|
|
| Command | Description |
|---|---|
show interface |
Displays information about a line card interface. |
Cisco Remote Connection Management uses Cisco IOS software commands to configure the local (near-end) digital signal level 3 (DS3) port to match the configuration settings on a remote (far-end) DS3 port to achieve network connectivity and pass data traffic.
Cisco Remote Connection Management (CRCM) is supported on line cards that transmit to DS3 ports. For example, CRCM is supported on the following two types of line cards:
Both line cards are compatible with any Cisco 12000 series router that operates with the Cisco IOS Release 11.2(18)GS4 or a later 11.2(18)GS4 release.
Both line cards support third-party data service unit (DSU) vendors, Digital-Link, Kentrox, and Larscom. The DSU vendors enable connections between a local line card that is installed in a GSR and a remote DS3 port.
Cisco Remote Connection Management is useful because you can independently configure each local line card interface or serial port interface to achieve network connectivity.
Note The examples in this publication refer to the 6DS3-SMB or 12DS3-SMB line cards. However, the Channelized OC-12 to DS3 line card also supports the Cisco Remote Connection Management feature.
You can use Cisco Remote Connection Management to:
The following restrictions apply to Cisco Remote Connection Management:
Note You can use Cisco Remote Connection Management only if (1) both ends of the DS3 line are configured for C-bit parity mode, and (2) the FEAC message from the DS3 payload source terminal to the DS3 payload sink terminal is delivered unaltered.
Cisco Remote Connection Management is supported on the following Cisco 12000 series Gigabit Switch Router (GSR) platforms:
Cisco Remote Connection Management works only when you set the DSU bandwidth to subrate, and the local (near-end) port is configured with the default DSU, cisco.
The American National Standards Institute (ANSI) standard TI-107 describes the standard Far-End Alarm and Control (FEAC) codes in the following requests for comments (RFCs):
Note For descriptions of supported MIBs and how to use them, see Cisco's MIB web site on Cisco Connection Online (CCO) at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.
The following sections describe implementation for each line card that supports Cisco Remote Connection Management.
The channelized OC-12 to DS3 line card (OC12-DS3) supports twelve (12) independent DS3 streams multiplexed over a single OC-12 SONET port. The port is labeled Tx on the left and Rx on the right. You can use either one duplex fiber cable or two simplex fiber cables to connect the port to other devices. You can configure and monitor the DS3 streams on a per channel basis.
The line card has one OC-12 port that provides a duplex SC single-mode intermediate-reach SONET connection.
The line card interfaces through an Add/Drop Multiplexer (ADM) and transmits up to 12 channels of DS3 multiplexed over a single 622-Mbps OC-12 port.
The 6DS3-SMB and 12DS3-SMB line cards consist of high-density DS3 service through six T3 or twelve T3 interfaces. A single port consists of one coaxial connector for receiving (Rx) and one coaxial connector for transmitting (Tx). The serial ports on the 6-port line card are numbered 0-5. The serial ports on the 12-port line card are numbered 0-11. A single serial port can be configured independently of other serial ports on the line card.
When the receive (Rx) side of a serial port on the 6DS3-SMB or 12DS3-SMB line card receives data, it starts clock discovery, checks the data or errors, selects a best-fit length buffer for storing the packet, and writes it to a buffer in the Receive Buffer Memory that is partitioned into buffers of varying length.
The buffers are maintained on queues that include:
When a serial port on the 6DS3-SMB or 12DS3-SMB line card transmits (Tx) side received data, it writes to a partitioned buffer in Transmit Buffer Memory. It tries to match the partitioned buffer lengths used for the Receive Buffer Memory to ensure that the "best fit" decision can be re-used when the packet is received from the switch fabric.
The buffers are maintained on queues that include:
To configure a line card interface or serial port, perform the following tasks.
To locate a local (near-end) line card or serial port interface, perform the following configuration tasks, starting in privileged EXEC mode.
This section describes the procedures for configuring a local line card interface or serial port interface. You can configure serial ports in any sequence. Therefore, the IP addresses assigned to each port do not have to be numbered in sequential order. You can also enter other configuration commands and options, depending on your system requirements.
Use the following procedures to configure a line card interface or serial port interface, beginning in privileged EXEC mode.
