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Table Of Contents
Managing Physical and Logical Network Services with Topology Services
Starting and Navigating in Topology Services
Using the Topology Services Main Window
Inter-Switch Link (ISL) Protocol
Differences Between Traditional and Virtual LANs (VLANs)
LAN Emulation (LANE) Configuration
ATM LANE Configuration Guidelines
Troubleshooting Topology Services
Can VLANs in a VTP server domain have the same name as a VLAN on a VTP transparent switch?
Can you move ports from a transparent switch into a VLAN in the parent VTP domain?
Will Topology Services display VLAN information for a switch that is in VTP transparent mode?
Why is there is no information about the LE Config Server in the summary of an ATM-VLAN?
Why does a Windows NT server appear as an application server?
Managing Physical and Logical Network Services with Topology Services
Topology Services is an application that enables you to view, monitor, and configure the physical and logical services on your network:
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View detailed network information about all devices, links, and ports in your network.
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The following topics give an overview of Topology Services. For more detailed information, refer to the Topology Services online help.
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Starting and Navigating in Topology Services
From the CiscoWorks2000 desktop, select Campus Manager > Topology Services. The Topology Services main window appears.
Topology Services provides multiple windows for performing tasks. Refer to the following sections for a description of the elements in the windows:
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Using the Topology Services Main Window
The Topology Services main window displays VTP domains, VLANs, ATM domains, and ATM-VLANs discovered in your network. The main window is divided into five components: Menu Bar, Tool Bar, Tree View, Summary View, and Status Bar (see Figure 2-1).
Figure 2-1 Topology Services Main Window
Topology Services provides several methods for accessing network information or status, as shown in Table 2-1.
Table 2-1 Topology Services Main Window Components
Menu Bar
Contains Topology Services commands.
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Toolbar
Provides quick access to frequently used menu options.
To show or hide the toolbar, select View > Show Toolbar.
Tree View
Displays discovered VTP domains, VLANs, ATM domains, and ATM-VLANs. You can access the LAN Edge, Layer 2, and Unconnected Devices network views of managed domains.
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Summary View
Displays configuration information about the items displayed in the Tree View.
Click and drag column headings to change the order in which they appear.
Status Bar
Displays Topology Services system messages on the left and the Discovery Status button on the right.
Double-clicking on the status light displays the Discovery Information dialog box, which tells you your ANI Server and User Tracking login status and the completion time of the last ANI and User Tracking discoveries.
You can access all network and domain summary information from Topology Services by clicking on the corresponding folder in the tree view of the main Topology Services window:
Managed Domains—Displays the ATM and VTP domain configuration.
Network Views—Displays the following:
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Using Network Topology Views
A network topology view is a graphical representation of the devices in your network. You can use network topology views to see different aspects of your network. Only devices and links discovered in your network are displayed. As you use Topology Services, listed devices and links change dynamically to display what the ANI Server discovers in your network.
Network Topology views provide various abstract views of your network (see Figure 2-2). Table 2-2 describes the Network Topology window components.
Figure 2-2 Network Topology Windows
Using Topology Services
Table 2-3 describes the main tasks you can perform with Topology Services. For more information about each task, refer to Topology Services online help.
Table 2-3 Topology Services Tasks
View summary information.
Displays detailed information about the managed domains in your network.
From the tree view, click on a managed domain or a network view from the tree view. The summary information about the domain appears in the right pane.
Open a network topology view.
Displays a graphical representation of the devices in your network.
You can customize the network views and use Find to find elements in the network views.
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To change the view layout:
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Display Device Labels.
Displays device information labels in network topology views.
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To clear labels, select View > Display Labels > Clear Labels.
Download a Cisco Visio stencil.
Downloads the cm_cisco.vss stencil file. After the stencil is downloaded once, you can export a network topology view to Visio.
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Export a network topology view to Visio.
Exports a network topology view as a text file that can be used in Visio to create a drawing.
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Display Device, Port, Link, Aggregate Link, or Trunk Attributes.
