|
|
This feature module describes the Frame Relay ELMI Address Registration feature and includes information about benefits, supported platforms, related documents, and more.
This document includes the following sections:
The Frame Relay ELMI Address Registration feature enables a network management system (NMS) to detect connectivity among the switches and routers in a network using the Enhanced Local Management Interface (ELMI) protocol. During ELMI version negotiation, neighboring devices exchange their management IP addresses and ifIndex. The NMS polls the devices to collect this connectivity information.
Before this feature was introduced, NMS could detect only the topology of routers or the topology of switches. The NMS could not detect router and switch interconnection and was therefore unable to create a complete topology of the network. With the Frame Relay ELMI Address Registration feature, the NMS can detect switch and router interconnection and create an end-to-end network topology map for network administrators.
Figure 1 shows a typical network in which ELMI address registration is in use.
The Cisco Frame Relay MIB has been enhanced to support the new ELMI information. The NMS uses the MIB to extract the IP address and ifIndex of devices neighboring the managed device.
 |
Note The ELMI address registration mechanism does not check for duplicate or illegal addresses. |
ELMI address registration takes place on all interfaces on which ELMI is enabled, even if all the interfaces are connected to the same router or switch. The router periodically sends a version inquiry message with version information, the management IP address, and ifIndex to the switch. The switch sends its management IP address and ifIndex using the version status message. When the management IP address of the switch changes, an asynchronous ELMI version status message is sent to the neighboring device immediately.
When ELMI is enabled, the router automatically chooses the IP address of one of the interfaces to use for ELMI address registration purposes. The router will choose the IP address of an Ethernet interface first, and then serial and other interfaces. You have the option to use the IP address chosen by the router or to disable the autoaddress mechanism and configure the management IP address yourself. You can also choose to disable ELMI address registration on a specific interface or on all interfaces.
The Frame Relay ELMI Address Registration feature provides an end-to-end networking solution with integrated network management capability. Using the ELMI protocol and an enhanced MIB, an NMS can now detect connectivity among the switches and routers in a network. This new functionality allows for autodetection of the complete network topology.
The following restrictions apply to the Frame Relay ELMI Address Registration feature:
Standards
No new or modified standards are supported by this feature.
MIBs
Cisco Frame Relay MIB
For descriptions of supported MIBs and how to use MIBs, see the Cisco MIB web site on Cisco Connection Online (CCO) at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
RFCs
No new or modified RFCs are supported by this feature.
ELMI must be enabled on the Cisco router and the Cisco switch.
See the following sections for configuration tasks for the Frame Relay ELMI Address Registration feature. Each task in the list is identified as optional or required.
To configure the IP address for ELMI address registration, use the following global configuration command:
| Command | Purpose |
|---|---|
Router(config)#frame-relay address registration ip address | Configures the IP address to be used for ELMI address registration. |
To disable the automatic selection of the IP address to be used for ELMI address registration, use the following global configuration command:
| Command | Purpose |
|---|---|
Router(config)#no frame-relay address registration auto-address | Disables the automatic selection of the IP address to be used for ELMI address registration. |
|
Note Automatic IP address selection is also disabled when you configure the management IP address using the frame-relay address registration ip global configuration command. |
To disable ELMI address registration on an interface, use the following interface configuration command:
| Command | Purpose |
|---|---|
Router(config-if)#no frame-relay address-reg enable | Disables ELMI address registration on an interface. |
To verify that ELMI address registration is configured correctly, use the following privileged EXEC configuration command:
| Command | Purpose |
|---|---|
Router#show frame-relay qos-autosense [interface interface] | Displays the QoS1 values sensed from the switch. |
To monitor ELMI address registration, use one or more of the following privileged EXEC commands:
| Command | Purpose |
|---|---|
Router#show frame-relay qos-autosense [interface interface] | Displays the QoS values sensed from the switch. |
Router#debug frame-relay lmi [interface interface] | Displays information about the LMI1 packets exchanged by the router and the Frame Relay service provider. |
This section provides the following configuration examples:
The following example shows how to configure the IP address to be used for ELMI address registration. Automatic IP address selection is automatically disabled when the IP address is configured. ELMI is enabled on serial interface 0.
interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense ! frame-relay address registration ip address 139.85.242.195 !