Use the telnet ip address command to connect the local (near-end) port to the remote (far-end) port using an intervening third-party DSU. Complete the procedure in this section starting in privileged EXEC mode.
| 1. | Use the telnet ip address command to enable communication between the local (near-end) port and the remote (far-end) port |
If you can use telnet to establish a connection with the remote router and send traffic, this indicates that all the local (near-end) port and the remote (far-end) port configuration settings match.
If you can not establish a connection using the telnet command, it indicates that the DSU and other configuration settings do not match between the local (near-end) interface and remote (far-end) interfaces. For example, the local (near-end) port DSU may be set to kentrox, and the remote (far-end) port DSU may be set to the larscom. The following sections explain how to use Cisco Remote Connection Management commands to change the DSU and other configuration settings on the local (near-end) port to match the remote (far-end) port.
The line cards support the concept of subrates, where each channel can be configured to allow full DS3 bandwidth transmission (fullrate) or fractional DS3 bandwidth transmission (subrate). Both ends of a connection must agree on the bandwidth settings to communicate over the DS3 payload path. In cases where they do not agree, Cisco Remote Connection Management allows you to temporarily force the local (near-end) DS3 port to a known state (where the default configuration settings are; cisco DSU, subrate DS3 bandwidth transmission, and no scramble DS3 payload). Then you can review the remote (far-end) DS3 port settings by using a telnet command line interface (CLI) session. Cisco Remote Connection Management supports both initiation of requests for remote (far-end) DS3 channel reset and response to incoming requests for a local (near-end) DS3 channel reset.
The procedures in this section explain how to remove a third-party DSU, and change the local (near-end) configuration settings beginning in privileged EXEC mode.
Note When you change the DS3 subrate parameter value, it changes the local (near-end) line card interface. Other parameter value changes affect individual DS3 serial ports on the 6DS3-SMB or 12DS3-SMB line card.
After you verify the remote (far end) interface settings through a direct connection, use Cisco Remote Connection Management IOS software commands to make additional configuration changes on the local (near-end) interface to match it. Complete the configuration tasks in this section, beginning in privileged EXEC mode:
After you make the additional configuration changes, use telnet to establish a connection and test network connectivity between the local (near-end) interface and the remote (far-end) interface by using the methods in "Test Network Connectivity" section.
To test data traffic in a direct configuration without an intervening DSU between the local (near-end) port and the remote (far-end) DS3 port, you can:
Clocking mode synchronization can affect the success or failure of network connectivity. To troubleshoot network connectivity, check your clock mode configuration according to the line card type. The internal clock source setting transmits using a locally generated clock, while the line clock source setting (loop timing) uses the recovered receive clock.
If the local (near-end) of a connection is in line clocking mode, then the remote (far-end) must be in internal clocking mode, or in the opposite order.
If both the local (near-end) and remote (far-end) line cards are in internal clocking mode, this configuration works, but is not recommended for some line cards, such as Add/Drop Multiplexers (ADMs). In internal clocking mode, each end of the connection receives data at a frequency that is not exactly matched to its own transmit frequency.
Note If both the local (near-end) and remote (far-end) line cards are in line clocking mode, each end (local or remote) recovers a clock-based on what it receives from its remote end and uses that clock to transmit back to the remote end. This configuration creates a big loop with each end trying unsuccessfully to match the clock of the remote end because there is no fixed frequency source in the loop.
Each local (near-end) and remote (far-end) DS3 serial port recovers a clock from the received data using a phase locked loop (PLL). Each PLL tries to track the data it receives to recover a clock. You can connect the two PLLs in a loop because both ends are in line clocking mode. There is no fixed clock frequency in this loop. Having no fixed frequency may actually work if each end agrees on a common clock frequency.
To test the flow of data traffic, enter one of the three loopback paths that the DS3 controller supports:
On the 6DS3-SMB or 12DS3-SMB line card, each loopback path exists for the local (near-end) ports. All loopback configuration on the 6DS3-SMB or 12DS3-SMB line card is done in the QJET, a quad DS3 framer that provides DS3 payload and limited bit error rate test (BERT) functionality.
Figure 1 shows the data flow for three loopback configuration paths, including the default value, no loopback.
To test data traffic, use one of the loopback interface configuration commands shown in Table 2. Perform the configuration task in this section, beginning in privileged EXEC mode.
Note When using loopback network commands, be sure to enter the no keep command to turn keepalives off. Otherwise, the line will keep trying to come up, causing the port to reset, thereby causing a loss of pattern synchronization if BER testing is running. This will lead to an erroneously high BER.
