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You can use the IOS Release 11.2(8)SA6 software to manage a single switch, a group of switches that are managed individually, or a cluster of switches that is managed through a single IP address. You can use any of the management interfaces to manage a switch or cluster. This chapter describes the switching features provided by Release 11.2(8)SA6 and how you can change them. For descriptions of the network-management features and clustering, see "Managing Clusters of Switches."
The graphical user interface of Cisco Visual Switch Manager (CVSM) is the primary focus of this chapter. You can use this interface to monitor a live image of the switch, reconfigure ports and other features, and upgrade the switch software.
Cisco IOS command-line interface (CLI) procedures are included for many tasks in this chapter. However, this guide describes only the use of IOS commands that have been created or changed for use with Catalyst 2900 XL and Catalyst 3500 XL switches. These commands are further described in the Cisco IOS Desktop Switching Command Reference. For information on other IOS Release 11.2(8) commands, see the IOS documentation set available from the CCO home page by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
This chapter also describes the Cisco Switch Network View, hereafter called Network View, an HTML tool that displays a map of the devices that are connected to your switch. From this map you can display the CVSM interface for the other supported switches.
You can configure the features of this IOS release by using any of the available interfaces. Table 3-1 lists the most important features, their defaults, and where they are described in this guide.
| Feature | Default Setting | HTML Interface or Menu Option | IOS CLI Procedure | |
|---|---|---|---|---|
| Network Management |
|
|
| |
| Creating clusters | None | Cluster Builder | |
Removing cluster members | None | Cluster Manager | ||
| Upgrading cluster software | Enabled | Cluster Manager | |
Displaying reports | Enabled | Cluster Manager, Cluster Builder, Cluster View | - | |
| Device Management | ||||
| Switch IP address, subnet mask, and default gateway | 0.0.0.0 | System>IP Management | "CLI Commands for Assigning IP Information to the Switch" section |
Cisco Discovery Protocol (CDP) | Enabled | Device>Cisco Discovery Protocol | Documentation set for Cisco IOS Release 11.2(8) on CCO | |
| Address Resolution Protocol (ARP) | Enabled | System>ARP Table | Documentation set for Cisco IOS Release 11.2(8) on CCO |
| System Time Management | None | System>System Time Management | Documentation set for |
| Static address assignment | None assigned | Security>Address Management | |
| Cisco Switch Network View | Enabled | - | |
| VLAN membership | Static access ports in VLAN 1 | VLAN>VLAN Membership | "CLI Commands for Assigning Static Access Ports to a VLAN" section |
| Performance | ||||
Autonegotiation of duplex mode | Enabled | Port>Port Configuration | "CLI Procedure for Setting Speed and Duplex Parameters" section | |
Autonegotiation of port speeds | Enabled | Port>Port Configuration | "CLI Procedure for Setting Speed and Duplex Parameters" section | |
| Flooding Control |
|
|
| |
Broadcast storm control | Disabled | Port>Flooding Controls | ||
| Flooding unknown unicast and multicast packets | Enabled | Port>Flooding Controls | "CLI Commands for Blocking Flooded Traffic on a Port" section |
| Network port | Disabled | Port>Flooding Controls | |
| Cisco Group Management Protocol (CGMP) | Enabled | Device>Cisco Group Management Protocol | "CLI Commands for Enabling the CGMP Fast Leave Option" section |
| Network Redundancy |
|
|
| |
Spanning-Tree Protocol | Enabled | Device>Spanning-Tree Protocol | ||
Port grouping | None assigned | Port>Port Grouping (EC) | ||
| Diagnostics |
|
|
| |
SPAN port monitoring | Disabled | Port>Switch Port Analyzer (SPAN) | See the documentation set for Cisco IOS Release 11.2(8) on CCO | |
Console, buffer, and file logging | Disabled | Fault>Logging Config | Documentation set for Cisco IOS Release 11.2(8) on CCO | |
| Security |
|
|
| |
Password | None | Visual Switch Manager Home | ||
Addressing security | Disabled | Security>Address Management | ||
Trap manager | 0.0.0.0 | System>SNMP Configuration | Documentation set for Cisco IOS Release 11.2(8) on CCO | |
Community strings | public | System>SNMP Configuration | Documentation set for Cisco IOS Release 11.2(8) on CCO | |
Port security | Disabled | Security>Port Security | Documentation set for Cisco IOS Release 11.2(8) on CCO | |
Certain combinations of port features conflict with one another. For example, if you define a port as the network port for a VLAN, all unknown unicast and multicast traffic is flooded to the port. You could not enable port security on the network port because a secure port limits the traffic allowed on it. In Table 3-2, no means that the two referenced features are incompatible.
If you try to enable incompatible features by using CVSM, CVSM issues a warning message and prevents you from making the change. Reload the web page to refresh CVSM.
| ATM Port1 | Port Group | Port Security | SPAN Port | Multi-VLAN Port | Network Port2 | |
| ATM Port | - | No | No | No | No | No |
| Port Group | No | - | No | No | Yes | Yes |
| Port Security | No | No | - | No | No | No |
| SPAN Port | No | No | No | - | No | No |
| Multi-VLAN Port | No | Yes | No | No | - | Yes |
| Network Port | No | Yes (source-based only) | No | No | Yes | - |
| 1Catalyst 2900 XL only. 2Cannot be used in a cluster. |
The configuration file that loads when the switch is restarted is in Flash memory. This configuration in this file is not necessarily the same as the running configuration. If you want the running (current) configuration to be used when the switch restarts, use CVSM or the CLI to save the configuration file. This procedure is described for CVSM in the "Reloading and Upgrading the Switch Software" section. It is described for the CLI in the "Working with Files in Flash Memory" section.
This section describes the switch Network View, an application that extends web-based network management to the other devices in your network. By exchanging Cisco Discovery Protocol (CDP) messages with attached CDP-enabled devices, a Network View switch is able to graphically display a surrounding star topology that can consist of Catalyst 2900 and Catalyst 3500 series XL switches and Cisco edge devices.
