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The Catalyst 8500 campus switch router is a modular Layer 2 and Layer 3 switch router that provides wire speed Ethernet routing and switching services. The system can be deployed as a high-speed switch router for campus or enterprise backbones.
The key features of the Catalyst 8500 campus switch router include wirespeed Layer 3 IP, IP multicast, and IPX routing and forwarding across Ethernet, Fast EtherChannel (FEC), and Gigabit EtherChannel (GEC) interfaces. The switch router supports virtual LANs between switches via the Inter-Switch Link (ISL) trunking protocol and the 802.1q standard. The switch router also provides high quality of service (QoS) capabilities, including support for four queues per port and flow classification based on IP precedence bits.
The Catalyst 8500 campus switch router is available in two models: the Catalyst 8510 campus switch router and the Catalyst 8540 campus switch router.
The Catalyst 8510 campus switch router system has a five-slot chassis that contains one or more power supplies, a switch route processor (SRP), and line modules. (See Figure 1-2.)
The ability to use Catalyst 8510 Ethernet line modules in a Catalyst 5500 chassis provides an easy migration to wirespeed Layer 3 networking. The Catalyst 5500 switch provides full integration of the Catalyst 8510 line modules by using the passive backplane fabric in the Catalyst 5500 lower five slots (9 through 12). The Catalyst 8510 SRP resides in slot 13 in the Catalyst 5500 chassis. For information on configuring the SRP, see the chapter "Configuring the Switch Route Processor for the Catalyst 8510 and Using Flash Memory Cards."
The Catalyst 8510 campus switch router supports the interface types listed in Table 1-1.
| Interface Types | Ports per Slot | Maximum Density |
|---|---|---|
10/100 Mbps Fast Ethernet - UTP | 8 | 32 |
100 Mbps Fast Ethernet - Multimode Fiber | 8 | 32 |
1 Gbps Gigabit Ethernet uplink | 1 | 4 |
The Catalyst 8540 campus switch router system has a 13-slot chassis that contains one or more power supplies, a route processor, switch modules, and line modules. (See Figure 1-3.)
The Catalyst 8540 campus switch router supports the interface types listed in Table 1-2.
| Interface Types | Ports per Slot | Maximum Density |
|---|---|---|
10/100 Mbps Fast Ethernet - UTP | 16 | 128 |
100 Mbps Fast Ethernet - Multimode Fiber | 16 | 128 |
1 Gbps Gigabit Ethernet uplink | 2 | 16 |
The Catalyst 8500 series of campus switch routers provides a complete and resilient backbone switch that offers a complete suite of sophisticated features. This system offers several key components of the enterprise campus network architecture, delivering high-speed performance and quality of service within the network backbone. By incorporating the Cisco IOS technology, the Catalyst 8500 provides seamless integration with the Catalyst 5000 series (including the Route Switch Module and NetFlow feature card), as well as the Cisco 7500 class of routers.
The Catalyst 8500 supports a 1-gigabit line module that offers gigabit Ethernet transmission over fiber connections. The gigabit line module offers a GBIC (gigabit interface converter) interface, which you can interchange with other GBIC cartridges.
The Catalyst 8510 supports a single-port 1-gigabit line module that provides a single GBIC interface. You can install up to four gigabit line modules in the Catalyst 8510 chassis.
The features of the Catalyst 8510 gigabit Ethernet line module are as follows:
The features of the Catalyst 8540 gigabit Ethernet line module are as follows:
For configuration information, see the section "Configuring the Gigabit Ethernet Interface" in the chapter "Configuring the Catalyst 8500 Software."
For configuration information, see the section "Configuring the EtherChannel" in the chapter "Configuring the Catalyst 8500 Software."
For configuration information, see the section "Configuring the Fast EtherChannel" in the chapter "Configuring the Catalyst 8500 Software."
Quality of Service (QoS) comprises several technologies, such as the Resource Reservation Protocol (RSVP) and Weighted Fair Queuing (WFQ), which help control bandwidth, network delay, jitter, and packet loss in networks that become congested. In the switch router, QoS-based forwarding sorts traffic into a small number of classes and marks the packets accordingly. The QoS identifier provides specific treatment to traffic in different classes, so that different quality of service is provided to each class.
On any Catalyst 8500 system in the network, the frame and packet scheduling and discarding policies are determined by the class to which the frames and packets belong. For example, the overall service given to frames and packets in the premium class will be better than that given to the standard class; the premium class is expected to experience lower loss rate or delay.
