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Unstable 877 on ADSL 2+

Andy White


I'm based in the UK and have had a new ADSL line put into a remote site by BT (British Telecom).  It is an ADSL 2+ line and I have configured it as A VPN back to our site.  All is working but the line is unstable and it goes down for 20 seconds every 20 mins or so, sometimes it is longer or less,quite random, this also happens if I take the VPN config off.  I phoned BT and they said they don't support Cisco 877s or 1800s that use the Alcatel chipset and said we should get rid of using Cisco (what!!).  Anyway is there a work around, do I need to update my ADSL modem firmware (not sure how you do this) or are they right?

Some info:

Show flash

Directory of flash:/

    2  -rwx    21910432   Mar 1 2002 00:22:01 +00:00  c870-advipservicesk9-mz.124-24.T8.bin

    3  -rwx         660  Jun 11 2013 10:19:32 +01:00  vlan.dat

27611136 bytes total (5693440 bytes free)

Show version

Cisco 877 (MPC8272) processor (revision 0x400) with 118784K/12288K bytes of memory.

Processor board ID FGL153224W1

MPC8272 CPU Rev: Part Number 0xC, Mask Number 0x10

4 FastEthernet interfaces

1 ATM interface

128K bytes of non-volatile configuration memory.

28672K bytes of processor board System flash (Intel Strataflash)

sh dsl int atm 0


Alcatel 20190 chipset information

                                   ATU-R (DS)                      ATU-C (US)

Modem Status:               Showtime (DMTDSL_SHOWTIME)

DSL Mode:                    ITU G.992.5 (ADSL2+) Annex A

ITU STD NUM:                0x03                            0x3

Chip Vendor ID:              'STMI'                          'TSTC'

Chip Vendor Specific:      0x0000                    0x0510

Chip Vendor Country:       0x0F                      0xB5

Modem Vendor ID: 'CSCO'                          'TSTC'

Modem Vendor Specific:   0x0000                    0x5100

Modem Vendor Country:  0xB5                      0xB5

Serial Number Near:         FGL153224W 877-K9   12.4

Serial Number Far:           Chip ID:     C196P (1)

DFE BOM:                      DFE3.0 Annex A (1)

Capacity Used:               100%                            100%

Noise Margin:                 5.5 dB                          5.0 dB

Output Power:                20.5 dBm                        12.5 dBm

Attenuation:                   36.0 dB                         19.0 dB

FEC ES Errors:              758                             307359

ES Errors:                       3                              27923

SES Errors:                    1                              3272

LOSES Errors:                1                              2315

UES Errors:                    0                              1667

Defect Status:             None                            None

Last Fail Code:  None

Watchdog Counter: 0x11

Watchdog Resets: 0

Selftest Result: 0x00

Subfunction:     0x00

Interrupts:      23720321 (0 spurious)

PHY Access Err:  0

Activations:     149

LED Status:      ON

LED On Time:     100

LED Off Time:    100

Init FW:         init_AMR-3.0.014_no_bist.bin

Operation FW:    AMR-3.0.014.bin

FW Source:       embedded

FW Version:      3.0.14

                 DS Channel1      DS Channel0   US Channel1       US Channel0

Speed (kbps):              0                13444                    0               804

Cells:                         0                  10347                   0           1445512

Reed-Solomon EC:     0                   8991                    0           4347917

CRC Errors:                0                       3                     0            161230

Header Errors:            0                        3                    0            257708

Total BER:                0E-0           1098E-9

Leakage Average BER:      0E-0           1098E-9

Interleave Delay:         0                8             0                63

                        ATU-R (DS)      ATU-C (US)

Bitswap:               enabled            enabled

Bitswap success:          0                   0

LOM Monitoring : Disabled

Thanks for your time


Accepted Solutions

adsl_alc_20190_0.0.026.bin Is the FW you want. This has been specifically designed for the DSLAMs in the UK.

View solution in original post


paolo bevilacqua
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If you search the forum there are various threads on the subject, with the information have asked for.

I've seen some, but they are quite old posts.  I will continue to look.