Troubleshooting
Internet Connection
Related SMT screens and CI commands:
- SMT Menu 1, 4
- SMT Menu 24.1 and 24.4
-isdn loop
-dev dial
Some basic knowledge about Internet Connection Setup
Before we start any verification or troubleshooting of Internet setup, let us first give a brief introduction of the connection setup sequence. Any PPP call to Internet or other (ISDN) router can be divided into the following steps:
- Dialing
- LCP negotiation
- Authentication ( it can be None/PAP/CHAP)
- NCP negotiation ( NCP can be IPCP, BACP, BCP, CCP, IPXCP)
The Prestige provides a very clear log for each step of the call setup. The following shows the messages displayed in each steps. If a step fails, an error message is displayed.
Start Dialing chan<1> phone<20301> <-------------
Dialing Call CONNECT speed<64000> type<2> chan<0> <------- Dial OK ( After call is up, Prestige will start LCP negotiation )
CHAP login to remote OK! <------------------------- Auth OK IPCP negotiation started <------------------------- Ipcp negotiation |
Internet connection verification steps:
Internet connection test failed:
Some common problem troubleshooting examples
Dial no number |
This could mean that your ISDN line is not up.
Dial Fail *** LINK IS NOT AVAILABLE |
This could mean that your two channels are connected to other sites (or A/B adapter in use).
- Call didn't connect - Try again later and also verify the phone number.
Dialing chan<1> phone(last 9-digit): 40202 ### Hit any key to continue.### Dial no answer |
This means the far-end is not answering.
Dialing chan<1> phone(last 9-digit): 40202 ### Hit any key to continue.### Dial busy |
This means the far-end is busy.
Dialing chan<1> phone(last 9-digit): 40202 ### Hit any key to continue.### Dial timeout |
This means you have been timeed out in making a connection. Please refer to next chapter for more detailed discussion on this.
Dialing chan<1> phone (last 9-digit): 40201 ### Hit any key to continue.### Call CONNECT speed<64000> type<2> chan<0> LCP opened CHAP login to remote failed LCP closed Recv'd TERM-REQ Recv'd TERM-ACK state 5 LCP stopped |
TRY: Verify username and password with your ISP again or retype the username and password field again. When you retype the name and password and hit return at 'Press Enter to confirm or Esc to Cancel', if you don't see 'Saving to ROM' message, then your original entry is the same as your retry, this means maybe the name/pw from the ISP is incorrect. You must call your ISP and verify the name and password again.
- IP address been rejected by your ISP
Dialing chan<1> phone (last 9-digit): 40201 ### Hit any key to continue.### Call CONNECT speed<64000> type<2> chan<0> LCP opened CHAP login to remote OK! IPCP negotiation started IPCP opened Recv'd TERM-ACK state 4 LCP stopped |
sys log disp:
" PP09 WARN Local IP mismatch, proposed 192.68.135.183,
PP09 WARN neg'd 204.247.1.1, make sure RIP is turned on"
This means that you configured your Prestige Menu 3.2 as 192.68.135.183, but the ISP thinks you should be 204.247.1.1. The Prestige dropped the call for you, because even if the call is up, your network will still be unable to talk to the Internet!
TRY: 1. If you have a class C network of 204.247.1.0/24, then you should change your Menu 3.2 to use that address. 2. If you have only one IP address 204.247.1.1/32, then you should configure your Prestige to enable Single User Account (SUA) ( For more information on how to configure SUA, please refer to application note. )
Dialing chan<1> phone (last 9-digit): 40201 ### Hit any key to continue.### Call CONNECT speed<64000> chan<1> prot<1> |
You see the call connected, but nothing else after that . After a while it says Line
down. This could be because of the low level protocol mismatch. Let's say you use 64K to
dial into a X.75 or V.120 only router.
TRY: Contact your ISP and make sure they use 'Clear Channel' ISDN protocol, or change your Telco option to X.75 or V.120 ( for DSS1 or 1TR6 only).
Dialing chan<1> phone (last 9-digit): 40201 ### Hit any key to continue.### Call CONNECT speed<64000> chan<1> prot<1> LCP up CHAP send response CHAP login to remote OK! IPCP negotiation started BACP stopped IPCP up LCP down IPCP down LCP stopped |
The call connected, IPCP was up, but still the call dropped. The call could have been dropped by the far-end for some unknown reason. You need to verify the problem with your ISP. Sometimes if the far-end is using Ascend Pipeline for your connection, they will let IPCP up and check the IP address, if IP address is not the same as what's configured in their 'Connection Profile', they would drop the call and give no log about it!
For any other unknown reason, you have to look at the packet trace to decide what went wrong. To collect the trace,
Summary:
Failure reasons | Actions |
Dial failed | - check disconnect cause - go to SMT memu 24.1 to verify that channel status is not DOWN. If DOWN, it might be ISDN Init failure. - Do ISDN loopback test |
Authentication failed | - check name and password |
Lcp negotiation failed | - trace PPP packets |
Ipcp negotiation failed | - check if IP address is correct - check if IP is turned on in a remote node. - check if SUA is needed |
All others | - collect PPP traces |
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