This Technical Note describes troubleshooting tips for T1 Physical Layer of a Netopia T-1 router.
This Technical Note focuses on troubleshooting techniques for a Leased Line Netopia Router and internal DSU, with an emphasis on North American T1 and Fractional T1 lines. Higher level datalink protocols like PPP, HDLC and Frame Relay are not referenced here but are the topic of another Technical Note.
Below is a list of hardware and firmware loads that this Technical Note is based upon:
| Hardware | Firmware/Version | Installed Options |
| R5300 or R5320 | 4.8.4 or later | TER/53 card, TER/20 for backup module |
| 4522/4522XL/4622/4721 | 5.3.4 or later | N/A |
None.
This is a simple guide to getting your Netopia router up and running. This guide is provided to aid you in identifying the basic problems in getting your R5300 up and running as fast as possible. This document concentrates on the Physical OSI Layer 1. Until the physical layer is cleared, concerning yourself about IP addressing and Data Link activity is irrelevant. Do not allow yourself to get caught up in troubleshooting data link protocols and IP addresses before you have deemed the physical layer as working properly.
The Netopia Router has 21 LED's. However, for this tech note the Power, Ready, and Channel 1 LED's, in conjunction with the WAN Event History, are the most helpful aides in troubleshooting your connection problems. Typical T-1 settings and LED descriptions are described as follows: Check the first screen of 'Easy Setup' when telneted or consoled to the router. The settings below are typical, but by no means the only settings possible. Many of the setting below are default and you should not need to make changes other than the number of DS0 channels for instance.
| Line Encoding | B8ZS (choose B8zs if you are not sure) or AMI |
| Framing Mode... | ESF (choose ESF if you are not sure) or D4 |
| Transmit ANSI PRMs... | No |
| Number of DS0 CHannels... | (line speed)/64 in most cases |
| First DS0 Channel... | 1 (However, this will be determined by the telephone company. This option will not be seen if you have a 24 channel full T-1 circuit.) |
| Contiguous Channels... | Yes (This will be determined by the telco but most of the time its 'yes'.This will also not be seen if your have a 24 channel full T-1 circuit.) |
| Buildout (-dB)... | 0-0.6 db (This also could be referred to by the telephone company as the LBO) |
| Channel Data Rate... | Nx64k |
| Clock Source... | 'Network' This setting is found via Quick Menus and Line Configuration then T-1 Wan Module. (Internal if the telephone company asks the DTE or CPE equipment to supply the clock) |
| Data Link Encapsulation... | PPP, HDLC, or Frame Relay This setting is found via Quick Menus and Line Configuration then T-1 |
Once you are consoled or telneted to the Netopia you will be able to follow the instructions below. For instructions on telneting or consoling to the router, use: NQG_100 Getting Started (How to Telnet/Console to your router).
We will first start off with looking at the LED lights on the router. At this point the T-1 line should be plugged into WAN 1 of the router and the router powered on. Observe the ready light and refer to the section below that is most appropriate.
This means that the Netopia is detecting no physical layer physical framing synch on the T1 line. It means your T-1 line is not communicating with the telco on even the most basic physical layer. Follow the steps below to try to resolve this problem.
Step 1. First thing before you do any typical T-1 line troubleshooting is to make sure you have a T-1 line. If you have multiple DS0's then you can be sure you have a T-1 line. DDS would be a single DS0 of either 56 or 64k. The pin out on the DDS jack would be 1,2,7,8 not the typical 1,2,4,5 for T-1. If you do find you have a DDS line, you will not be able to use a Netopia R5300. The R5200 is the Netopia DDS router. If you have confirmed that the line is in fact T-1, then continue with the instructions below.
To effectively use this technote please telnet or console into the R5300 and go from the router main menu to 'Statistics/Logs'-->'Wan Event History'
Step 2. Check the Wan Event History.Do you see a line activation message? A normal T-1 Activation message for a full T1 will read Device Restarted and above will read WAN: T1 1 Activated at 1536 Kbps. There may be events above the activation message if you have the datalink layer up as well. If so, go immediately to the situation regarding a Solid Green Ready Light Situation 3.
If the Wan is not communicating with the telco you will see Device Restarted' ....T1: Receiving red alarm - loss of signal'....'T1: Line is unavailable, due to excessive errors" with no other events. This is confirming what the LED Ready light status is also telling us. Go to step 2. Double-check the physical properties of the T1 configuration.
This is a good point to talk about any alarm conditions logged in the WAN Event History. Do you see the Netopia declaring any alarm condition? If so, the description below will guide you in understanding what some of these alarm conditions mean.
There are two major alarm conditions: Red Alarm and Yellow Alarm.
A red alarm means one of two things. There is either no incoming signal, a Loss Of Signal being received in the device that is in the red alarm state or there is no frame synchronization (you will hear people say there is "no synch on the line").
These are also referred to as a loss of signal Loss Of Frame. LOS is cleared when appropriate 1 's density is received at the network interface. Every vendor implements this a bit differently; Netopia declares a failure of 1's density in about 2-3 seconds.
What could cause the incoming loss of signal or loss of frame?
Make sure you are using a fully populated straight-through CAT-5, RJ-45 or RJ-48 cable. T-1 requires pins 1 rx,2 rx, 4 tx,5 tx and most CAT-3 cables will not work properly. By using the fully populated CAT-5 you are removing any guesswork on whether pins 1,2,4,5 are pinned out properly.
Is the wall jack you are plugging into an extended demarc or are you testing at the demarc?