Displays information about devices, ports, links, aggregate links, or trunks on your network.
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Display Service Attributes.
Displays information about the available services in your network.
From a network topology view, right-click an application server icon and select Service Attributes.
Access ICS Devices.
Starts the Cisco ICS System Manager.
From a network topology view, right-click an ICS device icon and select Cisco ICS System Manager.
Access Application Servers and start Cisco CallManager.
Gives access to an applications server.
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Display Multi-Layer Switching (MLS) Reports.
Displays information about devices in your network that participate in multi-layer switching.
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View ANI Server Discovery Metrics.
Displays a report containing statistics for the last n discovery cycles.
From the Topology Services main window, select Reports > Discovery Report.
View Discrepancy Reports.
Displays a report of physical or logical discrepancies on your network.
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Customize Discrepancy Reports.
Allows you to choose which discrepancies you want reported.
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View the Color and Icon Legend.
Displays a legend of icons and colors used in the network views.
Select Help > Legend....
Create an Ethernet VLAN.
Provides a visual method of creating, modifying, and deleting an Ethernet VLAN in your network.
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Create a Token Ring VLAN.
Provides a visual method of creating, modifying, and deleting a Token Ring VLAN in your network.
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View Spanning Tree definitions.
Allows you to view the spanning tree definitions on your network.
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The Network Topology window appears.
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Add a LAN Emulation Server (LES) to an existing VLAN.
Allows you to extend VLANs across ATM networks.
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Configure an LE Config Server (LECS).
Allows you to configure an LE Config Server (LECS) on each ATM domain.
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Create an SPVC or SPVP.
Allows you to create an SPVC or SPVP between two devices.
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Display a Virtual Connection.
Displays information about a virtual connection (VC).
You can focus on particular VC types in your ATM domain, and you can determine the amount of bandwidth used on a link by a VC.
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Perform a Virtual Connection (VC) Trace.
Displays information about your virtual connection (VC) in tabular and graphical formats.
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Set the ATM interface configuration.
Allows you to set the interface configuration on ATM devices, without the CLI.
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Topology Services Concepts
You should understand these concepts when using Topology Services:
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ANI Server
Campus Manager uses the CiscoWorks2000 Server's Asynchronous Network Interface (ANI) Server to automatically discover devices in your network. This service must be set before you can use Campus Manager. Refer to Getting Started with the CiscoWorks2000 Server or the ANI Server online help for details about this service.
Supported Protocols
The following concepts are important for understanding how to use Topology Services:
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You must make sure that the applicable protocols are implemented correctly in your network; otherwise, the information gathered might be incomplete.
Virtual Trunk Protocol (VTP)
To implement VLANs in your network, you must activate Virtual Trunk Protocol (VTP) on all switches that will participate in the VLAN-segmented network. Using VTP, each switch in server mode advertises its management domain on its trunk ports, its configuration revision number, and its known VLANs and their specific parameters. A VTP domain is made up of one or more interconnected devices that share the same VTP domain name. A switch can be configured for only one VTP domain.
VTP servers and clients maintain all VLANs everywhere within the VTP domain. A VTP domain defines the boundary of the specified VLAN. Servers also transmit information through trunks to other attached switches and receive updates from those trunks.
For more information on:
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Spanning-Tree Protocol
Spanning-Tree Protocol is a link management protocol that provides path redundancy while preventing undesirable loops in the network. For an Ethernet network to function properly, only one active path can exist between two stations.
Multiple active paths between stations cause loops in the network. If a loop exists in the network, hosts might receive duplicate messages. In addition, switches might learn host Media Access Control (MAC) addresses on multiple switch ports. These conditions result in an unstable network.
The spanning tree algorithm calculates the best loop-free path throughout a switched network. This is necessary for the creation of fault-tolerant internetworks.
Spanning tree defines a tree with a root switch and a loop-free path from the root to all switches in the extended Layer 2 network. Spanning Tree Protocol (STP) forces redundant data paths into a standby (blocked) state. If a network segment in the spanning tree fails and a redundant path exists, the spanning tree algorithm recalculates the spanning tree topology and activates the standby path.
