<CHAPTER ID="2"><TITLE>Connecting the Switch Block</TITLE>
<CHAPTEROBJECTIVEBLOCK><CHAPTEROBJECTIVETITLE>The CCNP exam topics covered in this chapter include the following:</CHAPTEROBJECTIVETITLE>
<CHAPTEROBJECTIVE>Cable media and the IEEE</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>The differences and benefits of 10BaseT, FastEthernet, and Gigabit Ethernet</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>Connecting and logging in to a set-based switch and an IOS-based switch</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>Setting the hostname, interface descriptions, passwords, and IP addresses of a set-based switch and an IOS-based switch</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>Configuring the duplex and speed of switch interfaces</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>Verifying IP connectivity</CHAPTEROBJECTIVE>
<CHAPTEROBJECTIVE>Deleting the set-based and IOS-based switch configurations</CHAPTEROBJECTIVE></CHAPTEROBJECTIVEBLOCK>
<PARA><DROPCAP>B</DROPCAP>andwidth is now as important as crude oil. Without oil, we have no cars or factories, and basically, the economy stops. Oil is the fuel of the industrial world's economies. And network bandwidth is the oil of the twenty-first century. Without it-or when it's in short supply-our networks come to a grinding halt. If you think we're exaggerating, or you don't agree at all, just try shutting down a part of your network at work and watch the wars begin. Department will turn against department, friend will turn against friend-people will stop at nothing to get their computers up and running on the network, much like the chaos that would result if a Middle Eastern country were to refuse us our oil. Sure, if we have oil but no bandwidth, we can drive our cars and heat our homes, but we wouldn't be able to use the Internet. And without the Internet, we'd have to get into our cars and drive everywhere, among other inconveniences. Not a nice thought. </PARA>
<PARA>So, can we have bandwidth and world peace all at the same time? Yes. By creating a sound, hierarchical network that follows the Cisco three-layer model, you too can be a Nobel laureate at home and on the job. </PARA>
<PARA>This chapter will help you understand the different <KEYTERM>contention media</KEYTERM> available. Contention networks are first come, first served, or what we call Ethernet. This course covers only contention media because it runs at least 50 percent of the networks in the world, if not much more.</PARA>
<SECTION ID="2.1"><TITLE>Cable Media</TITLE>
<PARA><DROPCAP>T</DROPCAP>o know when and how to use the different kinds of cable media, you need to understand what users <EMPHASIS FORMAT="italic">do</EMPHASIS> on the corporate network. The way to find this information is to ask questions. After that, you can use monitoring equipment to really see what is going on inside the network cabling. Before you deploy an application on a corporate network, carefully consider bandwidth requirements as well as latency issues. More and more users need to compete for bandwidth on the network because of bandwidth-consuming applications. Although layer 2 switches break up collision domains and certainly help a congested network if correctly designed and installed, you must also understand the different cable media types available and where to use each type for maximum efficiency. That's where this chapter comes in. </PARA>
<PARA>In this chapter, we'll teach you the basics of Ethernet networking and how to use the various flavors of Ethernet networking in your access, distribution, and core networks. After you have learned about the different Ethernet cable media types, you'll learn how to log in and configure both a set-based switch and an IOS-based switch. The chapter will end with hands-on labs in which you'll connect the switches together and configure them. </PARA>
<SECTION ID="2.1.1" POS="1"><TITLE>The Background of IEEE Ethernet</TITLE>
<PARA>In 1980, the Digital, Intel, and Xerox (DIX) consortium created the original Ethernet. Predictably, Ethernet_II followed and was released in 1984. The standards-setting organization Institute of Electrical and Electronics Engineers (IEEE) termed this the 802 project. The 802 project was initially divided into three groups:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>The High Level Interface (HILI) became the 802.1 committee and was responsible for high-level internetworking protocols and management.</PARA></LISTITEM>
<LISTITEM><PARA>The Logical Link Control (LLC) group became the 802.2 committee and focused on end-to-end link connectivity and the interface between the higher layers and the medium-access-dependant layers.</PARA></LISTITEM>
<LISTITEM><PARA>The Data Link and Medium Access Control (DLMAC) group became responsible for the medium-access protocols. The DLMAC ended up splitting into three different committees:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>802.3 for Ethernet</PARA></LISTITEM>
<LISTITEM><PARA>802.4 for Token Bus </PARA></LISTITEM>
<LISTITEM><PARA>802.5 for Token Ring</PARA></LISTITEM>
</LIST></LISTITEM>
</LIST>
<PARA>DEC, Intel, and Xerox pushed Ethernet, while Burroughs, Concord Data Systems, Honeywell, Western Digital, and later, General Motors and Boeing, pushed 802.4. IBM took on 802.5. </PARA>
<PARA>The IEEE then created the 802.3 subcommittee to come up with an Ethernet standard that happens to be almost identical to the Ethernet_II version of Ethernet. The two differ only in their descriptions of the Data Link layer. Ethernet_II has a Type field, whereas 802.3 has a Length field. Even so, they're both common in their Physical layer specifications, MAC addressing, and understanding of the LLC layer's responsibilities.</PARA>