A Bit Error Rate Test (BERT) checks communication between the local and the remote DS3 ports. You can set the local interface to BER test mode while the remaining interfaces continue to transmit and receive normal traffic.
If traffic is not being transmitted or received, create a back-to-back loopback BERT test and send out a predictable stream to ensure that you receive the same data that was transmitted. To determine if the remote interface returns the bert pattern unchanged, the system administrator for the remote router must manually set the remote interface to loopback network line. Then you can enter a bert pattern interface configuration command at specified time intervals on the local interface.
The following example shows the output from a back-to-back loopback BERT test. The router types are a Cisco 12012 series GSR on the local (near-end), and a Cisco 12008 series router on the remote (far-end). Keepalive is disabled, while the loopback network line test runs between both routers. Clock source is set to internal on the local serial port 8, in slot 1 with IP address 10.0.0.2. Clock source is set to line on the remote serial port 5, in slot 1 with IP address 11.0.0.1. A BERT pattern is entered between local serial port 8/1 and remote serial port 5/1:
Table 3 lists DS3-supported BERT patterns. Test intervals range between 1 to 1140 minutes in length. The command examples show how to invoke an ongoing BERT pattern that will run during user-specified intervals. For example, entering the bert pattern 2^23 interval 10 interface configuration command invokes a 2^23 BER test at ten minute intervals. The no bert pattern interface configuration command will terminate an ongoing BER test and return the local and remote interfaces to their default values. You can enter a BER test pattern beginning in privileged EXEC mode.
To insert intentional errors into the BER test stream, use the bert errors no-of-errors interface configuration command, where the no-of-errors default is 1 and the range is 1 to 255, inclusive. Follow the configuration task in this section to insert 5 errors into the current BER test stream that is running the pseudo-random pattern 2^23 that repeats on the first DS3 channel for 10 minutes, beginning in privileged EXEC mode:
The following configuration examples show how each line card that supports Cisco Remote Connection Management is connected.
The configuration example in Figure 2 consists of a Cisco 12000 series router, a Cisco 7200 series router, and a Cisco 7500 series router connected to the packet over E3/T3 (POET) port adapter, and a third-party T3 DSU, such as Digital Link, Larscom, or Kentrox.
This configuration example shows a direct connection between the local (near-end) and remote (far-end) interfaces. Figure 3 shows a local (near-end) line card, installed in a Cisco GSR and a remote (far-end) Cisco 7200 series router, using the default DSU mode, cisco.
Use Cisco Remote Connection Management commands to configure the local (near-end) router to match the configuration on the remote (far-end) router. When you configure the local (near-end) line card, be sure to set the CRC to 16 or 32, and verify that the encapsulation type on the local (near-end) matches the remote (far-end). The clock source on the default DSU mode, cisco is always set to internal. The clock source on the local (near-end) line card is line by default. You can not change the Cisco 7500 series HSSI router configuration.
This section documents the Cisco Remote Connection Management feature commands. All other commands used with this feature are documented in the Cisco IOS Release 12.0 Command Summary:
To set the DSU bandwidth range, use the dsu bandwidth interface configuration command. Use the no form of this command to return to the default value.
The local and remote DSU bandwidth configuration settings must match to enable network connectivity. When connected to an external DSU, the only data transmission rates allowed are those that are configurable on DSUs in the network. A zero range value will not allow data to pass. Refer to the DSU proprietary documentation for details.
The following example shows how to set the bandwidth range to 44210 bps:
To configure the DSU mode on the Cisco 12000 series router and another device, use the dsu mode interface configuration command. Use the default DSU mode, cisco, to return to the default value.
A DSU mode must always be present in a DS3 interface configuration between two ports. Each line card interface or serial port interface can be configured to support third-party DSU modes, or the default mode, cisco. DSU mode is characterized primarily by the bandwidth control (subrate) and payload scrambling. The default DSU mode, cisco, has a default line clock source setting. The internal clock source setting transmits using a locally generated clock, while the line clock source setting (loop timing) uses the recovered receive clock. When you use a third-party DSU mode, if the local (near-end) of a connection is in line clocking mode, then the remote (far-end) must be in internal clocking mode, or in the opposite order. Clocking mode synchronization can affect the success or failure of network connectivity. To troubleshoot network connectivity, check your clock mode configuration according to the line card type.