Network View is an alternative to the cluster that you can create by using Cluster Management. Each Network View member needs to be assigned its own IP address. A Network View stack differs from a cluster in that each member has its own IP address assigned to it. In addition, a Network View stack must be in a star topology and does not support daisy-chained switches.
The center node in a star topology acts as a primary switch in Network View. Up to four directly connected supported switches can be stack members. These switches can be displayed in a consolidated physical view called the visual stack. You can access device and link information from the Network View page and the Visual Stack page.
If more than four switches are connected, Network View displays only the four connected to the lowest port numbers of the primary switch. All other devices are considered edge devices. A star topology with the primary switch in the center ensures the most complete view of the network.
To run Network View, all stack members must be running Cisco IOS Release SA6 or later and the corresponding CVSM release. In addition, you need to enable SNMP and set the community string to public on all stack members.
For a complete description of the Network View interface, see "Using Switch Network View" section.
If you have not enabled a command switch, the Network View page (Figure 3-1) displays a map of the devices and links that are directly connected to your switch. From this page, you can display switch-connection information, device reports, and link reports. This page also displays Cisco routers, switches, hubs, and Cisco Micro Web Servers, but these devices must be directly attached to one of the supported switches. Other devices using CDP display as generic edge devices.
Follow these steps to display the Network View page:
Step 1 On the Switch Manager home page, click Switch Network View.
Step 2 When prompted, enter the enable password for each switch in the stack. You do not need to enter a user name.
Figure 3-2 shows the information that you can display about the switches being managed by Network View. Click on the Switch Manager button on the Network View page to display this table.
The visual stack is an image of up to four Catalyst 2900 series XL or Catalyst 3500 series XL switches (Figure 3-3) with the primary switch at the top. This stack contains the same switches as those on the Network View page, which displays the primary switch in the middle and stack members connected to it. The stack images display real-time information about the switches and their ports. You can use the stack to monitor port status, check port speed and duplex settings, configure switch ports, and start the CVSM software.
Follow these steps to display the Visual Stack page:
Step 1 Display the Network View page as described in the "Displaying the Network View Page" section.
Step 2 Click Visual Stack in the upper-left corner of the page.
The visual stack displays in a separate browser window (see Figure 3-3).
The visual stack shows LED colors to depict the port status:
To check the transmission speed settings for all switch ports, click MODE, and highlight SPD (speed). Blue means 10 Mbps; green means 100 Mbps.
To check the duplex setting, click MODE, and highlight FDUP (full-duplex). Blue means half-duplex mode; green means full-duplex mode.
On the visual stack, click on a port and right-click to display the pop-up menu. Select Port Configuration. The Port Configuration pop-up window shows the port settings and status. Select Enable to enable or disable the port and STP Port Fast setting, and select a speed and duplex setting from the drop-down lists. This window is the same as the one described in the "Configuring Ports on the Switch Home Page" section.
In addition, you can configure multiple ports as a group. To do so, press Ctrl and left-click the ports, and then right-click the selected ports and select Port Configuration from the pop-up menu.
The visual stack displays the IP address of each switch next to the switch image. Click the IP address to open a separate browser window displaying the CVSM home page for that switch. End the browser session when you want to return to the visual stack.
You access CVSM through one of the supported browsers described in the "Hardware and Software Requirements" section. Ensure that you have the browser configured correctly before starting CVSM.
The Cisco Visual Switch Manager Home page (Figure 3-4) is always displayed when you click Visual Switch Manager on the Cisco Systems Access page. All the CVSM pages have a Home button you can click to return to this page.
Use this page to perform the following tasks:
Changing the password from this page breaks your connection with the switch, and the browser prompts you for the new password. Click Help for the complete procedure. If you have forgotten your password, see the "Recovering from a Lost or Forgotten Password" section.
If the switch is command-capable, use this page to enable it as the command switch and to name the cluster. The Cluster Management button displays on the home page after the command switch is enabled, and the cluster name appears in Cluster View with the cluster icon. Table 1-1 in "Introduction," lists the switches that are able to be command switches and those that can be enabled by a software upgrade.
The CVSM home page refreshes the image of the switch every 30 seconds. Besides using it to configure the features listed in this section, you can use the switch images in Cluster Manager to display VLAN membership information and detailed information about the links between switches. For more information on monitoring the switch via a web interface, see the "Managing Clusters of Switches."
The other LEDs function as follows:
To configure a port, left-click on it and then right-click to display the pop-up menu. Select Port Configuration. Press+ Ctrl and left-click the ports to select more than one at a time. The dialog box shown in Figure 3-5 displays the same information and supports the same changes as the Port Configuration page. The live LEDs on the image of the switch reflect any changes you make.
This IOS release supports 10/100, Gigabit Ethernet, ATM, and Catalyst GigaStack Gigabit Interface Converters (GBICs). See the "Configuring Port Parameters" section for defaults and guidelines for configuring the different types of ports.
Use this page to enable and disable ports and to set the duplex, speed and Port Fast parameters. Select Port>Port Configuration from the menu bar.
Figure 3-6 shows the Port Configuration page, and Table 3-3 describes the meaning of column headings and fields. The "Configuring Port Parameters" section contains guidelines for you to use when using this page.