The switch router supports QoS-based forwarding for IP traffic only (for the initial release). The implementation of QoS forwarding is based on local administrative policy and IP precedence. The mapping between the IP precedence field and the QoS field determines the delay priority of the packet. Refer to the chapter "Catalyst 8500 Quality of Service Feature Summary" for detailed information about QoS mechanisms on the Catalyst 8500 and the QoS configuration commands with which you to fine tune your QoS configuration.
The Catalyst 8500 chassis features hot-swappable, redundant power supply modules, as well as hot-swappable Ethernet line modules. The redundancy of Cisco IOS software provides key network features, such as Hot Standby Router Protocol (HSRP), routing protocol convergence with Routing Information Protocol (RIP), Open Shortest Path First (OSPF), or Enhanced Interior Gateway Routing Protocol (EIGRP), Fast EtherChannel, and load sharing across equal cost Layer 3 paths and spanning tree (for Layer 2 based networks).
The Catalyst 8500 supports port-based snooping. With port-based snooping, traffic is transparently mirrored to a snoop destination port where an external traffic analyzer can be attached. Port-based snooping monitors the following:
| Layer 1 Features |
|---|
100BaseFX full duplex |
10/100BaseTX half duplex and full duplex with port speed detection (autonegotiation) |
1000BaseSX and LX full duplex |
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| Layer 2 Bridging Features |
Layer 2 transparent bridging |
Layer 2 MAC learning, aging, and switching by hardware |
Spanning-Tree Protocol (IEEE 802.1d, DEC) support per bridge group |
Support for a maximum of 64 active bridge groups |
Integrated Routing and Bridging (IRB) mode support |
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| Virtual LAN (VLAN) Features |
Inter-Switch Link (ISL)-based VLAN trunking support |
802.1q-based VLAN trunking support` |
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The following sections describe the notable Layer 2 features supported by the Catalyst 8500 campus switch router.
A virtual LAN (VLAN) facilitates the configuration of switches and routers according to logical rather than physical topologies. Using VLANs, a network administrator can combine any collection of LAN segments within an internetwork into an autonomous user group, which appears as a single LAN. VLANs logically segment the network into different broadcast domains so that packets are switched only between ports within the VLAN. Typically, a VLAN corresponds to a particular subnet, although not necessarily.
The Catalyst 8500 supports up to 255 VLANs per system. Because routing will take place, each VLAN is assumed to terminate at the Catalyst 8500. This might not necessarily be the case, so the switch router also supports integrated routing and bridging (IRB).
Configuring VLANs for the Catalyst 8500 is similar to VLAN configuration for other Cisco routers. You define a subinterface at the interface and then define a bridge group. Finally, map a VLAN to the subinterface. For details, see the section "Specifying Virtual LANs" in the chapter "Configuring the Catalyst 8500 Software."
To support a VLAN between switches, the Catalyst 8500 identifies frames from end stations as belonging to a particular VLAN. The Catalyst 8500 supports VLAN encapsulation via the 802.1q standard or Cisco's Inter-Switch Link (ISL) trunking protocol.
ISL and 802.1q encapsulation use a scheme known as packet tagging. Packet tagging allows the Catalyst 8500 series (as well as the Catalyst 3000 and 5000 series) to multiplex VLANs across a single physical link, maintaining strict adherence to the individual VLAN domains.
The frame is a standard Ethernet or IEEE 802.3 frame, encapsulated and tagged with a VLAN ID. Because it is a standard frame, repeater hubs and transparent bridges forward it as they would any other frame. Any 10/100 Mbps Ethernet link can support these encapsulation methods. The link can run at either half duplex or full duplex.
Each device configured for CDP sends periodic messages to a multicast address. Each device advertises at least one address at which it can receive Simple Network Management Protocol (SNMP) messages.
