What you are going to learn Cisco Nexus 7000 Series Switches and Ethernet Storage
The simplicity, resilience, and cost-effectiveness of Ethernet allow it to complement traditional Fiber Channel networks, making IP storage solutions increasingly popular in enterprise deployments. IP-based storage solutions provide flexible, low-cost options when implementing SAN.
The new standards give data center architects options to design new data centers and optimize existing facilities. These new technologies allow different storage protocols to coexist on the same infrastructure, dramatically increasing the utilization of installed equipment and reducing the need to duplicate infrastructure. Critical components of the data center network, Cisco Nexus 7000 Series Switches provide a solid foundation for building a converged network. With support for multiple storage protocols, fewer management points, a small network size, and an optimized deployment model, the Cisco Nexus 7000 Series can deliver lower operating expenses.
Challenges of creating a successful data center network
There are many challenges to implementing a successful data center. Architects must consider how to handle not only the existing data traversing the network but also how to handle growth over time. Plus, they care about protecting data from corruption and unauthorized access, now and in the future.
These concerns lead to several questions:
- How does the administrative team manage all these systems, as well as the information that runs through them?
- How can data be securely isolated to address security and resiliency concerns?
- How does a successful data center manage not only technology (both current and new), but also its security and growth over time?
This document discusses how Cisco data center innovations, such as the Cisco Nexus 7000 Series Switches and Cisco NX-OS Software, address these questions and create flexible yet robust multiprotocol storage networks that provide:
- Highly aggregated bandwidth
- Clean and deliberate segregation of storage traffic.
- Data security and authentication
- High availability and data resistance.
- Consolidation of multiprotocol I/O for comprehensive platform management
As business needs change and additional demands are placed on data centers, today’s IT managers and operators are looking for ways to get additional value from their investments. This document examines each of these features and helps you identify how the Cisco Nexus 7000 Series can provide that value both now and in the future.
Higher available bandwidth and low data latency improve the performance of IP storage solutions such as Small Computer System Interface over IP (iSCSI) and Network Attached Storage (NAS). However, the Cisco Nexus 7000 series offers additional Layer 2 solutions, such as Cisco FabricPath and virtual PortChannel (vPC) technology, that enable data center designers to build highly scalable IP storage networks.
Traditionally, Layer 2 network designs have required loop avoidance and the technology that achieves this is the Spanning Tree Protocol. With the spanning tree protocol, redundant links in a fully meshed network are eliminated until there is only one path for each host on the network. Network designers purposely create redundant links to increase bandwidth and endurance. The spanning tree protocol, by creating a single path, limits available bandwidth and prevents operators from implementing complex and scalable network architectures.
Additional features available on the Cisco Nexus 7000 Series allow all links to operate in active mode, while still avoiding loops. These features allow the operator to use all available aggregate bandwidth and load sharing traffic between all available links. The two features that enable this bandwidth utilization are vPC and Cisco FabricPath.
Virtual PortChannel is a Cisco Layer 2 technology that addresses the need to use all the bandwidth provided by redundant links between different switching devices. In essence, a vPC groups a series of hot links and represents them as a single link (PortChannel) to the spanning tree protocol. In a traditional PortChannel, the PortChannel can be between only two devices. However, in a vPC, the vPC can span more than two devices as the source or destination of the links. This capability enables a loop-free network while achieving link-based redundancy as PortChannel remains active as long as at least one link member is available and active. The Cisco vPC implementation does not impose any limitations on the location of the ports that belong to the vPC, allowing them to be spread across multiple line cards. Additionally, a vPC can be linked to multiple devices, further spreading the traffic load and adding redundancy at the switch (hardware) level.
Cisco FabricPath is Cisco’s innovative Layer 2 Multipath (L2MP) protocol available on Cisco NX-OS. Here a link-state protocol is used to build a routing table of all relevant Layer 2 endpoints at the access layer. Cisco FabricPath uses all available links when creating its Layer 2 routing table, allowing network designers to create an Equal Cost Multipath (ECMP) data plane in which traffic can be load balanced across up to 16 routes. This approach dramatically increases the cross-sectional bandwidth available at the access layer and prevents blockage while allowing path resiliency to be built through the Layer 2 domain.
Using vPC or Cisco FabricPath on the Cisco Nexus 7000 Series at the access layer is extremely beneficial for any IP storage deployment because it increases the aggregate network bandwidth available to servers while providing a flexible yet flexible access network. high availability. This type of implementation provides better convergence because the network adjusts to changes in link availability. Removing the spanning tree protocol from the network reduces the number of hops at this layer and creates a more deterministic path to servers. These innovative technologies available in the Cisco Nexus 7000 Series benefit all IP storage traffic by increasing the efficiency of the data path at the access layer.
Storage traffic segregation
Storage network architects have traditionally isolated storage traffic from other LAN traffic to reduce collateral damage and help ensure the performance of storage traffic. Historically, this was accomplished by dedicating a VLAN to IP storage traffic. However, on Cisco Nexus 7000 Series switches, the Virtual Device Context (VDC) feature allows a switch to be virtualized into multiple logical switches, each with its own set of independent runtime settings and processes. Each VDC operates as an independent switch. Figure 3 shows the VDC model on an IP storage network.
Each VDC can contain its own unique, independent set of VLANs and Virtual Route Forwarding (VRF) instances. Multiple interfaces can belong to a single VDC, allowing the data forwarding plane to be independent and virtualized. Each VDC has a separate configuration, routing processes, and process memory. Additionally, security and management policies can be set per VDC. This switch isolation allows iSCSI and NAS traffic, the two most common forms of IP storage traffic, to be separated from other LAN traffic and controlled or managed accordingly.
As shown in Figure 3, each VDC is isolated from the others. This isolation allows storage traffic to be unaffected by failures or changes in other parts of the system (or other VDCs). In addition, a separate management plane for configuration and debugging improves the operator’s ability to control certain resources on the network, without being affected by actions taken in other parts of the network despite sharing the same physical resource. This increased level of redundancy and manageability available in the Cisco Nexus 7000 Series is beneficial for any IP storage network.
Data security and authentication
In addition to the management isolation that VDCs provide, the Cisco Nexus 7000 Series platform offers other management and security features that make it particularly suitable for IP storage deployments.
Role-based access control
Cisco NX-OS allows administrators to restrict and control access to a specific group of users. Users, defined by role, are allowed or denied access to network resources, improving network security. This feature, called role-based access control (RBAC), allows administrators to be in charge of a specific VLAN without having access to or visibility of other VLANs. Storage network operators can define separate policies that create much stricter access rules for IP storage infrastructure and resources, and provide separate access policies for their Ethernet resources.
Cisco Nexus 7000 Series Switches are fully-featured, manageable, secure, highly available, and rugged Ethernet switches that give data center designers and administrators the flexibility to deploy any storage device anywhere on the network. In particular, IP storage devices benefit from the higher cross bandwidth, segregation of storage traffic, and high availability that these switches provide. These features allow data center designers to implement IP storage arrays for mission critical applications. Additionally, by enabling I/O traffic consolidation, this platform enables administrators to reduce their overall CapEx and OpEx while taking advantage of mature and future Ethernet features (40 and 100 Gbps Ethernet). This flexibility enables the Cisco Nexus 7000 Series to dynamically meet the changing business and performance requirements of the data center.
In particular, the implementation of the Cisco Nexus 7000 series as Ethernet storage director switches meets and exceeds the requirements for a successful data center.