The following example shows how to disable the automatic IP address selection mechanism. ELMI is enabled on serial interface 0. Because no other IP address was configured, the router will share an IP address of 0.0.0.0 and a valid ifIndex.
interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense ! no frame-relay address registration auto !
In the following example, ELMI address registration is disabled on serial interface 0. This interface will share an IP address of 0.0.0.0 and an ifIndex of 0. Automatic IP address selection is enabled by default, so the management IP address of other interfaces on this router will be chosen automatically.
interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense no frame-relay address-reg-enable !
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.
To enable a router to automatically select a management IP address for ELMI address registration, use the frame-relay address registration auto-address global configuration command. To disable automatic address selection, use the no form of this command.
frame-relay address registration auto-addressSyntax Description
This command has no arguments or keywords.
Defaults
Auto address selection is enabled.
Command Modes
Global configuration
Command History
12.1(3)T This command was introduced.
Release
Modification
Usage Guidelines
During system initialization, if no management IP address is configured, then the router automatically selects the IP address of one of the interfaces. The router will choose an Ethernet interface first and then serial and other interfaces. If you do not want the router to select a management IP address during system initialization, the no form of this command can be stored in the configuration.
When automatic address selection is disabled and an IP address has not been configured using the frame-relay address registration ip global configuration command, the IP address for ELMI address registration will be set to 0.0.0.0.
The no frame-relay address registration ip command will set the IP address to 0.0.0.0, even when Frame Relay automatic address selection is enabled.
If you configure the IP address using the frame-relay address registration ip global configuration command, the IP address you configure will overwrite the IP address chosen automatically by the router.
If you enable automatic address selection after configuring the IP address using the frame-relay address registration ip global configuration command, the IP address chosen automatically by the router will overwrite the IP address you originally configured.
Examples
The following example shows ELMI enabled on serial interface 0. The automatic IP address selection mechanism is disabled, and no other management IP address has been configured, so the device will share a valid ifIndex and a management IP address of 0.0.0.0.
! interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense ! no frame-relay address registration auto-address ! !
Related Commands
frame-relay address-reg enable Enables ELMI address registration on an interface. frame-relay address registration ip Configures the IP address to be used for ELMI address registration. frame-relay qos-autosense Enables ELMI on the Cisco router.
Command
Description
To configure the IP address for ELMI address registration, use the frame-relay address registration ip global configuration command. To set the IP address to 0.0.0.0, use the no form of this command.
frame-relay address registration ip address
Syntax Description
address IP address to be used for ELMI address registration.
Defaults
No default behavior or values.
Command Modes
Global configuration
Command History
12.1(3)T This command was introduced.
Release
Modification
Usage Guidelines
A management IP address configured by using the frame-relay address registration ip command will overwrite the IP address chosen by the router when automatic address selection is enabled.
The no frame-relay address registration ip command will disable automatic IP address selection and set the management IP address to 0.0.0.0.
If you enable automatic address selection with the frame-relay address registration auto-address global command after configuring the IP address using the frame-relay address registration ip global configuration command, the IP address chosen automatically by the router will overwrite the IP address you originally configured.
Examples
The following example shows ELMI enabled on serial interface 0. The IP address to be used for ELMI address registration is configured, so automatic IP address selection is disabled by default.
! interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense ! frame-relay address registration ip address 139.85.242.195 !
Related Commands
frame-relay address reg-enable Enables ELMI address registration on an interface. frame-relay address registration auto-address Enables a router to automatically select the IP address to be used for ELMI address registration. frame-relay qos-autosense Enables ELMI on a Cisco router.
Command
Description
To enable ELMI address registration on an interface, use the frame-relay address-reg enable interface configuration command. To disable ELMI address registration, use the no form of this command.
frame-relay address-reg enableSyntax Description
This command has no arguments or keywords.
Defaults
ELMI address registration is enabled.
Command Modes
Interface configuration
Command History
12.1(3)T This command was introduced.
Release
Modification
Usage Guidelines
ELMI address registration is enabled by default when ELMI is enabled.
