84.3. ADSL lines

84.3.1. How can I verify if an ADSL line is active?

Verify the state of the USB modem: “USB” and “ADSL” LEDs must be green and continuous (not blinking!).

[Warning]Warning

ADSL” LED is green and continuous even if the logical layer is down.

[Warning]Warning

When “USB” LED is red, the USB connection isn't active!

Type the d d adsl command and verify that:

  • The modem is connected and correctly working: MODEM-STATE:CONNECTED;

  • ADSL carrier is active: LINE-STATE:UP;

  • There is traffic on the line: Trh-OUT and Trh-IN columns with values different from zero and increasing over time.

For example:

[10:08:48] ABILIS_CPX:d d dsl

RES:Dsl-1 ---------------------------------------------------------------------
       Linea ADSL          
       LINE-STATE:UP                LINE-MODE:ADSL       ADSL-ANNEX:A
       MODEM-STATE:CONNECTED        MODEM-FAILURE:NONE
       MODEM-NAME:Abilis-ADSL2+     MODEM-MAC:00-0F-C9-14-7A-CF    FW:3.18
       ----------|---INPUT---|--OUTPUT---|------------|---INPUT---|--OUTPUT---|
       SPEED     |    8.128 M|    0.829 M|ATTENUATION |       20.8|       18.8|
       SN-MARGIN |       18.7|       18.7|INTERLEAVE  |       0.25|       0.25|
       - ATM level diagnostics ------------------------------------------------
       VPI  VCI    QoS    State       Bw-In     Bw-Out 5sec-Thr-In 5sec-Thr-Out
                                                       5min-Thr-In 5min-Thr-Out
       ------------------------------------------------------------------------
       8    35     NORMAL UP        7.361 M    0.751 M      15.4 K       8.14 K
                                                             235 K       29.0 K
       ------------------------------------------------------------------------

It's possible to restart the USB modem, using the command debug res:dsl-1 lsn:254. By typing the command debug res:dsl-1 lsn:0, it's possible to display all available debug commands.

[10:08:48] ABILIS_CPX:debug res:dsl-1 lsn:254

RES:Dsl-1 --------------------------------------------------------------------
       BufferLength:57     Date/Time:18/01/2017 12:37:50 TraceTime:<NotRunning>

DSL restart has been queued, it will be executed ASAP.

84.3.2. Why the xDSL line is slow?

If an ADSL line is too slow, you have to do the following verifications.

  1. Verify that the ERRORS parameter in the ADSL resource isn't increasing over time.

    [10:08:48] ABILIS_CPX:d s dsl
    
    RES:Dsl-1 ---------------------------------------------------------------------
           Linea ADSL                         
           --- Cleared 3 days 20:47:27 ago, on 13/01/2017 at 19:29:45 -------------
           -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
           LINE-DOWN  |          0|           |MODEM-DISC |          0|           |
           LINE-UP    |          1|           |MODEM-CONN |          1|           |
           AUTORST-L  |          0|           |MANUALRST  |          0|           |
           AUTORST-U  |          0|           |
           ------------------------------------------------------------------------
           - ATM level statistics -------------------------------------------------
           -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
           VC-UNKNOWN |          0|           |HEC-ERR    |          0|           |
           AAL5-ERR   |          0|          0|MISALIGNED |          0|           |
           DROPPED    |          0|          0|
           ------------------------------------------------------------------------
           VPI:8    VCI:35     
           -----------|---INPUT---|--OUTPUT---|-----------|---INPUT---|--OUTPUT---|
           AAL5-SDU   |    4572016|    4375998|AAL5-CHAR  | 2084385512|  553960360|
           ERRORS     |      46435|          0|CELLS      |   46435278|   13655724|
           ------------------------------------------------------------------------
  2. Verify the bandwidth occupation with the d d dsl command.

    [10:08:48] ABILIS_CPX:d d dsl
    
    RES:Dsl-1 ---------------------------------------------------------------------
           Linea ADSL                    
           LINE-STATE:UP                LINE-MODE:ADSL       ADSL-ANNEX:A
           MODEM-STATE:CONNECTED        MODEM-FAILURE:NONE
           MODEM-NAME:Abilis-ADSL2+     MODEM-MAC:00-26-75-F0-17-BA    FW:3.18
           ----------|---INPUT---|--OUTPUT---|------------|---INPUT---|--OUTPUT---|
           SPEED     |   11.616 M|    1.165 M|ATTENUATION |       18.4|        8.2|
           SN-MARGIN |       11.9|        7.3|INTERLEAVE  |       0.25|       0.25|
           - ATM level diagnostics ------------------------------------------------
           VPI  VCI    QoS    State       Bw-In     Bw-Out 5sec-Thr-In 5sec-Thr-Out
                                                           5min-Thr-In 5min-Thr-Out
           ------------------------------------------------------------------------
           8    35     NORMAL UP       10.520 M    1.055 M      20.9 K       28.7 K
                                                                20.9 K       27.6 K
           ------------------------------------------------------------------------

    If the input and/or output throughput has a value near to the maximum Bandwidth available, the line is saturated.

  3. With the d nat maps command it's possible to display the IP addresses and ports of the current NAT sessions.

    [12:48:33] ABILIS_CPX:d nat maps
    
    Number of records in standard table: 4
    
    S A TYPE SRC-ADDRESS     SP/ID DST-ADDRESS     DP/ID ALS-ADDRESS     ALIAS  TM
    -------------------------------------------------------------------------------
    I S UDP  192.168.000.008 45379 128.006.229.020 57333 080.080.080.080 7668   164
    I S TCP  192.168.000.008 1521  193.205.079.111 5542  080.080.080.080 52450  132
    I S UDP  192.168.000.008 45379 140.078.149.003 31782 080.080.080.080 7630    70
    I S FTPd 192.168.000.003 4551  212.029.147.233 20    080.080.080.080 7455   172
    I S UDP  192.168.000.008 45379 143.225.070.229 35236 080.080.080.080 7631    70
    I S UDP  192.168.000.008 45379 221.250.120.075 42197 080.080.080.080 7659   136
    I S UDP  192.168.000.008 45379 069.246.011.036 32876 080.080.080.080 7645   104
    ...

    In this case there is a FTP session that could use a lot of bandwidth.

84.3.3. Why can't I reach any website?

Verify the number of current NAT sessions with the d d nat command.

[12:48:33] ABILIS_CPX:d d nat

RES:Nat -----------------------------------------------------------------------
       Network_Address_Translator
       STATE:READY
       -----------|--- CUR ---|-- PEAK ---|--- MAX ---|
       LINKS      |        998|       1000|       1000|
       ------------------------------------------------

If the value of CUR (current) parameter is near to the value of MAX parameter, probably some sessions could be discarded.

[Tip]Tip

Remember to check also the IPACL table.