Resource Library

The Logical Volume Manager (LVM) is a powerful tool for managing storage on Linux servers. This video provides an overview of how LVM works and explores several ways that LVM makes storage management easier and more flexible. Examples include how to expand storage capacity on the fly using LVM and resize2fs, and how to migrate data from local storage to a storage area network (SAN) without downtime using pvmove.

Often, we don't have time to learn the reasons behind the standards we use. But learning what instigated a standard goes a long way toward not only understanding its importance, but also more easily and effectively applying it in your workplace. In this hour-long webinar, Global Knowledge instructor Keith Sorn will discuss common networking standards and explain how they were determined and why they are relevant. He will fill you in on things like why it's important to use proper color-coding standards when making cable and why the length limitations on wired cable are essential. He will also explain new standards, such as power over fiber.

Network Functions Virtualization (NFV) is gaining momentum along with Software-Defined Networking (SDN). This paper examines the history of NFV and explores the prospects for networking to gradually evolve from a hardware-centric approach to a software-driven model. It concludes with an examination of future market implications and how NFV can help organizations to achieve their goals.

Many people believe that cloud computing requires server (or desktop) virtualization. But does it? We will look at using virtualization without cloud computing, cloud computing without virtualization, and then look at using both together. In each case, we'll look at where each deployment might be most useful, some use cases for it and some limitations.

After a review of Software-Defined Networking (SDN) and its close cousin Network Functions Virtualization (NFV), this white paper addresses three main deployment scenarios: SDN without deploying cloud computing, cloud computing without deploying SDN, and deploying cloud computing in conjunction with SDN. We'll look at use cases, when the approach makes sense, and any applicable limitations.

In 2013, VMware announced VMware Virtual SAN (VSAN), which is VMware's native version of Software Defined Storage (SDS). It is simple, easy to setup and managed by user-defined policies. This paper explains VSAN, its basic requirements and how it works.

The technologies examined reduce operational expenses (OpEx), not capital expenses (CapEx) that has traditionally been the focus of virtualization. Many companies implemented virtualization with the goal of saving money in the form of fewer servers to buy with a side benefit of reducing the footprint of the servers and lowering the required power and cooling. Most of the savings were in capital, but do not expect the same with many of the technologies listed here, because some may even require some additional capital expenditures, at least for software, in order to save on the day-to-day operations of IT. The bigger cost in running an IT department is in the OpEx category anyway, so savings there are recurring.

In this report, I've reviewed the 15 most popular certifications according to our more than 12,000 North American respondents to our annual IT Skills and Salary Survey. For each certification, you'll find a brief description, the average salary, and some insight into why it is popular.

Organizations are moving strongly toward Bring Your Own Device (BYOD) access, bringing outsourced activities back in-house, and finding ways to make use of the growing amounts of data flowing in from many new sources such as social media. These factors create an increasing shift in required and desired skills showing up in IT departments. Hiring and salary surveys, such as the 2014 IT Skills and Salary Survey from Global Knowledge and Windows IP Pro, TEKsystems' 2014 Annual IT Forecast, Foote Research Group's 2014 IT Skills and Certifications Pay Index, Computerworld's annual Forecast survey, Robert Half Technology Survey, and information from the US Bureau of Labor Statistics, Futurestep, Mondo, GovLoop, and Dice have presented a developing picture of the IT skills that will be in demand in 2014. Here, in survey order, are the top 10 major skills and why they made the list.

Instructor John Harmon explains subnetting using binary numbers and decimal conversions.

vSphere 5.5 is now available with myriad small improvements such as a faster Web Client, LACP, Autoscale and higher configuration maximums. In addition, there are changes coming such as VSAN, which may be ground-breaking in regard to VM storage of the future. Since the release of vSphere 5.5, they have not yet announced a change to the blueprint for the test. That being the case, I will say, for now, that the VCP-510 test should remain unchanged as well. My goal here is not to reeducate you on everything that you need to know for the test; instead, it is to point out the few changes that might apply in your company or organization.

Instructor John Harmon continues his explanation of subnetting by showing how subnet masks can be used to sub-divide networks.

There are several Wireless LAN Standards, including b, g, and n, which exist in the 2.4 GHz band. These standards need around 20 MHz of radio frequency in order to transmit their signals. In this video, Ben Miller discusses how to pick access points and channels for optimal performance.

