cancel
Showing results for 
Search instead for 
Did you mean: 

Troubleshooting Psychosis: router LCP down, loss of sync

myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Reconnected the DG834G v3
It has been running for almost an hour with no restarts. The internet seems pretty slow though. Current logs (note I have restarted the router twice, read on for details):
Sun, 2002-09-08 12:00:20 - Initialize LCP.
Sun, 2002-09-08 12:00:20 - LCP is allowed to come up.
Sun, 2002-09-08 12:00:26 - Administrator login successful - IP:192.168.0.2
Sun, 2002-09-08 12:01:20 - Initialize LCP.
Sun, 2002-09-08 12:01:20 - LCP is allowed to come up.
Sun, 2002-09-08 12:01:21 - CHAP authentication success
Wed, 2013-11-13 20:25:46 - <NTP> Receive NTP Reply from 209.249.181.23
Wed, 2013-11-13 20:24:02 - Router start up
Wed, 2013-11-13 20:36:59 - <TELNET> Administrator login successful - IP:192.168.0.2
Wed, 2013-11-13 20:38:07 - LCP down.
Wed, 2013-11-13 20:40:00 - Initialize LCP.
Wed, 2013-11-13 20:40:00 - LCP is allowed to come up.
Wed, 2013-11-13 20:40:01 - CHAP authentication success
Wed, 2013-11-13 20:40:29 - <NTP> Receive NTP Reply from 209.249.181.22
I have changed DSL Mode from Multi Mode to ADSL G.DMT. Modulation Mode is still on Multi Mode (there are three settings mentioning G.DMT). If I have Modulation Mode set wrong let me know! This accounts for the first dip in my RouterStats log.
I then changed the settings as suggested by ejs via telnet (which accounts for the second dip in my logs). The commands I entered, along with result, is as follows:
ben@reticle:~$ telnet 192.168.0.1
Trying 192.168.0.1...
Connected to 192.168.0.1.
Escape character is '^]'.
Login: admin
Password:

BusyBox v1.01 (2008.12.07-19:38+0000) Built-in shell (ash)
Enter 'help' for a list of built-in commands.
# rm /tmp/debug
# rc wan stop
ap_name=(null) action=stop
killall: keepalive: no process killed
iptables: Bad rule (does a matching rule exist in that chain?)
iptables: Bad rule (does a matching rule exist in that chain?)
iptables: Bad rule (does a matching rule exist in that chain?)
iptables: No chain/target/match by that name
interface nas0 does not exist!
killall: udhcpc: no process killed
killall: br2684ctl: no process killed
killall: atmarpd: no process killed
killall: pptp: no process killed
Using /lib/modules/2.4.17_mvl21-malta-mips_fp_le/kernel/net/ipv4/netfilter/ip_conntrack_sip.o
Using /lib/modules/2.4.17_mvl21-malta-mips_fp_le/kernel/net/ipv4/netfilter/ip_nat_sip.o
# echo idle > /proc/sys/dev/dslmod
# rmmod tiatm
# insmod tiatm
Using /lib/modules/2.4.17_mvl21-malta-mips_fp_le/kernel/drivers/atm/tiatm.o
# rc wan start
killall: pppoe-relay: no process killed
Plugin pppoa loaded.
PPPoA Plugin Initialized
Plugin pppoa called.
PPPoATM setdevname_pppoatm - SUCCESS
PPPoATM setdevname_pppoatm - SUCCESS
Options file - /etc/ppp/options.0.38.
setting line discipline hook
connect_pppoatm_ses...Enter
connect_pppoatm_ses: socket created fd - 0x6.
connect_pppoatm_ses: setsockopt called.
connect_pppoatm_ses: connect successful.
Calling line discipline hook
Setting pppoatm line discipline.
vc encaps.
Using interface ppp0
Connect: ppp0 <-->
Couldn't increase MTU to 32725
local  IP address 46.208.12.134
remote IP address 195.166.128.192
primary  DNS address 212.159.6.9
secondary DNS address 212.159.6.10
#
I am now logging once again. Attached is my first hour of logs along with statistics.
Anonymous
Not applicable

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Having switched from ADSL2 to ADSL1, but now seeing a download sync of 6784Kbps and a noise margin of 15dB,  does 'myredhotcar's line need an SNR reset to give it a fair chance to settle into G.DMT mode ?.  I would have thought that the noise margin should be nearer 12dB, and that being 15dB means it has it the end stop (so could be anywhere between 15dB and infinity).
Pettitto
Plusnet Alumni (retired)
Plusnet Alumni (retired)
Posts: 6,346
Fixes: 5
Registered: ‎26-11-2011