Port | Displays Fa (Fast Ethernet), Gi (Gigabit Ethernet), or AT (ATM); the module number: 0 (fixed), 1 (right slot), or 2 (left slot); and the port number. In Figure 3-5, the port is a fixed port (0) and port number 14: Fa0/14. Note The port numbers for the double-row connectors on the Catalyst 3500 series XL switches increment from top to bottom. |
Status: Admin/Actual | Enables or disable the port. The field also displays the current port status. |
Duplex: Requested/Actual | Displays the current duplex setting. You can set a port to full-duplex (Full), half-duplex (Half), or autonegotiate (Auto). The default is Auto. For ATM ports, this field is read-only and displays Full. |
Speed: Requested/Actual | Displays the current speed setting. You can set a port to 10 Mbps (10), 100 Mbps (100), or autonegotiate (Auto). The default is Auto. For Gigabit Ethernet ports, the field displays 1000 and is read-only. For ATM ports, the field displays 155 (155 Mbps) and is read-only. |
Port Name | Names the port or describes how it is connected. |
Statistics | Displays transmit and receive statistics for the port. Click Reset to clear the statistics and close the statistics window. |
Flow Control | Enables or disables flow control on Gigabit Ethernet ports. Flow control enables the connected Gigabit Ethernet ports to control traffic rates during congestion. If one port experiences congestion and cannot receive any more traffic, it notifies the other port to stop transmitting until the condition clears. Select Symmetric when you want the local port to perform flow control of the remote port only if the remote port can also perform flow control on the local port. Select Asymmetric when you want the local port to perform flow control on the remote port. For example, if the local port is congested, it notifies the remote port to stop transmitting. This is the default setting Select Any when the local port can support any level of flow control required by the remote port. This setting is the default. Select None to disable flow control on the port. This field is displayed only when a Gigabit Ethernet port is present; it does not apply to Fast Ethernet or ATM ports. |
The Port Configuration page displays the Requested and Actual settings for each port. A port connected to a device that does not support the requested setting or that is not connected to a device can cause the Requested and Actual settings to differ.
 | Caution It is possible to reconfigure the port through which you are managing the switch. STP reconfiguration could cause a temporary loss of connectivity. |
Follow these guidelines when configuring the duplex and speed settings:
To connect to a remote 100BaseT device that does not autonegotiate, do not configure AUTO for the duplex setting on the local device. Autonegotiation of the speed setting works correctly even if the attached device does not autonegotiate.
To connect to a remote Gigabit Ethernet device that does not autonegotiate, disable Autonegotiation on the local device, and set the duplex and flow control parameters to be compatible with the other device. For more information, see the "Identifying an Autonegotiation Mismatch" section.
Beginning in privileged EXEC mode, follow these steps to set the speed and duplex parameters on a port:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to be configured. | interface interface |
Step 3 Enter the speed parameter for the port. You cannot enter the speed on Gigabit Ethernet or ATM ports. | speed {10 | 100 | auto} |
Step 4 Enter the duplex parameter for the port. | duplex {full | half | auto} |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify your entries. | show running-config |
Step 7 (Optional) Save your entry in the configuration file. This retains the configuration when the switch restarts. | copy running-config startup-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Port Group (EtherChannel) page (see Figure 3-8) to create Fast EtherChannel and Gigabit EtherChannel port groups. These port groups act as single logical ports for high-bandwidth connections between switches or between switches and servers.
To display this page, select Port>Port Grouping (EC) from the menu bar.
This IOS release supports two different types of port groups: source-based forwarding port groups and destination-based forwarding port groups. Source-based forwarding ports groups distribute packets forwarded to the group based on the source address of incoming packets from ports that are not in the port group. Port groups that forward based on the source address can have as many as eight ports. Source-based forwarding is enabled by default.
Destination-based port groups distribute packets forwarded to the group based on the destination address of incoming packets from ports not in the group. Port groups that forward based on the destination address can have any number of ports.
Port groups that link switches each switch, but both ends of a port group must be configured consistently. In Figure 3-7, a port group of two workstations communicates with a router. Because the router is a single-MAC address device, source-based forwarding ensures that the switch uses all available bandwidth to the router. The router is configured to forward based on destination address because the larger number of stations ensures that the traffic is evenly distributed out the port-group ports on the router.
The switch treats the port group as a single logical port; therefore, when you create a port group, the switch uses the configuration of the first port for all ports added to the group. If you add a port and change the forwarding method, it changes the forwarding for all ports in the group. After the group is created, changing STP or VLAN membership parameters for one port in the group automatically changes the parameters for all ports. Each port group has one port that carries all unknown multicast, broadcast, and STP packets.
The following restrictions apply to entering static addresses that are forwarded to port groups:
Beginning in privileged EXEC mode, complete these tasks to create a two-port group:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port of the first port to be added to the group. | interface interface |
Step 3 Assign the port to group 1 with destination-based forwarding. | port group 1 distribution destination |
Step 4 Enter the second port to be added to the group. | interface interface |
Step 5 Assign the port to group 1 with destination-based forwarding. | port group 1 distribution destination |
Step 6 Return to privileged EXEC mode. | end |
Step 7 Verify your entries. | show running-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Switch Port Analyzer (SPAN) page (Figure 3-9) to enable port monitoring. You can monitor traffic on a given port by forwarding incoming and outgoing traffic on the port to another port in the same VLAN. A SPAN port cannot monitor ports in a different VLAN, and a SPAN port must be a static-access port. Any number of ports can be defined as SPAN ports, and any combination of ports can be monitored.
To display this page, select Port>Switch Port Analyzer (SPAN) from the menu bar.
For the restrictions that apply to SPAN ports, see the "Managing Configuration Conflicts" section.
Use the Flooding Controls page (Figure 3-10) to block the forwarding of unnecessary flooded traffic. You can enable three flooding techniques from this page:
To display this page, select Port>Flooding Controls from the menu bar.
Network ports are assigned per VLAN and can reduce flooded traffic on your network. The switch forwards all traffic with unknown destination addresses to the network port instead of flooding the traffic to all ports in the VLAN.
When you configure a port as the network port, the switch deletes all associated addresses from the address table and disables learning on the port. If you configure other ports in the VLAN as secure ports, the addresses on those ports are not aged. If you move a network port to a VLAN without a network port, it becomes the network port for the new VLAN.
You cannot change the settings for unicast and multicast flooding on a network port.
| Caution A network port cannot link cluster members. Do not attempt to connect cluster members through a network port. |
For limitations on configuring a network port, see the "Managing Configuration Conflicts" section.