Answer? When it is flagged as a retransmission in Wireshark!

VMware vCloud Director fashions the provisioning of the software-defined datacenter layer to allow for a full virtual datacenter deployment within a short period of time. A vCloud consists of many layers and can quickly become a complex architecture. Before any deployment, requirements should be defined so that the vCloud can be designed to offer those services needed. It is imperative to understand the many components of vCloud, how each vCloud construct fits, which allocation models are available, and what network options can be chosen.

The driver behind 802.11n is MIMO, or multiple input multiple output. This video explains how MIMO works to double your channel speed by sending two or more data streams over the same channel.

Traditionally, ITIL and TOGAF professionals have been part of different teams within an organization. Due to the ongoing alignment of business and IT, these professionals now often find themselves on the same team. Because of this crossover, there is a growing trend towards organization of work based on multiple best practice models. 

Are you at a crossroads professionally or looking to start training for a new job? If so, you might want to consider pursuing network administration as a career. Network administrators are responsible for maintaining computer hardware and software systems that make up a computer network, including maintaining and monitoring active data networks, converged infrastructure networks, and related network equipment.

Global Knowledge Product Manager Tori Easterly discusses the benefits of our Understanding Networking Fundamentals course.

Multiplexing is the technology that is able to combine multiple communication signals together in order for them to traverse an otherwise single signal communication medium simultaneously. Multiplexing can be applied to both analog and digital signals. A benefit of using multiplexing, or muxing, is reducing the physical hardware cost for expensive dedicated network communication segments, such as copper or fiber cables.

Session Initiation Protocol (SIP) is an internet signaling protocol, developed by the IETF (starting in 1996), for establishing, maintaining, and tearing down sessions between a variety of real-time media, including voice, video, and chat. SIP allows endpoints to locate other endpoints, whether stationary or mobile. SIP doesn't have to worry about transporting voice or video as Real Time Transport Protocol (RTP) takes care of that. It also relies on Session Description Protocol (SDP) to negotiate capabilities and codecs. SIP does not provide a Directory Service or Authentication, but it does work with services such as LDAP or RADIUS. SIP is only concerned with signaling. This white paper is going to look at the way SIP is used in the converged Unified Communications environment.

A local area network (LAN) provides a path of communication, allowing the delivery of packets of data, voice, or video originating from the sender (logical source address) to the receiver (logical destination address). Ethernet is the most common LAN used. As you start to learn about networking, remember that communication and the movement of large numbers, whether it is people, cars, mail, or network traffic, have a commonality. Everything you know and use in your daily life can be compared to the way traffic moves.

The OSI model is a conceptual tool used to discuss and describe network functions. The use of a standard reference model is essential to communicating ideas as well as creating new technologies. It is a good idea to be familiar with the OSI model, the features assigned to each layer, and examples of common protocols or technologies associated with the OSI layers.

One of the most important steps in mastering a new technology is learning the associated terminology or vocabulary. In the IT field, this can be a very challenging step, as much of the terminology is often used inconsistently. This white paper defines the terminology associated with IT virtualization. It is mainly vendor-agnostic, but it does provide some vendor-specific terms, product names, and feature names used by VMware, Citrix, and Microsoft.

The utility that many senior VMware administrators rely on to address performance and troubleshooting issues is the built-in utility called ESXTOP. The tool has been built in to the hypervisor, and can be used in both ESXi and the old ESX host. The first tool many VMware Administrators rely upon is esxtop, to check real-time performance on an ESXi host using a command-line tool such as ssh to start the esxtop CLI utility. This paper will introduce and demonstrate how to start and use esxtop, specifically looking at the CPU fields. In addition, we will cover information that can be used to help with performance issues of the CPU. The esxtop utility is an excellent tool to use when you want to observe an individual ESXi host's performance.

The OSI model is a conceptual tool used to discuss and describe network functions. The use of a standard reference model is essential to communicate ideas as well as create new technologies. It is a good idea to be familiar with the OSI model, the features assigned to each layer, and examples of common protocols or technologies associated with the OSI layers.

Diane Teare, Global Knowledge's Cisco Course Director, discusses the advantages to taking our CCNA Boot Camp.