Inter-Switch Link (ISL) Protocol
Inter-Switch Link (ISL) is a Cisco-proprietary protocol that allows VLAN trunking by maintaining VLAN information as traffic flows between switches and routers.
You can pass VLAN information between devices by configuring links between the switches. If you want a link to carry more than one VLAN, you must use ISL. To use ISL, you must configure the ports on both sides of the link as trunk ports.
When two VTP domains are interconnected using an ISL trunk between two LAN switches, by default, no VLAN traffic is forwarded. However, you can configure the ports on each switch to receive and forward specific VLANs. To configure the ports, the VLANs on either side of the ISL trunk must be identical and share the same VLAN characteristics such as VLAN names, VLAN indexes, and so on.
IEEE 802.1Q
IEEE 802.1Q is the industry-standard encapsulation protocol to carry traffic for multiple VLANs over a single link.
LAN Emulation (LANE)
LANE services are commonly required to provide Ethernet connectivity across ATM backbones. LANE emulates the layer-2 logical services of Ethernet networks across ATM devices, such as the LightStream 1010 ATM switches and the LANE modules in the Catalyst 5000 series switches. Specifically, LANE provides the broadcast and multicast functions of Ethernet networks across these ATM backbones.
For more information on LANE, refer to the "LAN Emulation (LANE) Configuration" section.
Token Ring Bridging Protocols
Two Token Ring bridging protocols are supported:
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If the trCRF is configured for SRB, ports configured in the trCRF are members of the broadcast domain for the non-source route (NSR) broadcast issued by stations seeking their designation station. Stations belonging to a different trCRF do not receive these broadcasts.
When the NSR broadcast fails to find the destination station, the station sends an All Routes Explorer (ARE) frame. The ARE propagates to all trCRFs belonging to the trBRF. This broadcast frame is not propagated to trCRFs belonging to other trBRFs unless there is an external connection between the trBRFs.
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If the trCRF is configured for SRT, non-source route (NSR) broadcasts are forwarded to other trCRFs (within the same parent trBRF). The trBRF transparently bridges these NSR broadcasts to other trCRFs configured for SRT. All NSR- and NSR-configured trCRF children view the trBRF as a traditional transparent bridge.
Refer to the "Token Ring VLANs" section for information about Token Ring VLANs.
Virtual LANs (VLANs)
A Virtual LAN (VLAN) is a group of devices on one or more LANs on different network segments that are configured so they can communicate as if they were all on the same network segment. VLANs are based on logical connections instead of physical connections, so they are extremely flexible.
VLANs allow you to group ports on a switch to limit unicast, multicast, and broadcast traffic flooding. Flooded traffic originating from a particular VLAN is only flooded out other ports belonging to that VLAN.
The following topics provide you with information about:
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Differences Between Traditional and Virtual LANs (VLANs)
A traditional LAN is configured according to the physical infrastructure it is connecting. Users are grouped based on their location in relation to the hub they are connected to and how the cable is run to the wiring closet. Segmentation is typically provided by the routers that connect each shared hub.
A virtual LAN (VLAN) is a switched network that is logically segmented by functions, project teams, or applications regardless of the physical location of users. Each switch port can be assigned to a different VLAN. Ports in a VLAN share broadcasts; ports that do not belong to that VLAN do not share these broadcasts.
Switches remove the physical constraints imposed by a shared-hub architecture because they logically group users and ports across the enterprise. As a replacement for shared hubs, switches remove the physical barriers imposed in each wiring closet.
Advantages of VLANs
VLANs provide the following advantages:
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Simplification of Moves, Adds, and Changes
Adds, moves, and changes are some of the greatest expenses in managing a network. Many moves require recabling and almost all moves require new station addressing and hub and router reconfiguration.
VLANs simplify adds, moves, and changes. VLAN users can share the same network address space regardless of their location. If a group of VLAN users move but remain in the same VLAN connected to a switch port, their network addresses do not change. If a user moves from one location to another but stays in the same VLAN, the router configuration does not need to be modified.
