RMON provides support for the following groups of Token Ring extensions:

∙MAC−Layer Statistics Group—A collection of statistics from the MAC sublayer of the Data Link layer, kept for each Token Ring interface. This group collects information such as the total number of MAC layer packets received and the number of times the port entered a beaconing error state.

∙Promiscuous Statistics Group—A collection of promiscuous statistics kept for non−MAC packets on each Token Ring interface. This group collects information such as the total number of good non−MAC frames received that were directed to a Logical Link Control (LLC) broadcast address.

∙Ring Station Group—A collection of statistics and status information associated with each Token Ring station on the local ring. This group also provides status information for each ring being monitored.

∙Ring Station Order Group—A list of the order of stations on the monitored Token Ring network’s rings.

To see a list of available commands, use the ? command. Table 2.1 provides a list of the ROM command−line interface commands and a brief description of each.

Table 2.1: ROM command−line interface commands.

Connecting to the Console Port

To initially configure a switch, you must make a connection to the console port and enter instructions to the switch from this port. The console comes preconfigured on a Cisco device and ready to use. You can access the console port in a number of ways, as shown in Figure 2.2.

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Figure 2.2: The different types of console ports on the switches.

The console port must be accessed through a PC or another device (such as a dumb terminal) to view the initial configuration. From the console port, you can configure other points of entry—such as the VTY line ports—to allow you to use Telnet to configure the switch from other points in your network.

On switches where the console port is an RJ−45 port, you must plug a rolled RJ−45 cable straight into the port. If it is a DB−25 port, you must use an RJ−45−to−DB−25 connector to connect. If the switch uses a DB−9 port, you will need a DB−9−to−RJ−45 connector. Fortunately, these connectors come with every switch—you only need to know which connector and cables to use.

Whatever the type of console port in use on the switch, you will need to connect an RJ−45 cable from the console port or connector to the dumb terminal or PC. On a PC, you can use a third−party program to gain access, such as HyperTerminal (included with most Microsoft Windows operating systems).

Console Cable Pinouts

Two types of RJ−45 cables are used with Cisco switches: a straight−through cable and a rolled cable. To figure out what type of cable you have, hold the two RJ−45 ends side by side. You will see eight colored wires, known as pins, at each end. If the order of the colored pins matches at both ends, then you are holding a straight−through cable. If the colors are reversed, then you are holding a rolled cable.

When a problem occurs, having access to all the accessories to build your own cable is a big advantage. Finding the correct cable or connector on a moment’s notice is not always convenient. I have always wanted a quick reference that lists the pinouts of each cable and connector, so that I could easily make my own cable or connectors. Because I’ve never found such a reference, I’ve created it myself; the lists appear in Tables 2.2 and 2.3.

Table 2.2: Straight−through cable RJ−45−to−RJ−45 pinouts.

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Console Connectors

Different console adapters connect different interfaces in order to connect to the console port. The following are the types of console connectors for each switch:

∙Catalyst 1900, 2820, and 2900 XL series switches each have an RJ−45 console port. You can connect to the console port using a straight−through Category 5 cable.

∙The Catalyst 3000 uses a DB−9 connector to access the console port.

∙The Catalyst 5000 line uses a Supervisor Engine. To connect a console to a Supervisor Engine I or II, use a DB−25 connection. If the switch uses a Supervisor Engine III, use the RJ−45−to−RJ−45

rollover cable.

∙The Catalyst 6000 family also uses a Supervisor Engine with an RJ−45 style connector and an RJ−45−to−RJ−45 straight−through cable.

∙The Catalyst 6500 uses a rolled cable from the console port.

You can use a number of connectors when connecting different devices using your rolled or straight−through cable:

∙To connect a PC to any console cable, attach the RJ−45−to−DB−9 female Data Terminal Equipment (DTE) adapter to one of the nine−pin serial ports on the PC.

∙To attach to a Unix workstation, use the RJ−45−to−DB−25 Data Communications Equipment (DCE) adapter (female).

∙To connect a modem to the console port, use the RJ−45−to−DB−25 (male) adapter.

Note Console port settings by default are 9600 baud, 8 data bits, 1 stop bit, and no parity.

Normally, all three connectors will come with your switch. You will need to use the appropriate adapter for the device with which you are configuring your switch.

Cisco uses two types of RJ−45−to−DB−25 connectors: the DCE style (used for modem connections) and the DTE style (used to connect to terminals or PCs).

The RJ−45−to−AUX Port Console Connector Pinouts

Most often, you will use a connection to a PC or a laptop. The connector signal appointments for each pin on the auxiliary (AUX) port DB−9 connector are shown in Table 2.4. Table 2.5 shows the connector pinouts for an RJ−45−to−DB−9 AUX port connector by color.

Table 2.4: The RJ−45−to−AUX port DB−9 connector signal appointments for each pin.

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Table 2.6 shows the connectors most often used for modem connections. Table 2.7 shows the connectors most often used with Unix workstation connections to the console port.

Table 2.6: DCE connector pinouts for an RJ−45 to a DB−25 male.

Table 2.7: DTE connectors for an RJ−45 to a DB−25 female.

In the event that you need a DB−25−to−DB−9 connector, Table 2.8 shows the pinouts.

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