Beginning in privileged EXEC mode, complete these tasks to define a port as the network port:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to be configured. | interface interface |
Step 3 Define the port as the network port. | port network |
Step 4 Return to privileged EXEC mode. | end |
Step 5 Verify your entry. | show running-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
A broadcast storm occurs when a large number of broadcast packets are received. Forwarding these packets can cause the network to slow down or to time out. Broadcast storm control is configured for the switch as a whole, but operates on a per-port basis. By default, broadcast storm control is disabled.
Broadcast storm control uses specific high and low numbers of broadcast packets to block and then to restore forwarding of broadcast packets. In general, the higher the threshold, the less effective the protection against broadcast storms. The maximum half-duplex transmission on a 100BaseT link is 148,000 packets per second, but you can enter a threshold up to 4294967295 broadcast packets per second.
Beginning in privileged EXEC mode, follow these steps to enable broadcast-storm control.
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to configure. | interface interface |
Step 3 Enter the rising and falling thresholds. | port storm-control [threshold {rising rising-number falling falling-number}] |
Step 4 Disable the port during a broadcast storm, or generate an SNMP trap when the traffic on the port crosses the rising or falling threshold. | port storm-control filter or port storm-control trap |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify your entries. | show port storm-control [interface] |
By default, the switch floods packets with unknown destination MAC addresses to all ports. Some configurations do not require flooding. For example, a port that has only manually assigned addresses has no unknown destinations, and flooding serves no purpose. Therefore, you can disable the flooding of unicast and multicast packets on a per-port basis. Ordinarily, flooded traffic does not cross VLAN boundaries, but multi-VLAN ports flood traffic to all VLANs they belong to.
To display the page for blocking flooded traffic, select Port>Flooding Controls from the menu bar.
Beginning in privileged EXEC mode, follow these steps to disable the flooding of multicast and unicast packets to a port:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to configure. | interface interface |
Step 3 Block multicast forwarding to the port. | port block multicast |
Step 4 Block unicast flooding to the port. | port block unicast |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify your entries, entering the appropriate command once for the multicast option and once for the unicast option. | show port block {multicast | unicast} interface |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the System Configuration page (see Figure 3-11 and Figure 3-12) to specify the Flash memory filenames that the switch uses when it starts or resets. You can also use this page to upgrade your switch firmware.
To display this page, select System>System Configuration from the menu bar.
You can use this page for the following tasks:
The startup configuration file contains the IP addresses, passwords, and any other information you entered. The switch reloads this file when it restarts. However, the startup configuration file might not be the running (current) configuration. Changes made through the CVSM or the CLI take effect immediately but must be explicitly saved to be included in the startup configuration.
Use this page to save the running configuration to the startup configuration file. The following buttons control the switch startup:
Save Configuration | Click to write the running configuration to Flash memory. This configuration is then loaded when the switch is restarted. |
Reboot System | Click to restart the switch and to load the new startup configuration. |
By default, the System Reload Options fields contain the correct information to reboot the system. Some of the fields contain files in Flash memory. To determine the filenames to use, enter the following EXEC mode command at the CLI:
switch# dir flash: Directory of flash: 2 -rwx 843947 Mar 01 1993 00:02:18 C2900XL-hs-mz-112.8-SA6.bin 4 drwx 3776 Mar 01 1993 01:23:24 html 66 -rwx 130 Jan 01 1970 00:01:19 env_vars 68 -rwx 1296 Mar 01 1993 06:55:51 config.text 1728000 bytes total (456704 bytes free)
The image file that runs the switch has a .bin extension, the html directory contains the CVSM HTML files, and config.text contains the current configuration. If you need more information about accessing the switch via the CLI, refer to the "Configuring the Switch for Telnet" section.
Click Help for procedures on how to configure the fields on this page.
When you upgrade a switch or cluster, the switch or switches continue to operate normally while the new software is copied to Flash memory. When the copy is complete, the old files are deleted, and the new software is loaded the next time you reboot. If the browser halts or the copy fails in some way, you can reboot the switch with the old version of the software and re-execute the upgrade procedure.
If you group switches into a cluster, you can upgrade the entire cluster from Cluster Manager. For more information, see the "Upgrading Software for a Group of Switches" section.
New releases of switch software are available on Cisco Connection Online (CCO). The process of upgrading your switch consists of the following steps:
Step 1 Downloading the software from CCO.
Step 2 Downloading a TFTP server if necessary.
Step 3 Entering the name of the new image on this page and clicking Upgrade Cisco IOS and Visual Switch Manager.
Click Help for the complete procedures for this process.
This procedure is for switches already running IOS Release 11.2(8)SA6. Switches running earlier IOS releases might have less memory and require slightly different procedures. If you need to upgrade an older switch to this IOS release, refer to the Release Notes for Cisco IOS Release 11.2(8)SA6 or the release notes that came with your switch.
These steps are included in the upgrade procedure:
Follow these steps to upgrade the switch software, starting in privileged EXEC mode:
| Task | Command | ||||
|---|---|---|---|---|---|
| switch# show boot | ||||
| switch# rename flash:current_image flash:new_image.bin | ||||
| switch# dir flash: | ||||
| switch# configure terminal | ||||
| switch(config)# no IP http server | ||||
| switch(config)# end | ||||
| switch# delete flash:html/* | ||||
| switch# tar /x tftp://server_ip_address//path/filename.tar flash: | ||||
| switch# configure terminal | ||||
| switch(config)# IP http server | ||||
| switch(config)# end | ||||
| switch# reload |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the System Time Management page (Figure 3-13) to set the system time for a switch or enable an external source such as Network Time Protocol (NTP) to supply time to the switch.
You can use this page to set the switch time by using one of the following techniques:
To display this page, select System>System Time Management from the menu bar.