<NOTE>See <EMPHASIS FORMAT="italic">CCNA: Cisco Certified Network Associate Study Guide</EMPHASIS> by Todd Lammle (Sybex, 2000) for a detailed explanation of Ethernet frame types.</NOTE>
<PARA>Ethernet_II and 802.3 both define a bus-topology LAN at 10Mbps, and the cabling defined in these standards are identical:</PARA>
<RUNINPARA>Segments up to 500 meters using RG8 or 11 at 50 ohms.</RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>10BaseT/UTP</RUNINHEAD>
<RUNINPARA>All hosts connect using unshielded twisted-pair (UTP) cable to a central device (a hub or switch). Category 3 UTP is specified to 10Mbps, category 5 to 100Mbps, category 6 to 155Mbps, and category 7 to 1Gbps.</RUNINPARA></RUNINBLOCK>
<PARA>Ethernet is the most popular type of network in the world and will continue to be so. It is important to understand how hubs and switches work within an Ethernet internetwork.</PARA>
<PARA>By using <KEYTERM>switched Ethernet</KEYTERM> in layer 2 of your network, you no longer have to share bandwidth with the different departments in the corporation. With hubs, all devices have to share the same bandwidth, which can cause havoc in today's networks. </PARA>
<PARA>Remember that layer 2 switches break up collision domains, but the network is still one large broadcast domain. Switched Ethernet has replaced shared hubs in the networking world because each connection from a host to the switch is its own collision domain. Remember that, with shared hubs, the network was one large collision domain and one large broadcast domain, whereas layer 2 switches break up collision domains on each port, but all ports are still considered, by default, to be in one large broadcast domain. Only virtual LANs, covered in <NOBR REF="3">Chapter 3</NOBR>, break up broadcast domains in a layer 2 switched network. </PARA>
<PARA>Switched Ethernet is a good way to dynamically allocate dedicated 10, 100, and 1000Mbps connections to each user. By also running full-duplex Ethernet, you can theoretically double the throughput on each link. In the next sections, we'll discuss how Ethernet is used in your internetwork, the differences between the Ethernet types, and half- and full-duplex. </PARA>
</SECTION>
</SECTION>
<SECTION ID="2.2"><TITLE>Using Ethernet Media in Your Internetwork</TITLE>
<PARA><DROPCAP>I</DROPCAP>n this section, you'll learn the difference between the Ethernet media types and how to use them in your internetworks. We'll cover the following Ethernet types:</PARA>
<PARA><KEYTERM>10BaseT</KEYTERM> stands for 10 million bits per second (Mbps), baseband technology, twisted-pair. This Ethernet technology has the highest install base of any network in the world. It runs the Carrier Sense Multiple Access/Collision Detection (CSMA/CD) protocol and, if correctly installed, is an efficient network. However, if it gets too large and the network is not segmented correctly, problems occur. It is important to understand collision and broadcast domains and how to correctly design the network with switches and routers.</PARA>
<SECTION ID="2.2.1.1"><TITLE>Use 10BaseT at the Access Layer</TITLE>
<PARA>10BaseT Ethernet is typically used only at the access layer, and even then, FastEthernet (100BaseT) is quickly replacing it as the prices for 100BaseT continue to drop. It would be poor design to place 10BaseT at the distribution or core layers. You need transits that are much faster than 10BaseT at these layers. </PARA>
</SECTION>
<SECTION ID="2.2.1.2"><TITLE>Distance</TITLE>
<PARA>The distance that 10BaseT can run and be within specification is 100 meters (330 feet). The 100 meters includes the following:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>Five meters from the switch to the patch panel</PARA></LISTITEM>
<LISTITEM><PARA>Ninety meters from the patch panel to the office punch-down block</PARA></LISTITEM>
<LISTITEM><PARA>Five meters from the punch-down block to the desktop connection</PARA></LISTITEM>
</LIST>
<PARACONTINUED>This doesn't mean that you can't really run more then 100 meters on a cable run; it just is not guaranteed to work. </PARACONTINUED>
</SECTION>
</SECTION>
<SECTION ID="2.2.2"><TITLE>FastEthernet</TITLE>
<PARA><KEYTERM>FastEthernet</KEYTERM> is 10 times faster than 10Mbps Ethernet. The great thing about FastEthernet is that, like 10BaseT, it is still based on the Carrier Sense Multiple Access/Collision Detection (CSMA/CD) signaling. What this means is that you can run 10BaseT and 100BaseT on the same network without any problems. What a nice upgrade path this type of network can give you. You can put all your servers on 10BaseT and upgrade only the clients to 100BaseT if you need to. However, you can't really even buy a PC that doesn't have a 10/100 Ethernet card in it anymore, so you really don't need to worry about compatibility and speed issues from the user's perspective. </PARA>
<SECTION ID="2.2.2.1"><TITLE>Use FastEthernet at All Three Layers</TITLE>
<PARA>FastEthernet works great at all layers of the hierarchical model. It can be used to give high performance to PCs and other hosts at the access layer, provide connectivity from the access layer to the distribution layer switches, and connect the distribution layer switches to the core network. Connecting a server block to the core layer would need, at a minimum, FastEthernet or maybe even Gigabit Ethernet. </PARA>
</SECTION>
<SECTION ID="2.2.2.2"><TITLE>IEEE Specifications for FastEthernet</TITLE>