Controlled Broadcast Activity
Broadcast traffic occurs in every network. If incorrectly managed, broadcasts can seriously degrade network performance or even bring down an entire network. Broadcast traffic in one VLAN is not transmitted outside that VLAN, which substantially reduces overall broadcast traffic, frees bandwidth for real user traffic, and lowers the vulnerability of the network to broadcast storms.
You can control the size of broadcast domains by regulating the size of their associated VLANs and by restricting both the number of switch ports in a VLAN and the number of people using these ports.
You can also assign VLANs based on the application type and the amount of application broadcasts. You can place users sharing a broadcast-intensive application in the same VLAN group and distribute the application across the campus.
Workgroup and Network Security
You can use VLANs to provide security firewalls, restrict individual user access, flag any unwanted network intrusion, and control the size and composition of the broadcast domain.
You can increase security by segmenting the network into distinct broadcast groups. VLANs provide the following advantages:
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VLAN Components
VLAN components are:
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Switches are the entry point for end-station devices into the switched domain and provide the intelligence to group users, ports, or logical addresses into common communities of interest. LAN switches also increase performance and dedicated bandwidth across the network.
You can group ports and users into communities using a single switch or connected switches. By grouping ports and users across multiple switches, VLANs can span single-building infrastructures, interconnected buildings, or campus networks. Each switch can make filtering and forwarding decisions by packet and communicate this information to other switches and routers within the network.
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Routers provide policy-based control, broadcast management, and route processing and distribution. They also provide the communication between VLANs and VLAN access to shared resources such as servers and hosts. Routers connect to other parts of the network that are either logically segmented into subnets or require access to remote sites across wide area links.
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The VLAN transport enables information exchange between interconnected switches and routers on the corporate backbone. The backbone acts as the aggregation point for large volumes of traffic. It also carries end-user VLAN information and identification between switches, routers, and directly attached servers. Within the backbone, high-bandwidth, high-capacity links carry the traffic throughout the enterprise.
Types of VLANs Supported
Topology Services supports four types of VLANs:
Ethernet VLANs
An Ethernet VLAN is the typical VLAN design, which consists of a logical group of end-stations, independent of physical location on an Ethernet network. Catalyst switches support a port-centric, or static, VLAN configuration. All end stations connected to ports belonging to the same VLAN are assigned to the same Ethernet VLAN.
ATM-VLANs
An ATM-VLAN spans an ATM network bridging two or more Ethernet VLANs using LAN Emulation (LANE). LANE provides connectivity between ATM-attached devices by emulating a LAN over an ATM cloud, including the following:
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Because LANE connectivity is defined at the MAC layer, upper protocol layer functions of LAN applications can continue unchanged when the devices join ATM-VLANs.
An ATM network can support multiple independent ATM-VLANs. End-system membership in any of the ATM-VLANs is independent of the physical location of the end system, which simplifies hardware moves and changes. In addition, end-stations can move easily from one ATM-VLAN to another, whether or not the hardware moves.
Figure 2-3 ATM LANE to Extend VLANs Example
Token Ring VLANs
A Token Ring VLAN is a set of rings interconnected through a bridging function. You must use VTP version 2 to deploy Token Ring VLANs using Campus Manager.
Two Token Ring VLAN types are defined in VTP version 2:
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Figure 2-4 Token Ring VLANs
LAN Emulation (LANE) Configuration
LAN Emulation (LANE) enables existing applications to access an ATM network as if they were operating over traditional LANs, such as Ethernet or Token Ring. LANE allows LAN users to benefit from ATM without modifying end-system hardware or software. End-user hosts on LANs can connect to other end-user hosts on LANs, as well as to ATM-attached servers, routers, and switches.
LANE reconciles the differences between ATM and LAN protocols by masking the connection setup and handshaking functions required by the ATM switch. LANE basically bridges LAN traffic across ATM. LANE has specific hardware requirements. For details, refer to your switch or router documentation.