Enter the date and a 24-hour clock time setting on the System Time Management page. If you are entering the time for an American time zone, enter the three-letter abbreviation for the time zone in the Name of Time Zone field. If you are identifying the time zone by referring to Greenwich Mean Time, enter UTC (Universal Time Coordinated) in the Name of Time Zone field. You then must enter a negative or positive number as an offset to indicate the number of time zones the switch is from Greenwich, England. Enter a negative number if the switch is west of Greenwich, England, and east of the International Date Line. California is eight time zones west of Greenwich, and you would enter -8 in the Hours Offset From UTC field. Negative and positive numbers can also be entered for minutes.
In complex networks it can make sense to distribute time information from a central server. The NTP can distribute time information by responding to requests from clients or by broadcasting time information. You can use the Network Time Protocol page (Figure 3-14) to enable these options and to enter authentication information to accompany NTP client requests.
To display this page, click Configure NTP on the System Time Management page.
You configure the switch as an NTP client by entering the IP addresses of up to ten NTP servers in the IP Addr field. Click Preferred to specify which server should be used first. You can also enter an authentication key to be used as a password when requests for time information are sent to the server.
To ensure the validity of information received from NTP servers, you can authenticate NTP messages with public-key encryption. This procedure must be coordinated with the administrator of the NTP servers: the information you enter on this page will be matched by the servers to authenticate it.
Click Help for more information about entering information in the Key Number, Key Value, and Encryption Type fields.
You can configure the switch to receive NTP broadcast messages if there is an NTP broadcast server, such as a router, broadcasting time information on the network. You can also enter a delay in the Estimated Round-Trip Delay field to account for round-trip delay between the client and the NTP broadcast server.
Use the IP Management page (see Figure 3-15) to change or enter IP information for the switch. Some of this information, such as the IP address, you had previously entered.
To change IP information for the switch, select System>IP Management from the menu bar.
The switch IP address belongs to VLAN 1 and is used to access interfaces such as the CVSM and SNMP. For a port to access one of these management interfaces, it must also belong to VLAN 1.
If your switch is configured as a member switch in a cluster, it might not have an IP address assigned to it. If your switch is configured as a command switch in a cluster, its IP information supports the IP connectivity of all its member switches.
| Caution Changing the switch IP address on this page ends your CVSM session. Restart the CVSM by entering the new IP address in the browser Location field (Netscape Communicator) or Address field (Internet Explorer), as described in the "Using Cisco Visual Switch Manager" section. |
Beginning in privileged EXEC mode, follow these steps to enter the IP information:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to which the IP information is assigned. | interface vlan 1 |
Step 3 Enter the IP address and subnet mask. | ip address ip_address subnet_mask |
Step 4 Enter the IP address of the default router. | ip default-gateway ip_address |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify that the information was entered correctly by displaying the running configuration. If the information is incorrect, repeat the procedure. | show running-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the SNMP Configuration page (Figure 3-16) to configure your switch for SNMP management.
To display this page, select System>SNMP Configuration from the menu bar.
This guide describes the use of IOS commands that have been created or changed for use with switches that support IOS Release 11.2(8)SA6. For information on other IOS Release 11.2(8) commands, see the IOS documentation set available from the CCO home page by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use this page to perform the following tasks:
If you deselect Enable SNMP and click Apply, SNMP is disabled, and the SNMP parameters on the page disappear. SNMP must be enabled for some network view and Cluster Management features to work properly. For information SNMP and Cluster Management, see "Managing Clusters via SNMP" section.
Community strings serve as passwords for SNMP messages. You can enter them with the following characteristics:
Read only (RO) | Requests accompanied by the string can display MIB-object information. |
Read write (RW) | Requests accompanied by the string can display MIB-object information and set MIB objects. |
A trap manager is a management station that receives and processes traps. When you configure a trap manager, community strings for each member switch must be unique. If a member switch has an IP address assigned to it, the management station accesses the switch via the IP address.
By default, no trap manager is defined, and no traps are issued.
Select a check box to enable on of the following classes of traps:
Send config traps | Generate traps whenever the switch configuration changes. |
Send SNMP traps | Generate the supported SNMP traps. |
Send TTY traps | Generate traps when the switch starts a management console CLI session. |
Send C2900, C3500 traps | Generate the switch-specific traps. These traps are in the private enterprise-specific MIB. |
Send VTP traps | Generate a trap for each VLAN Trunk Protocol (VTP) change (Enterprise Edition Software only). |
Send VLAN membership traps | Generate a trap for each VLAN Membership Policy Server (VMPS) change (Enterprise Edition Software only). |
Beginning in privileged EXEC mode, follow these steps to add a trap manager and community string:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | config terminal |
Step 2 Enter the trap manager IP address, community string, and the traps to generate. | snmp-server host 172.2.128.263 traps1 snmp vlan-membership |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify that the information was entered correctly by displaying the running configuration. | show running-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the ARP Table page (Figure 3-18) to display the table and change the timeout value. The Address Resolution Protocol (ARP) discovers the MAC address and VLAN ID that corresponds to a host IP address. Figure 3-19 shows the meaning the of ARP table contents.
To display this page, select System>ARP Table from the menu bar. ARP entries added manually to the table do not age and must be manually removed.
This guide describes the use of IOS commands that have been created or changed for use with switches that support IOS Release 11.2(8)SA6. For information on other IOS
Release 11.2(8) commands, see the IOS documentation set available from the CCO home page by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Address Management page (see Figure 3-21) to manage the MAC address tables that the switch uses to forward traffic between ports. These MAC tables include the dynamic, secure, and static addresses.
To display this page, select Security>Address Management from the menu bar.
The address tables list the destination MAC address and the associated VLAN ID, module, and port number associated with the address. Figure 3-20 shows a list of dynamic addresses.
All addresses are associated with a VLAN. An address can exist in more than one VLAN and have different destinations in each. Multicast addresses, for example, could be forwarded to port 1 in VLAN 1 and ports 9, 10, and 11 in VLAN 5. A known address in one VLAN is unknown in another until it is learned or statically associated with a port in the other VLAN.