<PARA>There are two different specifications for FastEthernet, but the IEEE 802.3u is the most popular. The 802.3u specification is 100Mbps over category 3 or 5, twisted-pair (typically just category 5 or 5 plus is used for FastEthernet). The second Ethernet specification, called 802.12, used a different signaling technique, which was more efficient than the CSMA/CD access method. The IEEE passed both methods in June 1995, but because 802.3 Ethernet had such a strong name in the industry, 802.12, also called Demand Priority Access Method (DPAM), has virtually disappeared from the market. As with the Macintosh and NetWare operating systems, it doesn't mean anything if you have a better product; it only matters how you market it.</PARA>
<PARA>The IEEE 802.3u committee can be summarized as follows:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>Provide seamless integration with the installed base</PARA></LISTITEM>
<LISTITEM><PARA>Provide 100BaseT at only two times the cost (or less) of 10BaseT</PARA></LISTITEM>
<PARA>FastEthernet requires a different interface than 10BaseT Ethernet. 10Mbps Ethernet used the Attachment Unit Interface (AUI) to connect Ethernet segments together. This provided a decoupling of the MAC layer from the different requirements of the various Physical layer topologies, which allowed the MAC to remain constant but meant the Physical layer could support any existing and new technologies. However, the AUI interface could not support 100Mbps Ethernet because of the high frequencies involved. 100BaseT needed a new interface, and the MII provides it.</PARA>
<PARA>100BaseT actually created a new subinterface between the Physical layer and the Data Link layer called the Reconciliation Sublayer (RS). The RS maps the 1s and 0s to the MII interface. The MII uses a nibble, which is defined as 4 bits. AUI used only 1 bit at a time. Data transfers across the MII at one nibble per clock cycle, which is 25MHz. 10Mbps uses a 2.5MHz clock.</PARA>
</SECTION>
<SECTION ID="2.2.2.4"><TITLE>Full-Duplex Ethernet and FastEthernet</TITLE>
<PARA>Full-duplex Ethernet can both transmit and receive simultaneously and uses point-to-point connections. It is typically referred to as collision free because it doesn't share bandwidth with any other devices. Frames sent by two nodes cannot collide because there are physically separate transmit and receive circuits between the nodes. </PARA>
<SECTION ID="2.2.2.4.1"><TITLE>Use Full-Duplex Ethernet in the Distribution Layer</TITLE>
<PARA>Because users typically use client/server applications using read/write asymmetrical traffic, the best performance for full-duplex would be in the distribution layer, not necessarily in the access layer. </PARA>
<PARA>Full-Duplex with Flow Control was created to avoid packets being dropped if the buffers on an interface fill up before all packets can be processed. However, some vendors might not interoperate, and the buffering might have to be handled by upper-layer protocols instead. </PARA>
<PARA>Auto-negotiation is a process that allows clients and switches to agree on a link capability. This is used to determine the link speed as well as the duplex being used. The auto-negotiation process uses priorities to set the link configuration. Obviously, if both a client and switch port can use 100Mbps, full-duplex connectivity, that would be the highest-priority ranking, whereas half-duplex, 10Mbps Ethernet is the lowest ranking. </PARA>
<PARA>You need to understand that the auto-negotiation protocols do not work that well and you would be better off to configure the switch and NICs to run in a dedicated mode instead of letting the clients and switches auto- negotiate. Later in this chapter, we'll show you how to configure your switches with both the speed and duplex options. </PARA>
</SECTION>
<SECTION ID="2.2.2.6"><TITLE>Distance</TITLE>
<PARA>FastEthernet does have some drawbacks. It uses the same singing techniques as 10Mbps Ethernet, so it has the same distance constraints. In addition, 10Mbps Ethernet can use up to four repeaters, whereas FastEthernet can use only one or two, depending on the type of repeater. Table 2.1 shows a comparison of FastEthernet technologies.</PARA>
<TABLE NUM="2.1" TABLEENTRYNUM="3">
<TABLETITLE>Comparison of FastEthernet Technologies</TABLETITLE>
<TABLEENTRY><PARA>Category 5 UTP wiring, category 6 and 7 is now available. Category 6 is sometimes referred to as cat 5 plus. Two-pair wiring. </PARA></TABLEENTRY>
<TABLEENTRY><PARA>100 meters </PARA></TABLEENTRY>
</TABLEROW>
<TABLEROW>
<TABLEENTRY><PARA>100BaseT4</PARA></TABLEENTRY>
<TABLEENTRY><PARA>Four-pair wiring, using UTP category 3, 4, or 5. </PARA></TABLEENTRY>
<TABLEENTRY><PARA>100 meters</PARA></TABLEENTRY>
</TABLEROW>
<TABLEROW>
<TABLEENTRY><PARA>100BaseFX</PARA></TABLEENTRY>
<TABLEENTRY><PARA>Multi-Mode Fiber (MMF) with 62.5-micron fiber-optic core with a 125-micron outer cladding (62.5/125).</PARA></TABLEENTRY>
<PARA>In the corporate market, <KEYTERM>Gigabit Ethernet</KEYTERM> is the new hot thing. What is so great about Gigabit is that it can use the same network that your 10 and 100Mbps Ethernet now use. You certainly do have to worry about distance constraints, but what a difference it can make in just a server farm alone!</PARA>
<PARA>Just think how nice it would be to have all your servers connected to Ethernet switches with Gigabit Ethernet and all your users using 100BaseT switched connections. Of course, all your switches would connect with Gigabit links as well. Add the hot xDSL to connect to the Internet and you have more bandwidth than you ever could have imagined just a few years ago. Will it be enough bandwidth a few years from now? Probably not. If you have the bandwidth, users will find a way to use it.</PARA>
<SECTION ID="2.2.3.1"><TITLE>Use Gigabit Ethernet in the Switch, Core, and Server Blocks</TITLE>
<PARA>Gigabit Ethernet can work in the switch block, the core block, and your server blocks:</PARA>