The following topics provide you with information about:
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LANE Components
LANE is defined on a client-server LAN model, and the following LANE components must be configured for LANE services to be fully functional:
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These LANE components and the requirements for using them in an ATM network are described in Table 2-4.
Table 2-4 LANE Component Descriptions
LE Configuration Server (LECS)
Contains the database that determines to which master LECS an ATM-VLAN client belongs. Clients consult the LE configuration server to determine which ATM-VLAN it should join. The LECS returns the ATM address of the LES for that ATM-VLAN, and also maintains the LES redundancy information.
Cisco recommends having one master LECS per ATM domain. Campus Manager does not support more than one master LECS, but you can have additional backup LECSs.
Broadcast Server1 (BUS)
Sequences and distributes multicast and broadcast packets and handles unicast flooding.
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Cisco recommends having one active master combined LE/Broadcast server per ATM-VLAN. You can have additional backup LE/Broadcast servers.
LE Server (LES)1
The LE server acts as the control center. Provides joining, address resolution, and address registration services to the LE clients in that ATM-VLAN. Clients can register destination unicast and multicast MAC addresses with the LE server. The LE server also handles LANE Address Resolution Protocol (LE_ARP) requests and responses.
Clients can communicate directly with one another only when they are connected to the same LE server.
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Cisco recommends having one active master combined LE/Broadcast server per ATM-VLAN. Multiple LE/Broadcast servers can exist on the same physical ATM network where each server supports a different ATM-VLAN. You can have additional backup LE/Broadcast servers.
LE Client (LEC)
The LE Client emulates a LAN interface to higher-layer protocols and applications. It forwards data to other LANE clients and performs LANE address-resolution functions.
Can be a member of only one ATM-VLAN.
An ATM device can have several LE clients—one client for each ATM-VLAN of which it is a member.
1 In Cisco's implementation of LANE, the LE server and broadcast server are one entity. In this document, references to an LE server include the broadcast server.
How LANE Works
ATM is a connection-oriented service, while LAN is a broadcast medium. ATM uses connection-oriented service with point-to-point signaling or multipoint signaling between source and destination devices. LAN-based protocol suites use connectionless service and broadcasts to enable source devices to find one or more destination devices.
Using LANE, LAN broadcasts are emulated as ATM unicasts. LANE emulates a broadcast environment such as IEEE 802.3 Ethernet or 802.5 Token Ring on top of an ATM network that is a point-to-point environment. Client devices, such as routers, ATM workstations, and LAN switches use LES functions to emulate a LAN across ATM.
LANE defines a service interface for network layer protocols that is identical to existing MAC layers. No changes are required to existing upper layer protocols and applications. Data sent across the ATM network is encapsulated in the appropriate LAN MAC packets. LANE essentially bridges LAN traffic across ATM and defines the operation of an emulated LAN.
LANE does not emulate every particular physical or data-link characteristic. For example, it does not support carrier sense multiple access collision detect (CSMA/CD) for either Ethernet or Token Ring. LANE on the ATM switch router supports only the IP protocol.
LANE can be implemented on these devices:
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Communication among LANE components is ordinarily handled by several types of switched virtual channel circuits (VCCs). Some VCCs are unidirectional; others are bidirectional. Some are point-to-point; others are point-to-multipoint. (See Figure 2-5.)
Figure 2-5 LANE Virtual Circuit Types
The elements in Figure 2-5 function as follows:
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ATM LANE Configuration Guidelines
Use these guidelines when configuring LANE:
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In the event of an ATM network failure, there can be multiple master LECs and multiple active LES/BUSs for the same ELAN, resulting in a partitioned network. Clients continue to operate normally, but transmission between different partitions of the network is not possible. The system recovers when the network break is repaired.
VTP Domains
Before using Topology Services to monitor the VLANs in your network, consider your VTP domain design.
A VTP domain is made up of one or more interconnected devices that share the same VTP domain name. A switch can be configured to be in only one VTP domain, and each VLAN has a name that is unique within a management domain.