Do not trust the wiring from the demarc to the wall jack when you are trouble shooting an LOS problem. The telco is generally only responsible to the demarc so test the connection from the demarc (usually found in the phone closet of your office building) to the current wall jack itself. Then find the closest possible location to the demarc. If the router is in a solid green ready state at the demarc but in a flashing ready state at a certain wall jack then you know the problem exists somewhere between those two points.
What causes a Loss Of Frame (LOF) or Out Of Frame (OOF)?
Do you have the proper framing format chosen in your router configuration properties? Most modern circuits are ESF for framing, and B8ZS for line encoding. Go to 'Quick Menus' , 'Line Configuration' and 'T-1 Setup' and check the framing format.
Who is supplying clock on the circuit?
Always start with 'Network' clock. You can find the Netopia clock settings in 'Quick Menus' and 'Line Configuration'. Clock source is almost always Network unless the telephone company has specifically told you to supply clock on the circuit. (Many times on point to point T-1 with R5300 to R5300 you will choose one of the Netopia's to supply clock. ONLY choose internal clock if you have been instructed to supply clock by the telephone company. If the telephone company does not know who is clocking the line you need to speak with someone else at the telco. You must know where the clock is coming from on your T-1 line! Without this knowledge you may complicate your troubleshooting efforts.
Call the telco that is responsible for your T1 line. Ask to see if the circuit was installed and 'turned up'. Ask the telco technician to run a loopback to the smartjack and router (CSU/DSU of the router). Was the loopback successful? If so tell the technician that your router is not communicating with their line. Ask them if the line is stuck in a looped state. Confirm again how many channels your T-1 line should be provisioned for? A telephone technician could have left the line in a looped condition accidentally after testing. The line must NOT be in a looped state for proper T1 line activation for the Netopia router.
A Yellow alarm or RAI (Remote Alarm Indication) is sent by a device at the remote end to indicate it is not receiving a signal. Many times this yellow alarm is being sent from the router at the remote side. What is useful about a yellow alarm is that the device receiving the yellow alarm knows that physical framing (OSI 1) is being received correctly. Why is this helpful for troubleshooting? Well, for one thing now you know the remote transmit to receive path is working properly. This of course does not tell you what is wrong, just that something in the path of remote receive and local transmit is not working properly.
There are two options: either the Netopia currently is not properly powered ON or the Netopia is not receiving power through the power port in the right rear back panel.
Step 1. If you cannot telnet or console to the router first start with items that are the easiest to check. Make sure the router is powered on! (The Netopia power button when pushed in will leave the power button flush with the blue case) Make sure the power cable is plugged into the router. Is the power brick plugged into a known working powerstrip that is displaying power? If so the Power LED (LED #1 in the diagram above) on the Netopia should be solid green and flush with the front panel of the router. If the power button is flush but not illuminated then go to step 2.
Step 2. Are you using the power brick that came with the router? Do NOT use a non-Netopia power brick! Is it plugged into a working powerstrip? Have you tested with another known working powerstrip? If so, do you have multiple Netopia routers so you have the option of testing with another Netopia power brick or router? If a different power brick works, please call Netopia support for a replacement of the power brick.
If you have checked all of Step 1 and have no ready light whatsoever please call Netopia support. If you now have a flashing red Ready light, move to Situation 1. If you have a solid green ready light then move on to Situation 4.
There are very few reasons to have a solid Red Ready Light!
First, you may not have the proper firmware installed on the Netopia. The R5300 did not exist as a product before 4.3.3 firmware. If you purchased this as a new product it will never ship out with a firmware below 4.3.3 ( in fact most will have 4.8x or later, and this will not be an issue). However, if you have 4.3.1 firmware it will not recognize the Netopia as a R5300 and may report the router as a R1300. This is the Netopia motherboard because the wanlet is being disregarded. What does the main menu report via the console or telnet session? Is the router reporting itself as an R1300 or does it report an R5300?
If you are telneted or consoled into the Netopia and the router reports an R1300, please go to Upgrading Router Firmware via TFTP or Xmodem File Transfer.
Firmware can also be obtained at ftp.netopia.com/pub/router/firmware or tftp.netopia.com. Hopefully, either by upgrading the firmware or reseating the wanlet by now you will have a Flashing Red Ready Light or even better a Solid Green Ready Light
If you are performing a wanlet upgrade (upgrading the router from another Netopia model) please recheck your work on the wanlet upgrade kit instructions. If you have rechecked your wanlet upgrade installation and now have a flashing Red Ready Light then move to Situation 1. If the Ready light is now solid green you should have physical layer frame synch with the T-1 line.
You now have T-1 line activation with the data link layer up. You should see the following events (depending on your datalink encapsulation the top most line may report HDLC, PPP, or Frame Relay) see our Data Link Layer 2 and 3 troubleshooting technotes for more specifics on Netopia Router Data Link Layer 2 events:
WAN Event History
Current Date -- 9/13/01 03:41:36 PM
-Date-----Time-----Event------------------------------------------------------
09/13/01 15:41:26 HDLC: IP up, channel 1, rem: 192.168.3.2
09/13/01 15:41:26 HDLC: Channel 1 up
09/13/01 15:41:26 WAN: T1 1 activated at 1536 Kbps ?---(This should mean you have Green Ready light! )
09/13/01 15:41:23 --Device restarted-----------------------------------------
By following the troubleshooting steps in this Technical Note, this should eliminate connection or communication problems between the Netopia Router and remote equipment over a Leased Line on the physical layer. If the Leased Line still does not work properly, please contact the Telephone Company or Leased Line provider. They will be able to check the Leased Line configuration and perform loopback and bit-error tests to determine the source of any Leased Line problem. If you have exhausted all suggestions within this technote please contact Netopia Tech Support.