An address can be secure in one VLAN and dynamic in another. Addresses that are statically entered in one VLAN must be static addresses in all other VLANs. Each VLAN maintains its own logical address table.
Dynamic addresses are source MAC addresses that the switch learns and then drops when they are not in use. Use the Aging Time field to define how long the switch retains unseen addresses in the table. This parameter applies to all VLANs.
Beginning in privileged EXEC mode, follow these steps to define the aging time for the address table.
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter the number of seconds that dynamic addresses are to be retained in the address table. You can enter a number from 10 to 1000000. | mac-address-table aging-time seconds |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify your entry. | show mac-address-table aging-time |
You can enter a secure port address even when the port does not yet belong to the VLAN. When the port is later assigned to the VLAN, packets destined for that address are forwarded to the port.
To display this page, select Security>Address Management from the menu bar.
After you have entered the secure address, select Security>Port Security from the menu bar to secure the port on the Port Security page.
Beginning in privileged EXEC mode, follow these steps to enter a secure address:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter the MAC address, its associated port, and the VLAN ID. | mac-address-table secure hw-addr interface |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify your entry. | show mac-address-table secure |
A static address has the following characteristics:
The Static Address Forwarding map (Figure 3-22) displays when you enter a static address. Use this page to define those ports that frames are forwarded to based on the port on which they were received. Because all ports are associated with at least one VLAN, the switch acquires the VLAN ID for the address from the ports that you select on the forwarding map.
The Rx On column on the left lists the source ports. The Forward to columns across the page are the destination ports. Ports without check boxes belong to VLANs that a source port cannot access.
A static address in one VLAN must be a static address in other VLANs. A packet with a static address that arrives on a VLAN where it has not been statically entered is flooded to all ports and not learned.
To display this page, select Security>Address Management from the menu bar, and enter or select an address in the Static Address Table.
Follow these rules if you are configuring a static address to forward to ports in an EtherChannel port group:
Static addresses are entered in the address table with an in-port-list and an out-port-list and, as needed, a VLAN definition. Packets received from the in-port are forwarded to ports listed in the out-port-list.
Beginning in privileged EXEC mode, follow these steps to enter a static address:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter the MAC address, the input port, the ports to which it can be forwarded, and the VLAN ID of those ports. | mac-address-table static hw-addr in-port out-port-list vlan vlan-id |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify your entry. | show mac-address-table static |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2Cisco IOS Release 11.2.
Use the Port Security page (Figure 3-23) to enable port security and to define the size of the secured port address table.
To display this page, select Security>Port Security from the menu bar.
Secured ports generate address-security violations under the following conditions:
Limiting the number of devices that can connect to a secure port has the following advantages:
The following fields validate port security or indicate security violations:
Secure Addresses | The number of addresses in the address table for this port. Secure ports have at least one in this field. |
Security Rejects | The number of unauthorized addresses seen on the port. |
The port features that are unavailable to secure ports are described in the "Preparing to Use the Web-Based Management Interfaces" section.
The following example shows the commands for enabling port security and setting the port to learn only one address. This procedure disables the port if a security violation occurs. Starting in privileged EXEC mode, follow these steps to enable port security.
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode for the port you want to secure. | interface interface |
Step 3 Secure the port and set the address table to one address. | port security max-mac-count 1 |
Step 4 Set the port to shutdown when a security violation occurs. | port security shutdown |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify the entry. | show port security |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Cisco Discovery Protocol (CDP) page to enable CDP for the switch, set global CDP parameters, and display information about neighboring Cisco devices. CDP enables CVSM and other network management applications to display a graphical network view of the network. For example, the switch uses CDP to find cluster candidates and maintain information about cluster members and other devices. The information exchanged in CDP messages includes the device type, links between devices, and the number of ports within each device. Based on the CDP messages sent, the switch displays these devices in the network view and the Cluster Manager.
To display this page (see Figure 3-24), select Device>Cisco Discovery Protocol from the menu bar.
Some CDP options are global to the switch, and some are entered on a per-port basis. CDP is enabled by default. Click Help for the defaults and possible values of the fields on this page. You can use this page for the following tasks:
This guide describes the use of IOS commands that have been created or changed for use with switches that support IOS Release 11.2(8)SA6. For information on other IOS Release 11.2(8) commands, see the IOS documentation set available from the CCO home page by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Cisco Group Management Protocol page (see Figure 3-25) to enable Cisco Group Management Protocol (CGMP) and the CGMP Fast Leave option. CGMP reduces the unnecessary flooding of IP multicast packets by limiting the transmission of these packets to CGMP clients that request them. The Fast Leave option accelerates the removal of unused CGMP groups. By default, CGMP is enabled, and the Fast Leave option is disabled.
To display this page, select Device>Cisco Group Management Protocol from the menu bar.
End stations issue join messages to become part of a CGMP group and issue leave messages to leave the group. The membership of these groups is managed by the switch and connected routers through the further exchange of CGMP messages.
CGMP groups are maintained by VLAN: a multicast IP address packet can be forwarded to one list of ports in one VLAN and to a different list of ports in another VLAN. When a CGMP group is added or removed, all members are in the same VLAN.
You can use this page to perform the following tasks:
The CGMP Fast Leave option reduces the delay when group members leave groups. When an end station requests to leave a CGMP group, the group remains enabled for that VLAN until all members have requested to leave. With the Fast Leave option enabled, the switch immediately checks if there are other members that belong to that group. If there are no other members, the switch removes the port from the group. If there are no other ports in the group, the switch sends a message to routers connected to the VLAN to delete the entire group.
CGMP reduces flooding by limiting the forwarding of IP multicast and broadcast packets. The Fast Leave option reduces the time CGMP uses to remove inactive groups.
