................................................... 6 Chapter 1: Preface.........................................................................................................................7 Chapter 2: Introducing metro node..................................
Metro node Metro HA................................................................................................................................................ 29 Metro HA (without cross-connect)........................................................................................................................ 29 Metro HA with cross-connect..................................................................................................................................
Figures 1 Metro node active-active.........................................................................................................................................9 2 Metro node family: Local and Metro....................................................................................................................10 3 Configuration highlights..........................................................................................................................................
Tables 6 1 Typographical conventions...................................................................................................................................... 7 2 General metro node use cases and benefits...................................................................................................... 14 3 Types of data mobility operations........................................................................................................................
1 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.
Table 1. Typographical conventions (continued) ● Commands and options Monospace italic Used for variables. Monospace bold Used for user input . [] Square brackets enclose optional values. | Vertical bar indicates alternate selections - the bar means "or". {} Braces enclose content that the user must specify, such as x or y or z. ... Ellipses indicate nonessential information omitted from the example .
2 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 the data that is on storage arrays to create dynamic, distributed, and highly available data centers. Use metro node to: ● Move data non-disruptively between Dell EMC storage arrays and non-Dell EMC storage arrays without any downtime for the host.
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.
Federation allows transparent data mobility between arrays for simple, fast data movement and technology refreshes. ● Standardizes LUN presentation and management using simple tools to provision and allocate virtualized storage devices. ● Improves storage utilization using pooling and capacity aggregation across multiple arrays. ● Increases protection and high availability for critical applications. Mirrors storage across mixed platforms without host resources.
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. Metro node provides storage federation for operating systems and applications that support clustered file systems, including both physical and virtual server environments with VMware, ESX, and Microsoft Hyper-V.
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. VPlexcli The VPlexcli supports all metro node operations. The CLI is divided into command contexts: ● Global commands are accessible from all contexts.
3 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.
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. No change in volume identifiers eliminates application cut over.
Table 3. Types of data mobility operations Device Moves data from one device to another device (within a cluster and across clusters). 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.
4 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 Online Help for the metro node appliance 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.
5 Integrity and resiliency This chapter describes how the high availability and the redundancy features of metro node provide robust system integrity and resiliency.
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 coherency is maintained for all reads and writes. As you add more directors to the nodes, you get the added benefits of more cache, increased processing power, and more performance.
￭ If half of the operational directors with quorum fail, then the remaining directors will check the operational status of the failed directors over the management network and remain alive. 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.
Logging volumes also track changes during loss of a volume when that volume is one mirror in a distributed device. 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.
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.
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.
Figure 14. High level metro node Witness architecture Metro node Metro HA Metro node Metro High Availability (HA) configurations consist of a metro node Metro system deployed in conjunction with metro node Witness. There are two types of Metro HA configurations: ● Metro node Metro HA can be deployed in places where the clusters are separated by 5 ms latency RTT or less.
Metro HA with cross-connect Metro node Metro HA with cross-connect (front end ports of metro node are cross-connected) can be deployed where the metro node clusters are separated by 1 ms latency RTT or less. Metro node Metro HA combined with cross-connect eliminates RTO for most of the failure scenarios.
Table 4. How metro node Metro HA recovers from failure (continued) Failure description Failure handling Inter-cluster link failure ● If the cross-connects use different physical links from those used to connect the metro node clusters, applications are unaffected. Every volume continues to be available in one data center or the other. ● If the cross-connect links use the same physical links as those used to connect the metro node clusters, an application restart is required.
Higher availability Combine metro node Witness with VMware and cross cluster connection to create even higher availability. 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.
6 Software and upgrade This chapter describes the 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 5. 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.