Layer 3 Routing, Switching, and Forwarding Features |
IP, IPX, and IP multicast switching between Ethernet ports |
CMF (Constrained Multicast Flooding) |
Support for up to 128 IP multicast groups |
QoS-based forwarding based on IP precedence queuing |
Load balancing among equal cost paths based on source and destination IP and IPX addresses |
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| Supported Routing Protocols |
Classless interdomain routing (CIDR) |
DVMRP (Distance Vector Multicast Routing Protocol) tunneling |
EIGRP (Enhanced Interior Gateway Routing Protocol) |
IGRP (Interior Gateway Routing Protocol) |
IPX (Internet Packet Exchange) RIP and EIGRP |
OSPF (Open Shortest Path First) |
PIM (Protocol Independent Multicast): Sparse and Dense modes |
RIP (Routing Information Protocol) and RIP II |
Route filtering |
Secondary addressing |
Static routes |
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| Fast EtherChannel (FEC) Features |
Bundling of up to 4 Fast Ethernet ports |
Load sharing based on source and destination IP addresses of unicast packets |
Load sharing for bridge traffic based on MAC address |
Inter-Switch Link (ISL) support on the Fast EtherChannel |
802.1q support on the Fast EtherChannel |
Support for up to 64 active FEC and GEC port channels in one system |
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| Gigabit EtherChannel (GEC) Features |
Bundling of up to 4 Gigabit Ethernet ports |
Load sharing based on source and destination IP addresses of unicast packets |
Load sharing for bridge traffic based on MAC address |
Inter-Switch Link (ISL) support on the Gigabit EtherChannel |
802.1q support on the Gigabit EtherChannel |
Support for up to 64 active FEC and GEC port channels in one system |
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| Additional Protocols and Features Supported |
BOOTP (Bootstrap Protocol) |
CGMP (Cisco Group Management Protocol) server support |
CDP (Cisco Discovery Protocol) support on Ethernet ports |
DHCP (Dynamic Host Configuration Protocol) Relay |
HSRP (Hot Standby Routing Protocol) over 10/100 Ethernet, Gigabit Ethernet, FEC, GEC, and BVI (Bridge Group Virtual Interface) |
ICMP (Internet Control Message Protocol) |
IGMP (Internet Group Management Protocol) |
IPX SAP (Internet Packet Exchange Service Advertisement Protocol) and SAP filtering |
IRB (Integrated Routing and Bridging) routing mode support |
SNMP (Simple Network Management Protocol) |
UDP (User Datagram Protocol) Turbo Flooding |
The following sections describe the notable Layer 3 features supported by the Catalyst 8500.
The Hot Standby Router Protocol (HSRP) provides high network availability by routing IP traffic from hosts on Ethernet networks without relying on the availability of any single router. This feature is particularly useful for hosts that do not support a router discovery protocol (such as the Intermediate System-to-Intermediate System Interdomain Routing Protocol) and do not have the functionality to switch to a new router when their selected router reloads or loses power.
Devices that are running the HSRP detect a failure by sending and receiving multicast User Datagram Protocol (UDP) "hello" packets. When HSRP detects that the designated active router has failed, the selected backup router assumes control of the HSRP group's MAC and IP addresses. (You can also select a new standby router at that time.)
The chosen MAC address and IP addresses are unique and will not conflict with any others on the same network segment. The MAC address is selected from a pool of Cisco MAC addresses. Configure the last byte of the MAC address by configuring the HSRP group number. You also configure the unique virtual IP address. The IP address must be specified on a single router within the same group. When the HSRP is running, it selects an active router and instructs its device layer to listen on an additional (dummy) MAC address.
The Catalyst 8500 supports HSRP over 10/100 Ethernet, Gigabit Ethernet, FEC, GEC, and BVI (Bridge Group Virtual Interface).
The Catalyst 8500 campus switch router provides a comprehensive suite of routing protocols based on the Cisco IOS software. The Catalyst 8500 supports RIP and RIP-2, OSPF, IGRP and EIGRP routing for IP networks. For IPX networks, the Catalyst 8500 supports IPX RIP and EIGRP. Many of the Cisco IOS routing protocol features, such as route redistribution and load balancing over equal cost paths (for OSPF and EIGRP) are supported. Configuration of these routing protocols is identical to the configuration methods currently employed on all of the Cisco router products.
CEF manages route distribution and forwarding by distributing routing information from the route processor (RP) to the individual Ethernet line modules. This technology, used within the Internet, provides scalability in large campus core networks. CEF provides Layer 3 forwarding based on a topology map of the entire network, resulting in high-speed routing table lookups and forwarding.
One of the key benefits of CEF in the Catalyst 8500 is its routing convergence. Since the forwarding information base (FIB) is distributed to all line modules, whenever a route goes away or is added, the FIB updates that information and provides it to the line modules. Thus, RP interrupts are minimized. The line modules receive the new topology very quickly and reconverge around a failed link based on the routing protocol being used.