Beginning in privileged EXEC mode, complete these tasks to enable CGMP Fast Leave option:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enable CGMP and CGMP Fast Leave. | cgmp leave-processing |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify your entry. | show running-config |
The router hold time is the number of seconds the switch waits before removing (aging) a router entry and ceasing to exchange messages with it. If it is the last router entry on a VLAN, then all groups on that VLAN are removed. You can thus enter a lower number in the Router Hold Time field to accelerate the removal of CGMP groups.
Beginning in privileged EXEC mode,
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Configure the number of seconds the switch is to wait before dropping a router entry. | cgmp holdtime 400 |
Step 3 Return to privileged EXEC mode. | end |
Step 4 Verify your entry. | show running-config |
You can reduce the forwarding of IP multicast packets by removing groups from the Current Multicast Groups table. Each entry in the table consists of the VLAN, IGMP multicast address, and ports.
You can use the CLI to clear all CGMP groups, all CGMP groups in a VLAN, or all routers, their ports, and their expiration times. Beginning in privileged EXEC mode, follow these steps to remove all multicast groups.
| Task | Command |
|---|---|
Step 1 Clear all CGMP groups on the switch. | clear cgmp group |
Step 2 Verify your entry by displaying CGMP information. | show cgmp |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Spanning-Tree Protocol (STP) page (Figure 3-26) to change parameters for STP, an industry standard for avoiding loops in switched networks. The switch supports up to
64 instances of STP.
To display this page, select Device>Spanning-Tree Protocol from the menu bar.
Because each VLAN has its own instance of STP, you must first select a VLAN ID, and then click Modify STP Parameters to display the rest of the page.
This page is shown in three illustrations. Figure 3-26 shows the page with no parameters; Figure 3-27 shows the parameters currently used by the switch and the parameters that this switch would use if it became the root switch. Figure 3-28 shows the fields that you use to define port-level parameters.
You can create a redundant backbone with STP by connecting two of the switch ports to another device or to two different devices. STP automatically disables one port, but enables it if the other port is lost. If one link is high-speed and the other low-speed, the low-speed link is always disabled. If the speed of the two links is the same, the port priority and port ID are added together, and STP disables the link with the lowest value.
You can also create redundant links between switches by using EtherChannel port groups. See the "Creating EtherChannel Port Groups" section for more information on creating port groups.
Because each VLAN is a separate instance of STP, the switch accelerates aging on a per-VLAN basis. A reconfiguration of STP on one VLAN can cause the dynamic addresses learned on that VLAN to be subject to accelerated aging. Dynamic addresses on other VLANs can be unaffected and remain subject to the aging interval entered for the switch.
STP is enabled by default. Disable STP only if you are sure there are no loops in the network topology. With STP disabled and loops present in the topology, network performance is degraded by excessive traffic and indefinite packet duplication.
To change STP parameters for a VLAN, select Device>Spanning-Tree Protocol from the menu bar, select the VLAN ID of the STP instance to change, and click Modify STP Parameters.
In Figure 3-27, the parameters under the heading Current Spanning-Tree Root are read-only and could be defined on another switch. The MAC Address field shows the MAC address of the switch currently acting as the root. The parameters under the heading Spanning-Tree Options are the values that this switch would use as the root switch.
The following fields (see Figure 3-27) define how your switch responds when STP reconfigures itself.
Protocol | Implementation of STP to use. Select one of the menu items: DEC, IBM, or IEEE. The default is IEEE. |
Priority | Value used to identify the root bridge. The bridge with the lowest value has the highest priority and is selected as the root. Enter a number from 0 to 65535. |
Max age | Number of seconds a bridge waits without receiving STP configuration messages before attempting a reconfiguration. This parameter takes effect when a bridge is operating as the root bridge. Bridges not acting as the root use the root-bridge Max age parameter. Enter a number from 6 to 200. |
Hello | Number of seconds between the transmission of STP configuration messages. Bridges not acting as a root bridge use the root-bridge Hello-time value. Enter a number from 1 to 10. |
Forward Delay | Number of seconds a port waits before changing from its STP learning and listening states to the forwarding state. This wait is necessary so that other switches on the network ensure no loop is formed before they allow the port to forward packets. Enter a number from 4 to 200. |
The ports listed on this page belong to the VLAN selected at the top of the page.
To change STP options port options, select Device>Spanning-Tree Protocol from the menu bar, select the VLAN ID, and click Modify STP Parameters.
A lower path cost represents higher-speed transmission. This can affect which port remains enabled in the event of a loop. Enter a number from 1 to 65535. The default is 100 for 10 Mbps, 19 for 100 Mbps, 14 for 155 Mbps (ATM), 4 for 1 Gbps, 2 for 2 Gbps, and 1 for interfaces with speeds greater than 10 Gbps. | |
Number used to set the priority for a port. A higher number has higher priority. If you are using a DEC-type-STP, enter a number from 0 to 255. If you are using an IEEE-type-STP, enter a number from 0 to 65535. |
Use the following fields (see Figure 3-28) to check the status of ports that are not forwarding due to STP:
Port | The interface and port number. FastEthernet0/1 refers to port 1x. |
State | The current state of the port. A port can be in one of the following states: |
| Port is not participating in the frame-forwarding process and is not learning new addresses. |
| Port is not participating in the frame-forwarding process, but is progressing towards a forwarding state. The port is not learning addresses. |
| Port is not forwarding frames but is learning addresses. |
| Port is forwarding frames and learning addresses. |
| Port has been removed from STP operation. |
The Port Fast option brings a port directly from a blocking state into a forwarding state. The only time a port with the Port Fast option enabled goes through the normal cycle of STP status changes is when the switch is restarted. Use this option when a port is connected to a workstation or server and cannot contribute to bridging loops.
| Caution Enabling this option on a port connected to a switch or hub could prevent STP from detecting and disabling loops in your network. |
Enabling this option on a port connected to a switch or hub could prevent STP from detecting and disabling loops in your network. Beginning in privileged EXEC mode, follow these steps to enable the Port Fast option:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to be configured. | interface interface |
Step 3 Enable the Port Fast feature for the port. | spanning-tree portfast |
Step 4 Return to privileged EXEC mode. | end |
Step 5 Verify your entry. | show running-config |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the VLAN Membership page (Figure 3-29) to assign ports to VLANs.