Resource Pools are often misunderstood, disliked, and untrusted by vSphere Administrators. However, resource pools can be very useful tools for administrators who want to configure resource management without having to individually configure each VM. This leads to the administrator’s desire to explore the proper usage of resource pools.

This white paper has three main goals. The first is to generate a better understanding of the cloud in both the business and IT communities. The second is to describe the major components of vCloud and the virtual datacenters they provide. The third is help businesses visualize and understand how vClouds could be beneficial in addressing their specific IT needs.

This vSphere Essentials white paper will give you a basic understanding of some of the concerns or planning points to consider as you get ready to deploy vSphere in your organization. This is a glimpse into some of the essential things to consider for implementing vSphere. This will focus on some of the basics that vSphere administrators run into when installing the latest features and not realizing they still have some older versions implemented.

One of the many useful features of tunneling is to carry non-IP traffic across an IP network, and this is still the case when dealing with IPv6 traffic. This transition mechanism makes use of a configured tunnel to transport IPv6 over a native IPv4 network, which may consist of two sites or more. Unlike the previous transition mechanisms, tunneling is not monolithic; while the basic principles may be similar, the operations are different. The following chart gives a breakdown of the current, major tunneling types in use, particularly in a Cisco environment:

As with the adoption of any new technology, the move from IP version 4 to IP version 6 will take a number of years to complete. During that transition phase, various mechanisms will be necessary to continue support of the older protocol as the newer gains widespread momentum. In addition, there has been some evolution even within the availability of these mechanisms, some of which have already passed from general use into deprecated status. Network engineering professionals already proficient in the use of IPv6, as well as the available coexistence mechanisms, will undoubtedly stay in high demand throughout this process.

The STP (Spanning Tree Protocol) standard (IEEE 802.1d) was designed when the recovery after an outage could wait a minute or so and be acceptable performance. With Layer 3 switching in LANs, switching began to compete with routers running protocols because they are able to offer faster alternate paths. Rapid Spanning Tree Protocol (RSTP or IEEE 802.1w) brought the ability to take the twenty seconds of waiting for the Max Age counter plus fifteen seconds of Listening plus fifteen seconds of Learning or fifty seconds down to less than one second for point-to-point connected and edge switches and six seconds for root switches.

In a recent post, I gave an overall description of a service portfolio and the key components of a portfolio. Here, I will describe how a cloud services provider might implement an ITIL service portfolio. A cloud services provider will regularly have a set of services under development, a set of service in live operation, and a set of services that are retired.

This short example illustrates basic VLAN operation. Examining VLANs in a large-scale installation can show the full benefits of VLANs. Consider that this is a small portion of a large corporate headquarters with 5,000 devices connected in a 20 building campus.

In 1998, the Internet Engineering Task Force (IETF) released RFC 2460, outlining the technical specifications of IPv6, which addressed the shortcomings of the aging IPv4 protocol. As with any evolution of technology, new elements exist in the protocol that may seem strange and unfamiliar. This certainly includes address representation, space, and so forth, but also includes a number of different types of addresses as well. A subset of these new addressing types has corresponding types in IPv4, but many will seem significantly different. The purpose of this white paper is to examine addressing classifications in detail and outline their functions within the context of the protocol.

If you are upgrading to ESXi 5.1, there are some important facts that you should consider first. Upgrading involves many stages and processes that must be performed in a specific order. Many of these processes are one-way and do not provide a "back button." If you do not use care and consideration in your upgrade plan, you could possibly lose important data and configuration; and potentially even lose contact with your servers.

Depending on the switch vendor, the exact steps will vary on how to set up and configure VLANs on a switch. For the network design shown, the general process for setting up VLANs on the switch is:

Now that the network is installed, each switch has a bridge ID number, and the root switch has been elected, the next step is for each switch to perform a calculation to determine the best link to the root switch. Each switch will do this by comparing the path cost for each link based on the speed. For paths that go through one or more other switches, the link costs are added. The switch compares this aggregate value to the other link costs to determine the best path to the root switch.

That depends on their configurations. For example: While it makes very good sense to include redundant physical links in a network, connecting switches in loops, without taking the appropriate measures, will cause havoc on a network. Without the correct measures, a switch floods broadcast frames out all of its ports, causing serious problems for the network devices. The main problem is a broadcast storm where broadcast frames are flooded through every switch until all available bandwidth is used and all network devices have more inbound frames than they can process.