<RUNINBLOCK><RUNINHEAD>Switch block</RUNINHEAD>
<RUNINPARA>You can use Gigabit Ethernet between the access layer switches and the distribution layer switches. Gigabit is not typically connected to end users, but that can change quickly.</RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>Core block</RUNINHEAD>
<RUNINPARA>You can use Gigabit Ethernet to connect distribution layer switches in each building to the core switches.</RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>Server block</RUNINHEAD>
<RUNINPARA>By placing a Gigabit switch in the server block, you can effectively connect your high-performance servers to the network with gigabit speeds. However, remember that, unless the server is tremendously fast, you might not notice a difference in speeds from FastEthernet because the server processing can become the bottleneck. Time to throw out your Pentium 90 servers. </RUNINPARA></RUNINBLOCK>
<PARA>Gigabit Ethernet became an IEEE 802.3 standard in the summer of 1998. The standard was called 802.3z. Gigabit uses Ethernet framing the same way 10BaseT and FastEthernet does. This means that, not only is it fast, it can run on the same network as older Ethernet technology, which provides a nice migration plan. The goal of the IEEE 802.3z was to maintain compatibility to the 10Mb/s and 100Mb/s existing Ethernet network. They needed to provide a seamless operation to forward frames between segments running at different speeds. The committee kept the minimum and maximum frame lengths the same. However, they needed to change the CSMA/CD for half-duplex operation from its 512-bit times to help the distance that Gigabit Ethernet could run.</PARA>
<PARA>Will Gigabit ever run to the desktop? Maybe. People said that FastEthernet would never run to the desktop when it came out, but it's now common. If Gigabit is run to the desktop, however, it's hard to imagine what we'll need to run the backbone with. 1000BaseT to the rescue! Yes, 10 Gigabit Ethernet is just around the corner! </PARA>
</SECTION>
<SECTION ID="2.2.3.3"><TITLE>Comparing 10BaseT, FastEthernet, and Gigabit Ethernet</TITLE>
<PARA>There are some major differences between FastEthernet and Gigabit Ethernet. FastEthernet uses the Media Independent Interface (MII), and Gigabit uses the Gigabit Media Independent Interface (GMII). 10BaseT used the Attachment Unit Interface, or AUI. A new interface was designed to help FastEthernet scale to 100Mbps, and this interface was redesigned for Gigabit Ethernet. The GMII uses an 8-bit data path instead of the 4-bit path that FastEthernet MII uses. The clocking must operate at 125MHz to achieve the 1Gb/s data rate. </PARA>
</SECTION>
<SECTION ID="2.2.3.4"><TITLE>Time Slots</TITLE>
<PARA>Because Ethernet networks are sensitive to the round-trip-delay constraint of CSMA/CD, time slots are extremely important. Remember that in 10BaseT and 100BaseT, the time slots were 512-bit times. However, this is not feasible for Gigabit because the time slot would be only 20 meters in length. To make Gigabit useable on a network, the time slots were extended to 512 bytes (4096-bit times!). However, the operation of full-duplex Ethernet was not changed at all. Table 2.2 compares the new Gigabit Ethernet technologies.</PARA>
<TABLE NUM="2.2" TABLEENTRYNUM="3">
<TABLETITLE>Comparison of Gigabit Ethernet Technologies</TABLETITLE>
<TABLEENTRY><PARA>MMF using 62.5 and 50-micron core, uses a 780-nanometer laser</PARA></TABLEENTRY>
<TABLEENTRY><PARA>260 meters</PARA></TABLEENTRY>
</TABLEROW>
<TABLEROW>
<TABLEENTRY><PARA>1000BaseLX</PARA></TABLEENTRY>
<TABLEENTRY><PARA>Single-mode fiber that uses a 9-micron core, 1300- nanometer laser</PARA></TABLEENTRY>
<TABLEENTRY><PARA><NOBR>3 km</NOBR> up to <NOBR>10 km</NOBR></PARA></TABLEENTRY>
</TABLEROW>
</TABLEBODY>
</TABLE>
</SECTION>
</SECTION>
</SECTION>
<SECTION ID="2.3"><TITLE>Connecting and Logging In to a Switch</TITLE>
<PARA><DROPCAP>I</DROPCAP>n this section, you will learn about two different types of switches Cisco sells: the Catalyst 1900, which is IOS based, and the Catalyst 5000, which is set based. The Catalyst 1900 switch can now use a command-line interface (CLI) and the Cisco Internetworking Operating System (IOS) runs on the switch. This makes configuring the switch very similar to how you would configure a router. The 5000 series is still set based, which means you use the command <INLINECODE>set</INLINECODE> to configure the router. Throughout the rest of this course, we'll show you commands on both types of switches.</PARA>
<PARA>There are two types of operating systems that run on Cisco switches:</PARA>
<RUNINBLOCK><RUNINHEAD>IOS based</RUNINHEAD>
<RUNINPARA>You can configure the switch from a command-line interface (CLI) that is very similar to the one used on Cisco routers. Catalyst 1900, 2820, and 2900 switches can be used with an IOS-based CLI, although they can be set with a menu system as well. </RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>Set based</RUNINHEAD>
<RUNINPARA>Uses older, set-based CLI configuration commands. The Cisco switches that use the set-based CLI are the 2926 series, the 1948G, the 4000, the 5000, and the 6000 series.</RUNINPARA></RUNINBLOCK>
<PARA>It's time to be introduced to the 1900 and 5000 series of Catalyst switches. Why the 1900? Cisco uses it on the exams, of course, and it allows you to run a CLI with IOS-based commands on a less-expensive switch than you would need to use with the 5000 series. The 1900 switches are great for home offices or other small offices where you can get 10Mbps switched ports with 100Mbps uplinks at a decent price. It sure beats shared hubs! </PARA>
<SECTION ID="2.3.1" POS="1"><TITLE>Cabling the Switch Block Devices</TITLE>