To display this page, select VLAN>VLAN Membership from the menu bar.
A VLAN is a switched network that is logically segmented by function, project team, or application, without regard to the physical locations of the users. Any switch port can belong to a VLAN, and unicast, broadcast, and multicast packets are forwarded and flooded only to those stations within the VLAN. Each VLAN is considered a logical network, and packets destined for stations that do not belong to the VLAN must be forwarded through a router or bridge.
Because a VLAN is considered a separate logical network, it contains its own bridge MIB information and can support its own implementation of the Spanning-Tree Protocol (STP). The following switches can support up to 250 VLANs, but there only 64 possible instances of STP:
WS-C3524-XL-EN | WS-C3508G-XL-EN |
WS-C3524-XL-A | WS-C2912MF-XL |
WS-C3512-XL-EN | WS-C2924M-XL-A |
WS-C3512-XL-A | WS-C2924M-XL-EN |
WS-C3508G-XL-A |
|
All other switches supported by this IOS release can support 64 VLANs. VLANs are identified with a number between 1 and 1001.
When a port belongs to a VLAN, the switch learns and manages the addresses associated with the port on a per-VLAN basis. See the "Managing the MAC Address Tables" section for more information.
A port can be in one of these modes:
When you assign a port to a VLAN, you define the port as a multi-VLAN or a static-access port and enter a VLAN ID for it. If you change the VLAN ID on a port that belongs to a port group, the VLAN ID for all the ports in that group is also changed.
Beginning in privileged EXEC mode, follow these steps to assign a port for static-access VLAN membership:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to be added to the VLAN. | interface interface |
Step 3 Enter the VLAN membership mode for static-access ports. | switchport mode access |
Step 4 Assign the port to a VLAN. | switchport access vlan 2 |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify your entries. | show interface interface-id switchport |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Using the ATM module CLI, you can map the LAN emulation (LANE) client to a VLAN or bind one or more permanent virtual connections (PVCs) to a VLAN. The VLAN ID is then displayed in the Assigned VLANs column of the VLAN Membership page. Using standard edition software, an ATM port can only be a static-access port. Using Enterprise Edition Software, an ATM port can only be a trunk port. An ATM port can never be a multi-VLAN port.
A multi-VLAN port connected to a router can link two or more VLANs. Intra-VLAN traffic stays within the boundaries of the respective VLANs, and connectivity between VLANs is via the router connected to the multi-VLAN port, as shown in Figure 3-30.
A multi-VLAN port functions normally in all its assigned VLANs. For example, when a multi-VLAN port receives an unknown MAC address, all the VLANs to which the port belongs learn the address. Multi-VLAN ports also respond to the STP messages generated by the different instances of STP in each VLAN.
| Caution Avoid unpredictable STP behavior by strictly limiting the connection of multi-VLAN ports to routers or servers. |
To avoid loss of connectivity, do not connect multi-VLAN ports to hubs or switches. Connect multi-VLAN ports to routers or servers.
Beginning in privileged EXEC mode, follow these steps to assign ports for multi-VLAN membership:
| Task | Command |
|---|---|
Step 1 Enter global configuration mode. | configure terminal |
Step 2 Enter interface configuration mode, and enter the port to be added to the VLAN. | interface interface |
Step 3 Enter the VLAN membership mode for multi-VLAN ports. | switchport mode multi |
Step 4 Assign the port to more than one VLAN. | switchport multi vlan add vlan-list |
Step 5 Return to privileged EXEC mode. | end |
Step 6 Verify your entries. | show interface interface-id switchport |
For more information on IOS Release 11.2(8)SA6, see the Cisco IOS Desktop Switching Command Reference. The complete IOS Release 11.2(8) documentation is available through CCO by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2.
Use the Logging Configuration page (Figure 3-31 and Figure 3-32) to define the logging type and the severity level of information that the switch logs. The switch can generate log messages when the configuration changes and when certain network or switch events occur.
To display this page, select Fault>Logging Config from the menu bar.
This guide describes the use of IOS commands that have been created or changed for use with switches that support IOS Release 11.2(8)SA6. For information on other IOS Release 11.2(8) commands, see the IOS documentation set available from the CCO home page by selecting Service and Support>Technical Documents>Documentation Home Page>Cisco IOS Software Configuration>Cisco IOS Release 11.2Cisco IOS Release 11.2.
You can select one of the following options for recording log information:
Console Logging | Write log information to the management console. |
Buffer Logging | Write log information to a buffer in Flash memory. Enter the size of the buffer in the Buffer Size field. The recommended buffer size is 32 KB. The buffer maintains information on a first-in, first-out basis. If the buffer is full and you click Show Buffer, the most recent data is always displayed. |
File Logging | Maintain a log file on an external server or in Flash memory. If the switch fails, it writes information about the cause of the failure to this file before functionality is lost. Click Help for instructions on how to configure this parameter. |
Syslog | Use the UNIX syslog facility to manipulate log information written to a UNIX host. Log information sent to the UNIX host is then managed according to the facility. Click Help for instructions on how to configure this parameter. |
The switch can log eight levels of messages. When you select a logging level, the switch logs all syslog messages of that level and above. The default level is "Errors." In all cases, the severity level defines the amount of detail to be logged.
Select a level from one of the following choices on the Logging Level drop-down list:
Emergencies | The switch is at risk of failing. |
Alert | A condition exists that should be corrected immediately. |
Critical | A critical condition exists, such as a device error. |
Errors | Errors. |
Warnings | Warning messages. |
Notifications | Conditions that are not errors, but that could require special handling. |
Information | Informational messages. |
Debugging | Messages only used for debugging. |
Posted: Thu Apr 13 12:59:40 PDT 2000
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