Examples
The following example shows ELMI address registration disabled on serial interface 0.
interface Serial 0 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay qos-autosense no frame-relay address-reg enable
Related Commands
frame-relay address registration auto-address Enables a router to automatically select the IP address to be used for ELMI address registration. frame-relay address registration ip Configures the IP address to be used for ELMI address registration. frame-relay qos-autosense Enables ELMI on a Cisco router.
Command
Description
To display the QoS values sensed from the switch, use the show frame-relay qos-autosense EXEC command.
show frame-relay qos-autosense [interface number]
Syntax Description
interface number (Optional) Indicates the number of the physical interface for which you want to display QoS information.
Defaults
No default behavior or values.
Command Modes
EXEC
Command History
11.2 This command was introduced. 12.1(3)T This command was modified to display information about ELMI address registration.
Release
Modification
Examples
The following is sample output from the show frame-relay qos-autosense command when ELMI and ELMI address registration are enabled.
Router# show frame-relay qos-autosense ELMI information for interface Serial1 IP Address used for Address Registration:9.2.7.9 My Ifindex:4 ELMI AR status : Enabled. Connected to switch:hgw1 Platform:2611 Vendor:cisco Sw side ELMI AR status: Enabled IP Address used by switch for address registration :9.2.6.9 Ifindex:5 ELMI AR status : Enabled. (Time elapsed since last update 00:00:40)
The following is sample output from the show frame-relay qos-autosense command when ELMI is enabled:
Router# show frame-relay qos-autosense
ELMI information for interface Serial1
Connected to switch:FRSM-4T1 Platform:AXIS Vendor:cisco
(Time elapsed since last update 00:00:30)
DLCI = 100
OUT: CIR 64000 BC 50000 BE 25000 FMIF 4497
IN: CIR 32000 BC 25000 BE 12500 FMIF 4497
Priority 0 (Time elapsed since last update 00:00:12)
DLCI = 200
OUT: CIR 128000 BC 50000 BE 5100 FMIF 4497
IN: CIR Unknown BC Unknown BE Unknown FMIF 4497
Priority 0 (Time elapsed since last update 00:00:13)
Table 1 describes the significant fields in the output display.
| Field | Description |
|---|---|
IP Address used for Address Registration | Management IP address of the DTE1 interface. |
My ifIndex | ifIndex of the DTE interface on which ELMI is running. |
ELMI AR status | Indicates whether ELMI is enabled or disabled on the interface. |
Connected to switch | Name of neighboring switch. |
Platform | Platform information about neighboring switch. |
Vendor | Vendor information about neighboring switch. |
Sw side ELMI AR status | Indicates whether ELMI is enabled or disabled on the neighboring switch. |
IP Address used by switch for address registration | IP address of DCE. If ELMI is not supported or is disabled, this value will be 0.0.0.0. |
ifIndex | ifIndex of DCE. |
DLCI | Value that indicates which PVC statistics are being reported. |
Out: | Values reporting settings configured for the outgoing Committed Information Rate, Burst Size, Excess Burst Size, and FMIF. |
In: | Values reporting settings configured for the incoming Committed Information Rate, Burst Size, Excess Burst Size, and FMIF. |
Priority | Value indicating priority level (currently not used). |
Related Commands
frame-relay qos-autosense Enables ELMI on the Cisco router. show frame-relay pvc Displays statistics about PVCs for Frame Relay interfaces.
Command
Description
This section documents the modified debug command related to the Frame Relay ELMI Address Registration feature.
Use the debug frame-relay lmi privileged EXEC command to display information on the local management interface (LMI) packets exchanged by the router and the Frame Relay service provider. To disable debugging output, use the no form of this command to disable debugging output.
debug frame-relay lmi [interface name]
Syntax Description
interface name (Optional) Name of interface.
Defaults
No default behavior or values.
Command History
12.1(3)T This command was modified to display information about ELMI address registration.