<PARA>You can physically connect to a Cisco Catalyst switch by connecting either to the console port or an Ethernet port, just as you would with a router.</PARA>
<SECTION ID="2.3.1.1"><TITLE>Connecting to the Console Port</TITLE>
<PARA>The 1900 and 5000 series switches both have a console connector. However, the 5000 series switch has a console connector that uses only an RS-232-type connector, which will come with the switch when purchased. The 1900 switch, on the other hand, has a console port on the back, which is an RJ-45 port. Both console cables are rolled cables.</PARA>
<NOTE>1924 switches use a null-modem cable for the console port.</NOTE>
<PARA>After you connect to the console port, you need to start a terminal emulation program like Hyperterm in Windows. The settings are as follows:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>9600 BPS</PARA></LISTITEM>
<LISTITEM><PARA>8 data bits</PARA></LISTITEM>
<LISTITEM><PARA>No parity</PARA></LISTITEM>
<LISTITEM><PARA>1 stop bits</PARA></LISTITEM>
<LISTITEM><PARA>No flow control</PARA></LISTITEM>
</LIST>
<WARNING>Do not connect an Ethernet cable, ISDN, or live telephone line into the console port. These things can damage the electronics of the switch.</WARNING>
</SECTION>
<SECTION ID="2.3.1.2"><TITLE>Connecting to an Ethernet Port</TITLE>
<PARA>The Catalyst 1900/2800 series switches have fixed port types. They are not modular like the 5000 series switches. The 1900/2800 switches use only 10BaseT ports for workstations and 100BaseT or FX for uplinks. Each switch has either 12 (model 1912) or 24 (model 1924) 10BaseT switch ports with 2 FastEthernet uplinks. The 100BaseTX ports are referred to as ports A and B. We have connected servers into these ports and are able to run 100Mbps. Works great for a small network. To connect the ports to another switch as an uplink, you must use a crossover cable. It would be nice if there were a button for this function, but there isn't.</PARA>
<PARA>The Catalyst 5000 switches can run either 10 or 100Mbps on any port, depending on the type of cards you buy. The supervisor cards always take the first slot and have two 100BaseTX or FX ports for uplinks. All devices connected into either the 1900/2800 or 5000 series switches must be within 100 meters (330 feet) of the switch port. </PARA>
<NOTE>When connecting devices like workstations, servers, printers, and routers to the switch, you must use a straight-through cable. Use a crossover cable to connect between switches.</NOTE>
<PARA>When a device is connected to a port, the port status LED light comes on and stays on. If the light does not come on, the other end might be off or there might be a cable problem. Also, if a light comes on and off, an auto-speed and duplex problem is possible. We'll show you how to check that in the next section. </PARA>
<PARA>The 5000 series switch loads the software image from flash, then asks you to enter a password, even if there isn't one set. Press Enter, and then you will see a Console > prompt. At this point, you can enter enable mode and configure the switch using <INLINECODE>set</INLINECODE> commands:</PARA>
<CODESNIPPET><CODELINE>BOOTROM Version 5.1(2), Dated Apr 26 1999 10:41:04</CODELINE>
<PARA>When you connect to the 1900 console, the menu below appears. By pressing K, you can use the command-line interface, and M will allow you to configure the switch through a menu system. The I option allows you to configure the IP configuration of the switch (this can also be accomplished through the menu or CLI at any time). Once the IP configuration is set, the I selection no longer appears:</PARA>
<CODESNIPPET><CODELINE>1 user(s) now active on Management Console.</CODELINE>
<CODELINE> CLI session with the switch is open.</CODELINE>
<CODELINE> To end the CLI session, enter [Exit].</CODELINE>
<CODELINE></CODELINE>
<CODELINE>></CODELINE></CODESNIPPET>
</SECTION>
</SECTION>
<SECTION ID="2.3.2"><TITLE>Cisco IOS- and Set-Based Commands</TITLE>
<PARA>In this section, you'll learn how to configure the basics on both types of switches. Specifically, you'll learn how to do the following:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>Set the passwords</PARA></LISTITEM>
<LISTITEM><PARA>Set the hostname</PARA></LISTITEM>
<LISTITEM><PARA>Configure the IP address and subnet mask</PARA></LISTITEM>
<LISTITEM><PARA>Identify the interfaces</PARA></LISTITEM>
<LISTITEM><PARA>Set a description on the interfaces</PARA></LISTITEM>
<LISTITEM><PARA>Configure the port speed</PARA></LISTITEM>
<LISTITEM><PARA>Define the port duplex</PARA></LISTITEM>
<LISTITEM><PARA>Verify the configuration</PARA></LISTITEM>
</LIST>
<SECTION ID="2.3.2.1"><TITLE>Setting the Passwords</TITLE>
<PARA>The first thing you should do is configure the passwords. You don't want unauthorized users connecting to the switch. You can set both the usermode and privileged mode passwords, just as you can with a router. However, you use different commands.</PARA>
<PARA>As with any Cisco router, the login (usermode) password can be used to verify authorization of the switch, including telnet and the console port. The enable password is used to allow access to the switch so the configuration can be viewed or changed. </PARA>
<NOTE>The passwords cannot be less than four characters or more than eight. They are not case sensitive.</NOTE>
<SECTION ID="2.3.2.1.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>To configure the two passwords on a 5000 series switch, use the command <INLINECODE>set password</INLINECODE> for the usermode password and the command <INLINECODE>set enablepass</INLINECODE> for the enable password:</PARA>
<CODESNIPPET><CODELINE>1997 Mar 21 06:31:54 %SYS-5-MOD_OK:Module 1 is online</CODELINE>