Typically, you use a VTP domain to ease administrative control of your network or to account for physical boundaries within your network. However, you can set up as many or as few VTP domains as are appropriate for your administrative needs. Consider that VTP is transmitted on all trunk connections, including ISL, IEEE 802.1Q, 802.10, and LANE.
The following topics provide you with information about:
Virtual Trunk Protocol (VTP)
Using Virtual Trunk Protocol (VTP), each switch in server mode advertises its management domain on its trunk ports, its configuration revision number, and its known VLANs and their specific parameters. Therefore, a new VLAN must be configured on only one device in the management domain, and the information is automatically learned by all the other devices (not in VTP transparent mode) in the same management domain. Once a device learns about a VLAN, it receives all frames on that VLAN from any trunk port and, if appropriate, forwards them to each of its other trunk ports.
Two versions of VTP are supported—VTP 1 and VTP 2. Every switch in the VTP domain must use the same VTP version. The VTP version is important if you use Campus Manager in a Token Ring environment because you must use version 2 with Token Ring devices. Verify the software image version of all of the devices in your network to make sure they support VTP 2.
Components of VTP Domains
Within a VTP domain, you can configure switches as follows:
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Your VTP domain structure influences the behavior of Topology Services. Use these guidelines to ensure that your network is set up correctly for Topology Services:
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One VTP Server—Multiple VTP Clients
In this scenario, at least one VTP server for each VTP domain is required. Cisco recommends that you configure the other devices as VTP clients, especially if you have a large network. Having only one VTP server maintains VLAN consistency across the network.
Multiple VTP Servers
For multiple VTP servers, consider that the device with the most recent configuration revision number controls VTP advertisements. The configuration revision number associated with a device's known set of VLANs (in one management domain). This revision number can be compared to another device's configuration revision number (for the same management domain) to determine which is more recent. This revision number is incriminated when a device is reconfigured to define a new VLAN, delete an existing VLAN, suspend or resume an existing VLAN, or modify the parameters of an existing VLAN.
If a network has two or more VTP servers that are not connected by Inter-Switch Link (ISL), the VLAN configuration on those servers may not be synchronized. In this case, Topology Services reads the VLAN information from the VTP server with the latest revision number. You must ensure that the most recent changes to VLANs are made on the VTP server with the highest configuration revision number.
VTP Server—VTP Transparent
To prevent your devices from participating in VTP, configure them as VTP transparent. When you create a VLAN on a VTP transparent switch, the VLAN is local to that switch, and is not known to other devices in the network.
Topology Services reads VLAN information from the VTP servers and transparent switches in your network. Topology Services attempts to correlate VLAN information between transparent switches and those known to the VTP Server. If a transparent switch is participating in a VLAN identical to the VLAN known to the VTP Server, the VLAN is shown belonging to each.
Provided that you have at least one VTP server in your network, you can create local VLANs on transparent switches. However, you lose a verifiable consolidated view of the VLAN states of your switches. A switch in transparent mode does not communicate its VLAN state to a server nor does it accept changes to its VLAN state from the server.
VTP Not Transparent Only
Even if you use Topology Services in a VTP domain that contains VTP transparent switches and no VTP servers, Topology Services will discover the VLANs in your network. You are not required to have a VTP Server in each VTP domain for Topology Services to discover VLANs.
ATM Domains
You can view and monitor ATM domain status, including standalone ELANs, in your network. You can also use the ATM Domain network views to obtain detail about devices in each ATM domain.
The ANI Server discovers the ATM switches and end hosts, and all physical and logical links among those switches and hosts. These components comprise the ATM domain.
An ATM domain is a group of interconnected ATM switches and ATM end-hosts that can be discovered with the Interim Local Management Interface (ILMI) neighbor discovery mechanism. Switches within the ATM network must support AToM MIB (RFC 1695).
ATM End host contains an ATM network interface adapter. Examples of ATM endpoints are workstations, routers, data service units (DSUs), LAN switches, and video coder-decoder (CODEC).