The following example sets the DSU mode to kentrox:
To set the local (near-end) DS3 port to accept the incoming remote requests, use the dsu remote accept global configuration command. Use the no form of this command to refuse incoming remote requests.
This command ensures that the local (near-end) will accept all requests from the remote (far-end).
The following example shows how to configure the local (near-end) DS3 port to accept a remote configuration setting request by entering the dsu remote accept interface configuration command:
To set the local (near-end) DSU bandwidth, use the dsu remote fullrate interface configuration command. Use the no form of this command to return to the default value.
This command provides the lowest to highest speeds for sending and receiving data between the local (near-end) and remote (far-end) DS3 ports.
The following example shows how to enter a local (near-end) DS3 port request to set the DSU bandwidth to fullrate:
To show information that is specific to a 6DS3-SMB or 12DS3-SMB line card serial port, use the show controllers serial EXEC command.
No default behavior or values.
Be sure to specify the router slot number and serial port number when using this command. The serial ports on the 6DS3-SMB line card are numbered 0-5. The serial ports on the 12DS3-SMB line card are numbered 0-11. A single serial port consists of one coaxial connector for receiving (Rx) and one coaxial connector for transmitting (Tx).
The following example shows how to verify the controller configuration settings on the 0 DS3 serial port on a line card in slot 2:
To display information that is specific to the serial port interface hardware, use the show controller serial detail EXEC command.
No default behavior or values.
This command output displays a log message that records the number of requests that were made to a serial port on the 6DS3-SMB or 12DS3-SMB line card.
The following example shows how to use the show controller serial slot/port detail command to verify configuration on the local near-end DS3 serial port:
(Remainder of displayed text omitted from example).
To identify that a router recognizes a line card in a slot, use the show diag EXEC command.
No default behavior or values.
Be sure to specify the router slot number when using this command.
The following example shows how to enter the show diag command to verify that the router recognizes the line card in a slot:
To identify the types of line cards in all router slots, use the show diag summary EXEC command.
This command has no arguments or keywords.
No default behavior or values.
There is no need to specify the router slot number or port number when using this command.
The following example shows how to use the show diag summary EXEC command to list all of the line cards that are installed in router slots:
To display information about a line card interface, use the show interface slot/port EXEC command.
No default behavior or values.
Be sure to specify the router slot number where the line card is installed.
The following example shows how to obtain information about the 6DS3-SMB or 12DS3-SMB line card interface in slot 6:
Use the show interfaces serial slot/port EXEC command to display information about a serial interface.
No default behavior or values.
Be sure to specify the router slot number and serial port number when using this command. The serial ports on the 6DS3-SMB line card are numbered 0-5. The serial ports on the 12DS3-SMB line card are numbered 0-11.
The following example shows how to verify the configuration settings for the 0 DS3 serial port on the line card in slot 2:
| Command | Description |
|---|---|
Add/Drop Multiplexer (ADM)—A multiplexer capable of extracting and inserting lower-rate signals from or to a higher-rate multiplexed signal without completely demultiplexing the signal.
Bayonet coupling connector (BNC)—A standard cable connector, commonly used in T3 applications.
Digital signal level 3 (DS3)—Framing specification used for transmitting digital signals at 44.736 Mbps on a T3 facility.
Data service unit (DSU)—Device used in digital transmission that adapts the physical interface on a data terminal equipment (DTE) device to a transmission facility such as T3 or E3. The DSU is also responsible for such functions as signal timing. Often referred to, together with CSU, as DSU/ CSU.
Far-End Alarm and Control (FEAC)—A DS3 low-speed subchannel.
Frame check sequence (FCS)— Extra characters added to a frame for error control purposes. used in HDLC, Frame Relay, and other data link layer protocols.
High-level Data Link Control (HDLC)—Bit-oriented, synchronous data link layer protocol developed by International Organization for Standardization (ISO). Derived from Synchronous Data Link Control (SDLC), HDLC is a specific data encapsulation method on synchronous serial links using frame characters and checksums.
Management Information Base (MIB)—The set of attributes an SNMP-based management station can query or set in an SNMP agent resident in a network device.
Packet-Over E3/T3 (POET)—port adapter.
Sub-miniature bayonet (SMB)—coupling connectors.
Posted: Thu Jan 16 21:21:09 PST 2003
All contents are Copyright © 1992--2002 Cisco Systems, Inc. All rights reserved.
Important Notices and Privacy Statement.
