Effects of virtualization and cloud computing on data center networks

ManualsBrandsHP ManualsComputer AccessoriesHP Virtual Connect 1/10Gb-F Ethernet Module for c-Class BladeSystem

Effects of virtualization and cloud computing on data

center networks

Technology brief

Introduction ......................................................................................................................................... 2

Changing business applications ............................................................................................................ 3

Server virtualization .......................................................................................................................... 3

Client virtualization .......................................................................................................................... 4

Cloud applications ........................................................................................................................... 6

Mobile access devices ...................................................................................................................... 7

Limitations of a hierarchical networking structure ..................................................................................... 7

STP limitations ................................................................................................................................. 7

Oversubscription .............................................................................................................................. 7

Port Extension technology .................................................................................................................. 8

Latency ........................................................................................................................................... 9

Practical solutions for optimizing E/W traffic flow ................................................................................... 9

Identify your traffic bottlenecks ........................................................................................................... 9

Virtual switch architectures ................................................................................................................ 9

EVB architectures—VEPA and VEB ................................................................................................... 10

HP Virtual Connect ......................................................................................................................... 12

HP Intelligent Resilient Framework .................................................................................................... 12

HP IRF with HP Virtual Connect technology ........................................................................................ 13

Conclusion ........................................................................................................................................ 15

For more information .......................................................................................................................... 16

Summary of content (16 pages)

PAGE 1
Effects of virtualization and cloud computing on data center networks Technology brief Introduction ......................................................................................................................................... 2 Changing business applications ............................................................................................................ 3 Server virtualization............................................................................................................
PAGE 2
Introduction Most data centers today have a three- or four-tier hierarchical networking structure. It consists of access layer switches, aggregation switches, and core switches (Figure 1). Three-tier networking architectures were designed around client-server applications and single-purpose application servers.
PAGE 3
This paper won’t answer all your questions about the future of data center networks, but it will identify some industry trends and present some possible solutions.
PAGE 4
Table 2: Changing realities of VMs in x86 environments. Early deployments 2011 and beyond Consolidate two or three VMs per physical server 10-50+ VMs per server Network bandwidth could be easily shared by a few VMs Higher network bandwidth requirements driven by: Greater VM density per physical server More powerful CPU-memory systems VM mobility VM operates statically.
PAGE 5
Figure 2: Architectural overview of VDI with blade servers, storage, and HP Virtual SAN Appliance (VSA) included for the infrastructure. For example, a VDI could let you access a device based on a Microsoft Windows Vista OS, leave for the evening, and come back the next workday to a Microsoft Windows 7-based device—with all your data, customized desktop settings, and customized application settings intact.
PAGE 6
Figure 3: When using a VDI configuration Virtual Connect technology, only a small amount of production (protocol) and management traffic exit the Virtual Connect domain, thus optimizing the E/W traffic flow. Cloud applications Enterprise businesses are moving beyond server virtualization and VMs to embrace cloud-computing environments.
PAGE 7
Distributing storage, distributing databases across multiple servers, sending requests to multiple servers, and accumulating the responses are all E/W traffic intensive. For example, consider how you plan a vacation. You visit the dynamic travel website of your choice and enter your variable data (when you want to travel, where, whether you need a hotel, flight, or a car).
PAGE 8
file block sizes. If your network is oversubscribed, your ability to do live migrations might also be compromised because of the large bandwidth capabilities required. Oversubscription can also lead to requirements for controlling traffic with QoS mechanisms such as enhanced transmission selection, minimum bandwidth guarantees, and maximum rate limits. Most of these mechanisms are manual processes and require a substantial amount of management.
PAGE 9
Latency In many cases, latency may be more of a challenge than oversubscription and raw bandwidth. As pointed out in the “Changing Business Applications” section, as businesses need to supply immediate, context-sensitive information to end users (remember that travel website on page 7?), latency and application responsiveness are driving network designs. Traditional hierarchical and newer architectures like the fabric extension technology require more network hops and increase latency.
PAGE 10
Figure 5: vSwitches do a good job of efficiently routing internal VM-to-VM traffic. However, there are some limitations to a vSwitch: • It moves the control point for networking infrastructure into the domain of the server administrator. This management stack is typically a component of the server-based hypervisor tool aimed at system and virtualization administrators. As such, vSwitch management generally does not integrate with existing external physical network policy and management tools.
PAGE 11
Figure 6: VEPA sends all traffic to the adjacent physical switch. VM Edge Switch Edge Virtual NIC External Network VM VM L2 net(s) EVB VM VM Physical Server Server Edge Physical NIC Advantages of VEPA include: • Moves the VM connection control point into the edge physical switch (ToR or EoR). VEPA leverages existing investments made in data center edge switching. Administrators can manage the edge network traffic using existing network security policies and tools.
PAGE 12
Figure 7: Multichannel capabilities let vSwitch (VEB) and VEPA modes co-exist in the same server platform. HP Virtual Connect One of the ways to optimize the server edge for E/W traffic flow is by implementing HP Virtual Connect technology. Virtual Connect is a set of interconnect modules and embedded software for HP BladeSystem c- Class enclosures that provides server-edge and I/O virtualization.
PAGE 13
IRF lets you create large network fabrics with multiple switches at a single layer (access, distribution, or core) that operate and appear logically as a single switch. You can combine as many as eight HP networking stackable switches or up to four HP networking chassis switches to create a single, logical switch comprised of hundreds or even thousands of 1-GbE or 10-GbE switch ports.
PAGE 14
Figure 8: HP IRF technology can combine with Virtual Connect technology to flatten the L2 network.
PAGE 15
If you use the HP 12518 switch as shown in Figure 8, you can have up to 248 non-blocking 10 Gb/s ports (assuming 4 ports per switch for IRF and 4 ports per switch for uplinks). Each BladeSystem c7000 enclosure supports up to 16 servers. You only need two VC FlexFabric modules to connect all 16 servers to your LAN and SAN.
PAGE 16
For more information Visit the URLs listed below if you need additional information. Resource description Web address Cloud Computing for dummies, HP edition www.ingrammicro.com/visitor/servicesdivision/cloudcom putingfordummies.pdf “Reducing network complexity, boosting performance with HP IRF technology” http://h20195.www2.hp.com/v2/GetPDF.aspx/4AA29402ENW.pdf HP networking blog, “Simplifying data center architecture,” 7/13/11 http://h30507.www3.hp.