WAN Configuration For Point To Point Unnumbered

August 16, 1999

Lucent PortMaster (TM) Models

Each of the following Lucent PortMaster (TM) models are equipped with synchronous ports that can be used as Wide Area Network (WAN) interfaces. The synchronous ports for each unit type are listed as follows:

  • PM-2R, W1 
  • PM-2ER, W1 
  • IRX-211, S1 
  • IRX-111, S1 
  • IRX-112, S1,S2 
  • IRX-114, S1,S2,S3,S4 
  • OR-LS, W1 
  • OR-HS, W1 

Summary

Point to point unnumbered refers to connections where the interfaces connecting the routers to the WAN do not  have IP addresses. The address of the WAN port is set to a zero value (0.0.0.0) on both WAN ports.  The destination addresses are set to the ethernet IP address of the unit on the far side of the link. 

NOTE: A Point to point connection is not a frame relay connection. Lucent products Do Not support un-numbered frame relay connections. 

====ETHERNET===================== 192.168.1.0/24 ===
        |
        | E0 IP: 192.168.1.100
+-------+--------+
|       E0       |
|      IRX   A   |
|       W1       |
+-------+--------+
        |
        |
       [-] CSU/DSU
        |
        | PTP WAN
        |
       [-] CSU/DSU
        |
        |
+-------+--------+
|       W1       |
|      IRX   B   |
|       E0       |
+-------+--------+
        | 192.168.2.200
        |
====ETHERNET===================== 192.168.2.0/24 ===

Items To Verify Before You Start:

  1. Verify that there are two separate IP subnets and IP addresses for each router. Each side of the point to point connection must have its own IP subnet that does not overlap with another IP subnet. 

    2. These IP network address may be obtained from an Internet Service Provider, leased line carrier, or by using the Internic link: http://www.internic.net/. 

    If it is not planned to connect the network in question to the Internet an IP network address set aside for private use may also be used. The IP network address for private use can be found in RFC1597. The most commonly used network IP address is 192.168.0.0. 
     

  2. Verify that there is a V.35 cable to connect the PortMaster synchronous port to the CSU/DSU
  3. Verify that the CSU/DSU  is configured for external clock.
  4. Verify that the Point to point line is provisioned correctly.

Configuring The WAN Ports

In this example, assume the following: 

  • PortMaster 'A' has an ethernet IP address of 192.168.1.100 with a netmask of 255.255.255.0
  • PortMaster 'B' has an ethernet IP address of 192.168.2.200 with a netmask of 255.255.255.0
  • PortMaster 'A' is providing Internet access to PortMaster 'B'.
  • The WAN ports on both PortMaster units are represented by W1. 

The IP addresses in the following example are example only. 

# PortMaster A

Command> set address 192.168.1.100         
# Set ethernet IP address
Command> set netmask 255.255.255.0
 
Command> set w1 network hardwire
Command> set w1 address 0.0.0.0          
# This is for unnumbered. No
# address required for WAN port
Command> set w1 destination 192.168.2.200  
# Set the destination to the ethernet 
# port of the router at opposite end
Command> set w1 netmask 255.255.255.0
Command> set w1 modem on                 
# This can be on or off
Command> set w1 protocol ppp
Command> set w1 routing on               
# This defines Routing Information Protocol (RIP)
Command> set w1 mtu 1500                 
# Maximum Transfer Unit

Command> save all
Command> reset w1 

# PortMaster B

Command> set address 192.168.2.200         
# Set ethernet IP address
Command> set netmask 255.255.255.0
Command> set gateway 192.168.1.100         
# IP address of upstream router
 
Command> set w1 network hardwire
Command> set w1 address 0.0.0.0          
# This is for unnumbered. No
# address required for WAN port
Command> set w1 destination 192.168.2.100  
# Set the destination to the ethernet 
# port of the router at opposite end
Command> set w1 netmask 255.255.255.0
Command> set w1 modem on                 
# This can be on or off
Command> set w1 protocol ppp
Command> set w1 routing on               
# This defines RIP
Command> set w1 mtu 1500                 
# Maximum Transfer Unit

Command> save all
Command> reset w1 

Troubleshooting

If the port does not have an "ESTABLISHED" status do the following: 

Point to Point (PPP) negotiations can be seen and  the status of the WAN port change to "ESTABLISHED". At this point it should be possible to ping the other side. 

 
Command> set console
Command> set debug 0x51

Put the CSU/DSU into a local loopback. This will cause each packet sent to the CSU/DSU to reflect back to the WAN port. This is for testing only, the line will not function while the CSU/DSU is in a local loopback. If "LCP: Apparent Loop" is seen, the following can be determined:

  1. The WAN port on the PortMaster is transmitting and receiving data.
  2. The cable and connectors between the PortMaster and the CSU/DSU are OK.
  3. The Data Terminal Equipment (DTE) port on the CSU/DSU is ok.
  4. THE PortMaster IS FUNCTIONING PROPERLY.

If "LCP: Apparent Loop" is not seen: 

  1. Verify that the RS232-V.35 dip switch next to the WAN port is set correctly, (usually V.35)
  2. Verify that all cables are securely connected.
  3. Verify that the V.35 cable that came with the unit is being used.
  4. Other methods of equipment  troubleshooting include swapping cables, CSU/DSU units, etc.

If you get apparent loops and the status is not established but shows "CONNECTING":: 

  1. Verify the CSU/DSU settings such as clocking, etc. In most cases the CSU/DSU should be set for external clocking. The Telco provides the clock source. Verify the CSU/DSU settings with the manufacturer. 
  2. Have the telephone carrier provider test the line. Request a hard copy of the test results.  

If the port status is "ESTABLISHED", but unable to ping the other side: 

  1. Verify that the IP address for the WAN ports on both sides are in the same subnet. 
  2. Traceroute from your workstation at PortMaster to the router in question. Traceroute from the router in trouble (assuming you can get to it) back to your workstation. The problem will lie in the gap between the two traceroutes. 
  3. Verify that the "set gateway" is set to the upstream router. 

'Packet Filter' is a  powerful trouble-shooting tool .

The following  packet filter example will show all pings passing through the PortMaster where the packet filter is located. It will NOT show pings originating from the PortMaster.  

Command>  add filter p
Command> set filter p 1 permit icmp
 
To enable the packet trace [ptrace], enter the following commands:
 
Command> set console
Command> ptrace p ext
 
To disable the ptrace, enter the following commands:
 
Command> ptrace
Command> reset console