<CODELINE>1997 Mar 21 06:31:54 %SYS-5-MOD_OK:Module 2 is online</CODELINE>
<PARA>When you see the "Enter old password" prompt, you can leave it blank and press Enter if you don't have a password set. The output for the "Enter new password" prompt doesn't show on the console screen. If you want to clear the usermode (login) password, type in the old password and then just press Enter when you're asked for a new password. </PARA>
<PARA>To set the enable password, use the command <INLINECODE>set enablepass</INLINECODE>, then press Enter: </PARA>
<PARACONTINUED>You can type <EMPHASIS FORMAT="bold">exit</EMPHASIS> at this point to log out of the switch completely, which will allow you to test your new passwords. </PARACONTINUED>
<PARA>Even though the 1900 switch is a CLI running an IOS, the commands for the usermode and enable mode passwords are different than they are for a router. You use the command <INLINECODE>enable password</INLINECODE>, which is the same, but you choose different access levels, which is optional on a Cisco router but not on the 1900 switch. The enable secret password can be set as well, and it supercedes the enable password level 15. The telnet password is set by setting either the enable password level 15 or the enable secret password. </PARA>
<PARA>Press K to enter CLI mode, and then enter enable mode and global configuration mode by using the <INLINECODE>config t</INLINECODE> command: </PARA>
<CODESNIPPET><CODELINE>1 user(s) now active on Management Console.</CODELINE>
<PARA>Notice that the program prompted for a usermode password, which was the level 1 password entered. The enable password was the enable secret password set, which superceded the enable password level 15.</PARA>
</SECTION>
</SECTION>
<SECTION ID="2.3.2.2"><TITLE>Setting the Hostname</TITLE>
<PARA>The hostname on a switch, as well as on a router, is only locally significant. This means that it doesn't have any function on the network or for name resolution whatsoever. However, it is helpful to set a hostname on a switch so you can identify the switch when connecting to it. A good rule of thumb is to name the switch after the location it is serving. </PARA>
<SECTION ID="2.3.2.2.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>To set the hostname on a 5000 series switch, use the <INLINECODE>set prompt</INLINECODE> command: </PARA>
<CODESNIPPET><CODELINE>Cisco Systems Console Thu Mar 21 1997, 06:31:54</CODELINE>
<PARA>Because the location is his office, Todd5000 works for Todd. Notice that the first command used did not include a > prompt. We like to see that prompt, but you have to choose it. On a router, you can change the prompt, but the default is always a > prompt. </PARA>
<PARA>The 1900 switch command to set the hostname is exactly as it is with any router. You use the <INLINECODE>hostname</INLINECODE> command (remember, it is one word):</PARA>
<CODESNIPPET><CODELINE>1 user(s) now active on Management Console.</CODELINE>
<SECTION ID="2.3.2.3"><TITLE>Setting the IP Information</TITLE>
<PARA>You do not have to set any IP configuration on the switch to make it work. You can just plug in devices and they should start working, as they do on a hub. IP address information is set so that you can either manage the switch via Telnet or other management software or configure the switch with different VLANs and other network functions.</PARA>
<SECTION ID="2.3.2.3.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>To set the IP address information on a 5000 series switch, configure the supervisor engine that is plugged into slot one of every switch. This is called the <KEYTERM>in-band</KEYTERM> logical interface. Use the command <INLINECODE>set interface sc0</INLINECODE>: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set int sc0 172.16.10.17 255.255.255.0</EMPHASIS></CODELINE>
<CODELINE>Interface sc0 IP address and netmask set.</CODELINE></CODESNIPPET>
<PARA>By default, the switch is configured for VLAN 1, which can be seen by using the <INLINECODE>show interface</INLINECODE> command. Notice also that the broadcast address for the subnet shows up and that you can change that by entering it with the <INLINECODE>set int sc0</INLINECODE> command (but we can think of only one reason you would want to change that-to mess with the people in your MIS department):</PARA>
<PARA>If you wanted to have the switch in a different VLAN, instead of the default VLAN 1, you can use the <INLINECODE>set int sc0</INLINECODE> command: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set int sc0 2</EMPHASIS></CODELINE>
<PARA>Cisco recommends that you use the VLAN 1 for management of the switch device and then create other VLANs for users. In other words, they don't recommend what we just showed you.</PARA>
<PARA>To set the IP configuration on a 1900 switch, use the command <INLINECODE>ip address</INLINECODE>. By typing the command <INLINECODE>show ip</INLINECODE>, you can see the configuration (by default, nothing is set): </PARA>
<PARA>It is important to understand how to access switch ports. The 5000 series uses the <INLINECODE>slot/port</INLINECODE> command. The 1900 series of switches uses the <INLINECODE>type slot/port</INLINECODE> command. </PARA>
<SECTION ID="2.3.2.4.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>You can use the <INLINECODE>show</INLINECODE> command to view port statistics on a 5000 switch. Notice that, by default, the duplex and speed of the port are both set to auto. Also, typically the ports on a 2900, 4000, 5000, and 6000 series switch may be enabled, but it might be necessary to configure the ports so that they can be enabled with the <INLINECODE>set port enable</INLINECODE> command. You can turn off any port with the <INLINECODE>set port disable</INLINECODE> command: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">show port ?</EMPHASIS></CODELINE>
