Cisco Cisco 3G Wireless WAN (1xRTT, EVDO Rev A Rel 0) HWIC - Verizon Information Guide
Q&A
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I have a 3G HWIC with CDMA that is now activated with Rev A, but has problem pinging
or being pinged.
Make sure the syntax for the CHAT script is correct, as follows:
Make sure the syntax for the CHAT script is correct, as follows:
chat-script cdma "" "ATDT#777" TIMEOUT 60 "CONNECT.
Activation is successful but I am experiencing data connectivity failures, interface
flapping, reset, etc. What is wrong?
The service provider drops the connection if the traffic is not sourced from the IP address the
provider assigned to the cellular interface; the command is source ip validation. To avoid this
occurrence, ensure that the LAN traffic going over the cellular interface is restricted by using
access lists, Network Address Translation (NAT), or generic routing encapsulation (GRE).
The service provider drops the connection if the traffic is not sourced from the IP address the
provider assigned to the cellular interface; the command is source ip validation. To avoid this
occurrence, ensure that the LAN traffic going over the cellular interface is restricted by using
access lists, Network Address Translation (NAT), or generic routing encapsulation (GRE).
To determine if the interface flapping and connectivity problems are caused by source IP
validation, enable the following debugs:
validation, enable the following debugs:
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debug dialer
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debug chat
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debug ppp negotiation
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debug ppp error
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debug ppp event
Note: This debug requires that you have enable service internal enabled.)
If you see TERMREQ as shown in the following debugs, it implies that the service provider is
terminating the call:
terminating the call:
Jul 20 19:15:31 UTC: Ce0/0/0 LCP: I TERMREQ [Open] id 68 len 4
*Jul 20 19:15:31 UTC: Ce0/0/0 LCP: O TERMACK [Open] id 68 len 4
*Jul 20 19:15:31 UTC: Ce0/0/0 PPP: Sending Acct Event[Down] id[1A]
*Jul 20 19:15:31 UTC: Ce0/0/0 IPCP: State is Closed
To troubleshoot further, shut down all other interfaces except the cellular interface and issue a
ping from the router. If the ping succeeds, reconfigure other interfaces one by one and verify
what traffic escapes the access lists or NAT to cause the service provider to terminate the call.
ping from the router. If the ping succeeds, reconfigure other interfaces one by one and verify
what traffic escapes the access lists or NAT to cause the service provider to terminate the call.
My cellular interface regularly bounces. When the cellular interface is temporarily up/up,
I can get to the Internet. The bouncing then takes down the tunnel interfaces. If I shut
the tunnel interfaces and turn off Simple Network Management Protocol (SNMP), Cisco
Discovery Protocol, and Network Time Protocol (NTP), then the cellular interface does
not bounce, and I still can access the Internet with no problem.
When traffic is not sourced from the IP address that the service provider assigns to the cellular
interface and goes over the provider network, the connection is dropped (source IP validation).
In addition, verify the following:
When traffic is not sourced from the IP address that the service provider assigns to the cellular
interface and goes over the provider network, the connection is dropped (source IP validation).
In addition, verify the following:
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Tunnels should be sourced from the cellular interface.
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A "default static route" with a higher metric than the wireline connection should be pointing
to a tunnel interface that is pointing to the cellular interface as the source IP.
to a tunnel interface that is pointing to the cellular interface as the source IP.
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The router should have a static route for the peer of that tunnel pointing to the cellular