78.3. ADSL/HDSL lines

78.3.1. 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.

78.3.2. How can I verify if a HDSL line is active?

Verify the state of DCE3 modem: if alarm LEDs (Alarm, KO, etc) are on and blinking, there can be a fault on public network.

Type the d de fr command and verify that:

  • LMI state is active: STATE:LMI-UP;

  • DLCI state is active: DLCI STATE: ACT;

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

For example:

[10:41:37] ABILIS_CPX:d de fr-1

RES:Fr-1 - FR over Dedicated Line (DL) ----------------------------------------
       - Frame Relay ----------------------------------------------------------
       STATE:LMI-UP
       DLCI     State     Cong       MaxThr CurMaxThr  5sec-Thr-Out 5sec-Thr-In
                Cir       Bc      StepConst   MaxThr%  5min-Thr-Out 5min-Thr-In
                Tc        Be           Step      Cir%  MaxFrame-Out MaxFrame-In
       ------------------------------------------------------------------------
       20       ACT       NO         256000    256000         37488       51392
                256000    256000          4      100%         52968       51976
                1.000     0               5      100%          1504        1504
       ------------------------------------------------------------------------
       - Link -----------------------------------------------------------------
       +--------+--- Global ----+------- P-Link -------+------- S-Link -------+
       | STATE: |     READY     |        READY         |   LINK-NOT-PRESENT   |
       +--------+---------------+----------------------+----------------------+

78.3.3. Why the xDSL line is slow?

If an ADSL/HDSL 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.

78.3.4. 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.