Using Synchronous Leased Lines   14

  This chapter describes how to set up a synchronous leased line between a PortMaster 4 and another PortMaster product. The chapter provides guidelines for configuring both ends of the connection and includes the following topics:

•  "Overview of Leased Line Connections" on page 14-1
•  "Configuring a Leased Line Connection" on page 14-2
•  "Troubleshooting a Leased Line Connection" on page 14-4

  See the PortMaster 4 Command Line Reference for more information about commands used in the chapter.

  You can also configure the PortMaster 4 using the PMVision application for Microsoft Windows, UNIX, and other platforms supporting the Java Virtual Machine (JVM). PMVision replaces the PMconsole interface to ComOS.

       Overview of Leased Line Connections

  Leased line connections use leased or dedicated lines to establish a permanent connection between two routers. Once the connection is established, it remains available on a continuous basis whether or not network traffic exists between the two locations. Leased line connections have the required channel service unit/digital service unit (CSU/DSU) built in. The CSU/DSU takes digital data in the format used by the router and translates it into the digital format used by the leased line. Leased line connections also require a carrier that provides an external clock signal.

  PortMaster routers support leased line connections using synchronous ports and the PPP protocol. In this configuration, one PortMaster is usually connected to another PortMaster or other router over a leased line where each router uses its own Ethernet address for the serial link--known as  IP unnumbered--and the address of the other end is discovered dynamically. In this way, a dedicated high-speed connection is established between two routers located at separate sites.

  If you are connecting two networks together for the first time, make sure the networks are not overlapping subnets. For more information on network numbers and subnetting, see Appendix A, "Networking Concepts."

  In the leased line configuration described in this chapter, the Ethernet address of the PortMaster routers is used as the address for the serial link in a point-to-point unnumbered serial connection. Because the PortMaster relies on an external clock signal, you do not need to set the speed on the synchronous port. The port speed is whatever the carrier sends. If you choose to set a speed, it is used for administrative notation only and does not affect the operation of the port.

  PortMaster synchronous ports support leased line connections from 9600bps to T1 (1.544Mbps) or E1 (2.048Mbps) speeds. Synchronous ports used for leased line connections are configured for PPP operation and can have input and output filters for network security.

  Note ¯ The PortMaster 4 also supports numbered IP interfaces on leased lines, but Lucent does not recommended this method because it wastes IP address space.

 

       Configuring a Leased Line Connection

  Before you configure a synchronous serial port for a network hardwired leased line, you must configure global settings on the PortMaster 4, and you must configure the Ethernet interface. Follow the procedures in this section to configure a T1 or E1 line for leased line service.

       Configuring Global Settings

  Follow this procedure to configure the global settings on the PortMaster 4.

  1. Set the IP address of the gateway router.

  Command> set gateway Ipaddress

  2. Set the name of the PortMaster on the other end of the connection.

  Command> set sysname [String]

  3. Save the configuration.

  Command> save  all 

       Configuring Ethernet Interface Settings

  Note ¯ Lucent recommends that you configure Ether1 if you configure only one Ethernet interface. If you configure both, you must connect them to separate Ethernet segments. Ether0 operates at 10Mbps and is physically on the manager board. Use Ether1 for netboots, SNMP, RADIUS, and syslog .

  Follow this procedure to configure the Ethernet interface on the PortMaster 4:

  1. Set the IP address of the Ethernet interface.

  Command> set ether1 address Ipaddress

  2. Set the netmask of the Ethernet interface.

  Command> set ether1 netmask Netmask

  3. Set the broadcast address.

  Command> set ether1 broadcast high

  4. Enable RIP routing on the interface.

  Command> set ether1 rip on

  See the PortMaster 4 Command Line Reference for information about RIP-2.

  5. Save the configuration.

  Command> save all

  6. Reset the slot.

  Command> reset slot10

       Configuring the Synchronous WAN Port

  Follow this procedure to configure the synchronous WAN port on the PortMaster 4 for leased line service:

  1. Enter the show boards command to determine the identification number of the line board you want to configure.

  The board identification number is the same as the number of the slot in which the T1 or E1 module is installed.

  Command> show boards

  2. Set the view to a slot with an installed T1 or E1 line board.

  Setting the view for a specific board gives you administrative access to that board.

  Command> set view Slotnumber

  Command Slotnumber>

  The slot number appears in the prompt to identify the board you are configuring.

  3. Set a line on the line board for T1 or E1.

  Command Slotnumber> set Line0 t1|e1

  4. Save the configuration.

  Command Slotnumber> save all

  5. Reset the slot.

  Command Slotnumber> reset Slotnumber

  6. Set the interface for network hardwired.

  Command Slotnumber> set W1 network hardwired

  7. Set the protocol.

  Command Slotnumber> set W1 protocol ppp

  8. Set the destination IP address.

  If you are not sure of the IP address on the other end of the connection, you can set the IP destination to 255.255.255.255 and the PortMaster attempts to learn the address.

  Command Slotnumber> set W1 destination Ipaddress

  9. Set the netmask.

  Command Slotnumber> set W1 netmask Netmask

  10. Turn off modem control.

  Command Slotnumber> set W1 cd off

  11. Turn on RIP routing.

  Command Slotnumber> set W1 rip on

  See the PortMaster 4 Command Line Reference for information about RIP-2.

  12. Set the maximum transmission unit size.

  Command Slotnumber> set W1 mtu MTU

  13. Reset the slot and save the configuration.

  Command Slotnumber> reset  Slotnumber
Command Slotnumber> save  all 

  For more information about synchronous ports, refer to Chapter 6, "Configuring a Synchronous WAN Port."

       Troubleshooting a Leased Line Connection

  Use the information in this section to debug your configuration.

  If you have trouble with a leased line connection, verify the following:

•  Enter the following commands to view the PPP negotiation on port W1, if this is the port you are using:

    Command> set  console  W1
  Command> set  debug  0x51
   Command> reset  W1

    For information about the interpreting the results of the debug command, refer to the PortMaster Troubleshooting Guide.

    After you verify that the PPP negotiation is correct, enter the following commands to turn off the debug utility:

    Command> set  debug  off
   Command> reset  console 

•  Verify that the error counters are 0 (zero) except for abort errors. If your counters are nonzero, the problem is external to the PortMaster.

    Note ¯ CRC errors will occur if the leased line cable is ever unplugged from the PortMaster.

•  Verify that you are using the correct cable and that it is attached securely to the correct port. Not all WAN ports are capable of the same speeds.
•  If you have a Cisco router on the other end of your connection, make sure that it is running Cisco's software release 9.14(5) or later and is using PPP encapsulation, not High-Level Data Link Control (HDLC).
•  If the framing errors are greater than 0, verify that the router on the other end of the connection is running the PPP protocol.
•  If you still have problems, enter the following commands:

    Command> set  debug  0x51
   Command> set  console  C0

    Then set the line for local loopback:

    Command> set  Line0 loopback on 

    You should see the following message:

    LCP_APPARENT_LOOP

    For more information about the interpreting the results of the debug command, refer to the PortMaster Troubleshooting Guide.

•  If the local loopback shows network connectivity in the local router, take the line out of loopback and set line loopback on the remote end of the connection. If the remote loopback test does not show network connectivity in the remote router, the problem is either in the configuration of one of the CSU/DSUs or in the line itself.
•  When you finish, enter the following commands to turn off the debug utility:

    Command> set  debug  off
   Command> reset  console 

•  Contact your carrier to review your configuration and the status of their line.