The implementation of load balancing on the Catalyst 8500 employs a source + destination-based load balancing scheme, which is an enhanced version of the Cisco IOS software per-destination load balancing method. Essentially, this method takes certain bits from the source and destination IP addresses and maps this addressing information into a path. There are two benefits of using this method:
This release of the Catalyst 8500 campus switch router supports load balancing for two equal-cost paths. The system uses the destination and source address pair to perform load balancing. The switch router does not support per-packet load balancing.
Specifically, local or unroutable traffic is bridged among the bridged interfaces in the same bridge group, while routable traffic is routed to other routed interfaces or bridge groups.
The Catalyst 8500 supports IRB for IP and IPX only.
For configuration instructions, see the section "Configuring Integrated Routing and Bridging" in the chapter "Configuring the Catalyst 8500 Software."
Some examples of when to use IRB follow:
The Catalyst 8500 campus switch router supports User Datagram Protocol (UDP) turbo flooding. In IP internetworks, most broadcasts are UDP broadcasts. A directed broadcast is sent to a specific network or a series of networks. A flooded broadcast is a sent to every network.
Cisco's UDP turbo flooding feature uses the spanning tree algorithm to forward broadcasts in a controlled manner. When a Catalyst 8500 is configured for UDP broadcast flooding, Ethernet broadcasts are flooded out to all of the Fast Ethernet and gigabit Ethernet interfaces in a configured bridge group.
Bridging is enabled on each router interface for the sole purpose of building the spanning tree. The spanning tree prevents loops by stopping a broadcast from being forwarded out an interface on which the broadcast was received. The spanning tree also prevents packet duplication by placing certain interfaces in the blocked state (so that no packets are forwarded) and other interfaces in the forwarding state (so that packets that need to be forwarded are forwarded).
To enable UDP turbo flooding, the Catalyst 8500 campus switch router must be running software that supports transparent bridging and bridging must be configured on each interface that is to participate in the flooding. If bridging is not configured for an interface, the interface will receive broadcasts, but the switch router will not forward those broadcasts and will not use that interface as a destination for sending broadcasts received on a different interface.
UDP turbo flooding on the Catalyst 8500 platform is implemented using wirespeed switching technology.
The command interpreter is called the EXEC. You must log into the switch router or switch before you can enter an EXEC command. For security purposes, Cisco IOS software provides two levels of access to commands: user and privileged. The user mode is called user EXEC mode. The privileged mode is called privileged EXEC mode and requires a password.
Table 1-3 describes some of the most commonly used modes, how to enter the modes, and the resulting prompts. The prompt helps you identify which mode you are in and, therefore, which commands are available to you.
| Command Mode | Usage | How to Enter the Mode | Prompt Display |
|---|---|---|---|
User EXEC | Log in. | | |
Privileged EXEC | From the user EXEC mode, enter the enable command. | | |
Global configuration | From the privileged EXEC mode, enter the configure terminal command. | | |
Interface configuration | From global configuration mode, enter the interface type number command. For example, enter interface fa0/0/1 | | |
Console configuration | From global configuration mode, enter the line console 0 command. | |
When you type exit, the switch router backs out one level. In general, typing exit from one of the specific configuration modes returns you to global configuration mode. To exit configuration mode completely and return to privileged EXEC mode, press Ctrl-Z.
You can also abbreviate commands and keywords by entering just enough characters to make the command unique from other commands. For example, you can abbreviate the show command to sh.
In any command mode, you can get a list of available commands by entering a question mark (?).
Router> ?
To obtain a list of commands that begin with a particular character sequence, type in those characters followed immediately by the question mark ( ? ). Do not include a space. This form of help is called word help, because it completes a word for you.
Router# co?
configure connect copy
To list keywords or arguments, enter a question mark in place of a keyword or argument. Include a space before the question mark. This form of help is called command syntax help, because it reminds you which keywords or arguments are applicable based on the command, keywords, and arguments you have already entered.
Router# configure ?
memory Configure from NV memory
network Configure from a TFTP network host
terminal Configure from the terminal
To redisplay a command you previously entered, press the up-arrow key. You can continue to press the up-arrow to see more previously issued commands.
 | TimeSaver Each command mode restricts you to a subset of commands. If you are having trouble entering a command, check the prompt, and enter the question mark ( ? ) for a list of available commands. You might be in the wrong command mode or using incorrect syntax. |
You can press Ctrl-Z in any mode to immediately return to privileged EXEC (enable) mode (for example, 8500#), instead of entering exit, which returns you to the previous mode.
Posted: Thu Dec 30 11:45:21 PST 1999
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