Release
Modification
Usage Guidelines
You can use this command to determine whether the router and the Frame Relay switch are sending and receiving LMI packets properly.
|
Note Because the debug frame-relay lmi command does not generate much output, you can use it at any time, even during periods of heavy traffic, without adversely affecting other users on the system. |
Examples
LMI Exchange Example
The following is sample output from the debug frame-relay lmi command:
The first four lines describe an LMI exchange. The first line describes the LMI request that the router has sent to the switch. The second line describes the LMI reply that the router has received from the switch. The third and fourth lines describe the response to this request from the switch. This LMI exchange is followed by two similar LMI exchanges. The last six lines consist of a full LMI status message that includes a description of the two permanent virtual circuits (PVCs) of the router.
Table 2 describes significant fields of the debug frame-relay lmi output.
| Field | Description |
|---|---|
Serial1(out) | Indicates that the LMI request was sent out on the Serial1 interface. |
StEnq | Command mode of message: StEnq—Status inquiry Status—Status reply |
clock 20212760 | System clock (in milliseconds). Useful for determining whether an appropriate amount of time has transpired between events. |
myseq 206 | Myseq counter maps to the CURRENT SEQ counter of the router. |
yourseen 136 | Yourseen counter maps to the LAST RCVD SEQ counter of the switch. |
DTE up | Line protocol up/down state for the DTE (user) port. |
RT IE 1 | Value of the report type information element. |
length 1 | Length of the report type information element (in bytes). |
type 1 | Report type in RT IE. |
KA IE 3 | Value of the keepalive information element. |
length 2 | Length of the keepalive information element (in bytes). |
yourseq 138 | Yourseq counter maps to the CURRENT SEQ counter of the switch. |
PVC IE 0x7 | Value of the permanent virtual circuit information element type. |
length 0x6 | Length of the PVC IE (in bytes). |
dlci 401 | |
status 0 | Status value. Possible values include the following:
|
bw 56000 |
ELMI Address Registration Example
The following is sample output from the debug frame-relay lmi command when ELMI address registration is in use and the data terminal equipment (DTE) has sent a version inquiry message to the date circuit-terminating equipment (DCE). The output specific to address registration is indicated in bold type:
elmi3600# debug frame-relay lmi interface hssi 1/0 Frame Relay LMI debugging is on PVC IE 0x7 , length 0x6 , dlci 304, status 0x2 , bw 64000 ELMI:sending version status_enquiry message datagramstart = 0x7D991D4, datagramsize = 73 FR encap = 0x00010308 00 75 95 01 01 08 09 3D 0A 63 69 73 63 6F 20 20 20 20 20 20 20 20 20 20 33 36 34 30 20 20 20 20 20 20 20 20 20 20 20 33 36 34 30 20 20 20 20 20 20 20 20 20 20 20 01 00 00 00 04 09 02 07 09 00 00 00 00 00 80
Table 3 describes the fields relevant to ELMI address registration when the DTE sends a version inquiry message to the DCE.
| Field | Description |
|---|---|
01 | Indicates that ELMI address registration is enabled. Possible values include:
|
00 00 00 04 | ifIndex of the DTE interface on which ELMI is running. |
09 02 07 09 | Management IP address of the DTE. |
The following is sample output from the debug frame-relay lmi command when ELMI address registration is in use and the DCE has sent a version status message response to the DTE. The output specific to address registration is indicated in bold type:
Hssi1/0(in): Status, myseq 1 RT IE 1, length 1, type 8 ELMI: packet received on Hssi1/0 datagramstart = 0x3600854, datagramsize = 72 FR encap = 0xFCF10309 00 7D 95 01 01 08 09 3D 0A 63 69 73 63 6F 20 20 20 20 20 20 20 20 20 20 32 36 31 31 20 20 20 20 20 20 20 20 20 20 20 68 67 77 31 20 20 20 20 20 20 20 20 20 20 20 01 00 00 00 01 01 02 03 04 00 00 00 00 00 80 ELMI: received version status, version type = Enhanced cisco 2611 hgw1 1 1.2.3.4
Table 4 describes the fields relevant to ELMI address registration when the DCE sends a version status message to the DTE.
| Field | Description |
|---|---|
01 | Indicates that ELMI address registration is enabled. Possible values include:
|
00 00 00 01 | ifIndex of the DCE interface. |
01 02 03 04 | Management IP address of the DCE. |
Posted: Tue Sep 19 17:37:25 PDT 2000
Copyright 1989-2000©Cisco Systems Inc.