<CODELINE>Usage: show port</CODELINE>
<CODELINE> show port <mod_num></CODELINE>
<CODELINE> show port <mod_num/port_num></CODELINE>
<CODELINE>Todd5000> (enable) show port 2/1</CODELINE>
<CODELINE>Port Name Status Vlan Level Duplex Speed Type</CODELINE>
<PARA>The 1900 switch takes the <INLINECODE>type slot/port</INLINECODE> command with either the <INLINECODE>interface</INLINECODE> command or the <INLINECODE>show</INLINECODE> command. The <INLINECODE>interface</INLINECODE> command allows you to set interface-specific configurations. The 1900 switch has only one slot, zero (0): </PARA>
<PARA>You can switch between interfaces by using the <INLINECODE>int e 0/#</INLINECODE> command. Notice that we demonstrate below commands with spaces or without-it makes no difference. </PARA>
<PARA>To configure the two FastEthernet ports, the command is <INLINECODE>interface fastethernet 0\#</INLINECODE>. You cannot go to the FastEthernet ports from the 10BaseT ports without typing <EMPHASIS FORMAT="bold">exit</EMPHASIS> to go back one level: </PARA>
<CODESNIPPET><CODELINE>Todd1900EN(config-if)#<EMPHASIS FORMAT="bold">int e 0/2</EMPHASIS></CODELINE>
<PARA>You can set a description on an interface, which will allow you to administratively set a name for each interface. As with the hostname, the descriptions are only locally significant. </PARA>
<SECTION ID="2.3.2.5.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>To set a description with the 5000 switch, use the <INLINECODE>set port name slot/port</INLINECODE> command. Spaces are allowed. You can set a name up to 21 characters long: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set port name 2/1 Sales Printer</EMPHASIS></CODELINE>
<CODELINE>Port 2/1 name set.</CODELINE>
<CODELINE>Todd5000> (enable) sh port 2/1</CODELINE>
<CODELINE>Port Name Status Vlan Level Duplex Speed Type</CODELINE>
<PARA>For the 1900 series switch, use the <INLINECODE>description</INLINECODE> command. You cannot use spaces with the <INLINECODE>description</INLINECODE> command, but you can use underlining if you need to: </PARA>
<PARA>You can view the descriptions with either the <INLINECODE>show interface</INLINECODE> command or the <INLINECODE>show running-config</INLINECODE> command: </PARA>
<CODESNIPPET><CODELINE>Todd1900EN#<EMPHASIS FORMAT="bold">sh int e0/1</EMPHASIS></CODELINE>
<CODELINE>Ethernet 0/1 is Suspended-no-linkbeat</CODELINE>
<CODELINE>Hardware is Built-in 10Base-T</CODELINE>
<SECTION ID="2.3.2.6"><TITLE>Configuring the Port Speed and Duplex</TITLE>
<PARA>By default, all 10/100 ports on the 5000 series switch are set to auto-detect the speed and duplex of the port. However, the 1900 switch has only 12 or 24 10BaseT ports, which cannot be changed. It comes with one or two FastEthernet ports, which allows you to change the duplex only. The 2820 series has 24 10BaseT ports and 2 modular slots for FastEthernet. </PARA>
<SECTION ID="2.3.2.6.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>Because the ports on a 10/100 card are auto-detect, you don't have to necessarily set the speed and duplex. However, there are situations where the auto-detect does not work correctly, and by setting the speed and duplex, you can stabilize the link: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set port speed 2/1 ?</EMPHASIS></CODELINE>
<CODELINE>Usage: set port speed <mod_num/port_num> <4|10|16|100|auto></CODELINE>
<CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set port speed 2/1 100</EMPHASIS></CODELINE>
<CODELINE>Port(s) 2/1 speed set to 100Mbps.</CODELINE></CODESNIPPET>
<PARA>If you set the port speed to auto, both the speed and duplex are set to auto-negotiate the link. You can't set the duplex without first setting the speed: </PARA>
<CODESNIPPET><CODELINE>Todd5000> (enable) <EMPHASIS FORMAT="bold">set port duplex 2/1 ?</EMPHASIS></CODELINE>
<CODELINE>Usage: set port duplex <mod_num/port_num> <full|half></CODELINE>
<CODELINE>Todd5000> (enable) set port duplex 2/1 full</CODELINE>
<CODELINE>Port(s) 2/1 set to full-duplex.</CODELINE>
<PARA>You can set only the duplex on the 1900 switch because the ports are all fixed speeds. Use the <INLINECODE>duplex</INLINECODE> command in interface configuration: </PARA>
<SECTION ID="2.3.2.7"><TITLE>Verifying IP Connectivity</TITLE>
<PARA>It is important to test the switch IP configuration. You can, of course, use the Ping program, as well as Telnet. The 5000 series also allows you to use the traceroute command. </PARA>
<SECTION ID="2.3.2.7.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>Use the IP utilities Ping, Telnet, and traceroute to test the switch in the network: </PARA>
<PARA>You can use the Ping program, and you can telnet into the 1900 switch. However, you cannot telnet from the 1900 switch or use traceroute: </PARA>
<CODELINE>Sending 5, 100-byte ICMP Echos to 172.16.10.10, time out is 2 seconds:</CODELINE>
<CODELINE>!!!!!</CODELINE>
<CODELINE>Success rate is 100 percent (5/5), round-trip min/avg/max 0/2/10/ ms</CODELINE>
<CODELINE>Todd1900EN#telnet</CODELINE>
<CODELINE> ^</CODELINE>
<CODELINE>% Invalid input detected at '^' marker.</CODELINE></CODESNIPPET>
</SECTION>
</SECTION>
<SECTION ID="2.3.2.8"><TITLE>Erasing the Switch Configuration</TITLE>
<PARA>The switches automatically copy their configuration to NVRAM. You can delete the configurations if you want to start over. </PARA>
<SECTION ID="2.3.2.8.1"><TITLE>5000 Series Set-Based Switch</TITLE>
<PARA>To delete the configurations stored in non-volatile RAM (NVRAM) on the 5000 series switch, use the <INLINECODE>clear config all</INLINECODE> command. The <INLINECODE>erase all</INLINECODE> command will delete the contents of flash without warning! Be careful. Here is the code: </PARA>