ATM switches:
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ICS Devices
Integrated Communication System (ICS) devices provide a complete voice and data network solution. They have all the elements needed to deliver data, voice, and video in a single chassis. Refer to the documentation included with the ICS device for more information.
ICS device components are discovered as separate IP addresses, but are shown as one device icon in the network topology view.
See Table 2-3 on how to access an ICS device from Topology Services.
Application Servers
Application servers are high-availability workflow systems that provide categories of service on a network, such as Cisco AVVID (architecture for Voice, Video and Integrated Data) services. For example, a Media Convergence Server (MCS) is an application server providing such AVVID-related applications as Cisco CallManager.
Cisco CallManager provides signaling and call control services to Cisco integrated multimedia applications as well as third-party applications. Cisco CallManager services can be distributed and clustered over an IP network, thereby allowing scale to 10,000 users and triple call-processing redundancy. The ANI Server component of CiscoWorks2000 discovers application servers and Topology Services displays them in the Layer 2 View.
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Troubleshooting Topology Services
Use the information in the following topics to help you troubleshoot Topology Services:
Frequently Asked Questions
Use the information in these sections to answer some of your common questions:
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Does VTP need to be enabled?
Topology Services requires Virtual Trunk Protocol (VTP) to be enabled in order to create VLANs. For most predictable results, Cisco recommends having at least one switch configured as a VTP server and the remaining switches configured as VTP clients.
If there are multiple VTP servers in a VTP domain, which VTP server receives VLAN configuration changes?
If the two VTP servers are in the same domain and are connected by VTP trunks, it does not matter which switch the changes are made on. VTP ensures that the information on all VTP servers and clients in a single VTP domain are coordinated and share the same configuration.
If the servers are in different VTP domains, then they do not share VLAN states, but they are both known to Topology Services. You must select the VTP domain in which you want to make the VLAN changes, and the corresponding VTP servers will reflect those changes.
If there are two servers with the same VTP domain that are not connected by trunks the configurations managed by the two servers may diverge. This configuration is not supported by Topology Services, and is reported as a discrepancy.
Can VLANs in a VTP server domain have the same name as a VLAN on a VTP transparent switch?
You can have VLANs with the same name provided that other characteristics, such as VLAN index and SAID value, are also identical. Discrepancies occur when there are identically named VLANs with other attributes that are different (such as index, and so on). Topology Services does not consider it a discrepancy if two VLANs share identical definitions.
It is usually best to use the default names that Topology Services creates for each VLAN.
Can you move ports from a transparent switch into a VLAN in the parent VTP domain?
Yes, but you must first create the VLAN (with identical attributes) on the transparent switch. To create a VLAN that exists on both the VTP server and all the transparent switches in a VTP domain, you can select the Create VLAN on all Transparent Switches check box when creating the VLAN.
Will Topology Services display VLAN information for a switch that is in VTP transparent mode?
Topology Services will attempt to correlate information from VTP transparent switches with VTP servers in the same domain. It will check the ISL index, VLAN name, and VLAN type for each VLAN, if the VLANs are identical, then they will be displayed
In the LAN edge network view, how can I tell which switches in a switch cloud are connected to a router?
The Aggregate Link Attributes option is available when you right-click on a link in the LAN Edge network view. The Aggregate Link Attributes window shows the list of links between a switch cloud and a router. This cannot be indicated in the view itself because individual links are not shown, there can be more than one link between a router and the devices in a switch cloud.
Why is there is no information about the LE Config Server in the summary of an ATM-VLAN?
LE Config Servers do not belong to a specific ATM-VLAN. Different LANE components could be going to different LE Config Servers (based on neighboring LS1010 registry information) to join the same ATM-VLAN.
Why does a Windows NT server appear as an application server?
If a Windows NT server is used as a seed device for ANI Server discovery, it will appear in Topology Services as an application server. Because an application server is installed on Windows NT, Topology Services discovers both of these device types as one device.
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Troubleshooting Suggestions
Use the information in the Troubleshooting Topology Services table to troubleshoot the Topology Services application.
