Troubleshooting guide

address, make sure you have only one static default route in the configuration (for example, IP route 0.0.0.0
0.0.0.0 192.168.1.1).
For the example above, if you already have a correct static default route and cannot ping Internet addresses,
contact your ISP to resolve the routing issue.
If the ping test fails, you see output similar to the output shown below. In this case, continue with the
troubleshooting steps that follow.
C:\>ping 192.168.1.1
Pinging 192.168.1.1 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Ping statistics for 192.168.1.1:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),
Approximate round trip times in milli−seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
Is the bridge port in a forwarding state?
For your Cisco DSL Router to forward packets to your ISP, your bridged interface must be in a forwarding
state. If your bridged interface is in a blocking state, there is a loop in your network that you have to remove
before you are able to pass traffic. The most common cause of a loop in a DSL network is having two bridged
DSL circuits to the same ISP.
Router#show spanning−tree
Bridge group 1 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address 0001.96a4.a8bc
Configured hello time 2, max age 20, forward delay 15
Current root has priority 32768, address 0000.0c25.36f4
Root port is 3 (ATM0), cost of root path is 1562
Topology change flag not set, detected flag not set
Number of topology changes 2 last change occurred 00:00:56 ago from Ethernet0
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0, aging 300
Port 2 (Ethernet0) of Bridge group 1 is forwarding
Port path cost 100, Port priority 128, Port Identifier 128.2.
Designated root has priority 32768, address 0000.0c25.36f4
Designated bridge has priority 32768, address 0001.96a4.a8bc
Designated port id is 128.2, designated path cost 1562
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 44, received 0
Port 3 (ATM0) of Bridge group 1 is forwarding
Port path cost 1562, Port priority 128, Port Identifier 128.3.
Designated root has priority 32768, address 0000.0c25.36f4
Designated bridge has priority 32768, address 0000.0c25.36f4
Designated port id is 128.17, designated path cost 0
Timers: message age 2, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 2, received 53
Cisco DSL Router Configuration and Troubleshooting Guide