<PARACONTINUED>Notice that when you type <INLINECODEUSERINPUT>erase all</INLINECODEUSERINPUT> and press Enter, it just starts erasing the flash and you can't break out of it. By doing a <INLINECODE>show flash</INLINECODE> command, you can see that the contents of flash are now empty. You might not want to try this on your production switches. You can use the <INLINECODE>copy tftp flash</INLINECODE> command to reload the software. </PARACONTINUED>
<PARA>To delete the contents of NVRAM on a 1900 switch, use the <INLINECODE>delete NVRAM</INLINECODE> command. VLAN Trunk Protocol configuration is not deleted by using <INLINECODE>delete VRAM</INLINECODE> because it has its own NVRAM. You need to use the command <INLINECODE>delete vtp</INLINECODE> to clear the VTP configuration: </PARA>
<CODELINE> vtp Reset VTP configuration to defaults</CODELINE>
<CODELINE>Todd1900EN#delete nvram</CODELINE>
<CODELINE>This command resets the switch with factory defaults. All system parameters will revert to their default factory settings. All static and dynamic addresses will be removed.</CODELINE>
<CODELINE>Reset system with factory defaults, [Y]es or [N]o? Yes</CODELINE></CODESNIPPET>
</SECTION>
</SECTION>
</SECTION>
</SECTION>
<SECTION ID="2.4"><TITLE>Summary</TITLE>
<PARA><DROPCAP>T</DROPCAP>his chapter covered the different types of Ethernet you can use in an internetwork as well as the distance each type of Ethernet media can run. It's important to remember what you learned here. </PARA>
<PARA>Remember that the distance that 10BaseT can run and be within specification is 100 meters (330 feet). The 100 meters includes the following:</PARA>
<LIST MARK="bullet">
<LISTITEM><PARA>Five meters from the switch to the patch panel</PARA></LISTITEM>
<LISTITEM><PARA>Ninety meters from the patch panel to the office punch-down block</PARA></LISTITEM>
<LISTITEM><PARA>Five meters from the punch-down block to the desktop connection</PARA></LISTITEM>
</LIST>
<PARA>For FastEthernet, the specifications for each type are as follows:</PARA>
<RUNINBLOCK><RUNINHEAD>100BaseTX</RUNINHEAD>
<RUNINPARA>Category 5 UTP wiring; category 6 and 7 is now available. Category 6 is sometimes referred to as cat 5 plus. Two-pair wiring. 100 meters. </RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>100BaseT4</RUNINHEAD>
<RUNINPARA>Four-pair wiring, using UTP category 3, 4, or 5. 100 meters.</RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>100BaseFX</RUNINHEAD>
<RUNINPARA>Multi-Mode Fiber (MMF) with 62.5-micron fiber-optic core with a 125-micron outer cladding (62.5/125). 400 meters. </RUNINPARA></RUNINBLOCK>
<PARA>For Gigabit Ethernet, the specifications for each type are as follows:</PARA>
<RUNINPARA>MMF using 62.5 and 50-micron core, uses a 780- nanometer laser, up to 260 meters.</RUNINPARA></RUNINBLOCK>
<RUNINBLOCK><RUNINHEAD>1000BaseLX</RUNINHEAD>
<RUNINPARA>Single-mode fiber that uses a 9-micron core, 1300- nanometer laser. From 3 km up to 10 km. </RUNINPARA></RUNINBLOCK>
<PARA>We showed you how to configure both a set-based switch and a command-line interface (CLI) switch. And we showed you how to set hostnames and passwords. Finally, you learned how to configure an IP address on each switch and how to verify the configuration. </PARA>
<TABULARENTRY>Shows the current configuration of the switch</TABULARENTRY>
</TABULARROW>
<TABULARROW>
<TABULARENTRY>Ctrl+Shift+6, then x</TABULARENTRY>
<TABULARENTRY>Used as an escape sequence</TABULARENTRY>
</TABULARROW>
</TABULARBODY>
</TABULARDATA>
</SECTION>
</SECTION>
<TESTSECTION ID="2.5"><TITLE>Written Lab</TITLE>
<!-- <TESTDATA>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>100BaseFX is a point-to-point Ethernet topology that can run up to ___ meters.</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>1000BaseSX uses a 780-meter laser that can run a distance of ___ meters.</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>100BaseT can run a total distance of ___ meters.</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What command will set port 3 on card 2 of a 5000 series switch to full duplex?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What command will allow you to view the speed and duplex of port 6 on card 3 of a 5000 switch?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What command will show you the IP address of a 1900 switch?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>How do you set the IP address on a 5000 series switch to 172.16.10.17 255.255.255.0?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What command sets the enable password on a 5000 series switch?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What three IP commands can be used to test network connectivity of a device?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
<TESTBLOCK><QUESTIONBLOCK><QUESTION>What type of Ethernet topology is suggested at the core layer?</QUESTION></QUESTIONBLOCK></TESTBLOCK>
</TESTDATA> -->
<SLUG NONUM="w1"/>
</TESTSECTION>
<SECTION ID="2.6"><TITLE>Hands-On Lab</TITLE>
<PARA>This lab will provide step-by-step instructions for configuring both access layer and distribution layer switches. You'll use a 1900 switch for the access layer and a 5000 series switch for the distribution layer. Figure 2.1 will provide the network diagram that will be configured in this lab. </PARA>
<SLUG NUM="2.1">Figure 2.1: Access layer to distribution layer configuration [f0201.eps]</SLUG>
<LIST MARK="number">
<LISTITEM><PARA>Configure the access layer switch by going to the console and pressing K to enter the CLI.</PARA></LISTITEM>
<LISTITEM><PARA>Assign the usermode password:</PARA>