Re: Troubleshooting Psychosis: router LCP down, loss of sync

@purleigh
I would say so. DLM would reduce the SNRt eventually but could take a bit of time to reduce the SNRt to where we'd want it. I'll leave this overnight though to see how things have got on, if the line remains stable, I'll look at doing an SNR Reset and we can, at that point, see where we go from there.
ejs
Aspiring Hero
Posts: 5,442
Thanks: 631
Fixes: 25
Registered: ‎10-06-2010

Re: Troubleshooting Psychosis: router LCP down, loss of sync

"DSL Mode" and "Modulation Mode" set the same thing.
"DLM Mode" is in the standard firmware.
"Modulation Mode" is added by the dgteam firmware and has more values to choose from (most of which are of no use). But it could set ADSL2 (not 2+) by choosing G.DMT bis
I'm guessing you are using ADSL1 (G.DMT) based on the 448 upstream speed.
You need to get the more detailed stats from "cat /proc/avalanche/avsar_modem_stats" (and scrolling up). Particularly the CRC, FEC counts.
There's no "end stop" for the noise margin - if your line were banded, your noise margin could easily be say 20 dB. 15 dB is just the highest target snrm the DLM can set.
myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Thanks for the continuing support everyone  Smiley
AR7 DSL Modem Statistics:
--------------------------------
[DSL Modem Stats]
US Connection Rate: 448 DS Connection Rate: 6784
DS Line Attenuation: 37 DS Margin: 15
US Line Attenuation: 23 US Margin: 26
US Payload : 4207200 DS Payload: 16158288
US Superframe Cnt : 661182 DS Superframe Cnt: 661182
US Transmit Power : 0 DS Transmit Power: 0
LOS errors: 0 SEF errors: 0
Errored Seconds: 0 Severely Err Secs: 0
Frame mode: 3 Max Frame mode: 0
Trained Path: 1 US Peak Cell Rate: 1056
Trained Mode: 3 Selected Mode: 3
ATUC Vendor Code: 4946544E ATUC Revision: 1
Hybrid Selected: 1 Trellis: 1
Showtime Count: 1 DS Max Attainable Bit Rate: 6784 kbps
BitSwap: 1 US Max Attainable Bit Rate: n/a
Annex: AnxA psd_mask_qualifier: 0x0000
Power Management Status: L0 DS HLINSC: 0
US ACTPSD: -345 DS ACTPSD: -365
Total init. errors: 0 Total init. timeouts: 0
Showtime init. errors: 0 Showtime init. timeouts: 0
Last showtime init. errors: 0 Last showtime init. timeouts: 0
ATUC ghsVid:  b5 00 49 46 54 4e 71 c8
T1413Vid: 00 00 T1413Rev: 00 VendorRev: 00
ATUR ghsVid:  b5 00 54 53 54 43 00 00
T1413Vid: 00 00 T1413Rev: 00 VendorRev: 00
[Upstream (TX) Interleave path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0
[Downstream (RX) Interleave path]
CRC: 8 FEC: 1763 NCD: 0
LCD: 0 HEC: 0
[Upstream (TX) Fast path]
CRC: 0 FEC: 0 NCD: 1
LCD: 0 HEC: 0
[Downstream (RX) Fast path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0
[ATM Stats]
[Upstream/TX]
Good Cell Cnt: 87650
Idle Cell Cnt: 11788675
Tx Packets Dropped Count: 0
Tx Bad Packets Count: 0
[Downstream/RX)]
Good Cell Cnt: 336631
Idle Cell Cnt: 179504596
Bad Hec Cell Cnt: 139
Overflow Dropped Cell Cnt: 0
Rx Packets Dropped Count: 0
Rx Bad Packets Count: 0

[SAR AAL5 Stats]
Tx PDU's: 15983
Rx PDU's: 18171
Tx Total Bytes: 3565528
Rx Total Bytes: 15583005
Tx Total Error Counts: 0
Rx Total Error Counts: 0

[OAM Stats]
Near End F5 Loop Back Count: 0
Near End F4 Loop Back Count: 0
Far End F5 Loop Back Count: 0
Far End F4 Loop Back Count: 0
SAR OAM Ping Response Drop Count=0
myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Things have deteriorated  Shocked
In the early hours the DG834G reset and wouldn't play ball to the point where the internet was unusable and I had to plug the WBR-T2 in. That did the same thing for a short while but calmed down.
The internet is now painfully slow, I have attached a BT speedtest.
I will have to leave the WBR-T2 in until later today when I will try the netgear again.
ejs
Aspiring Hero
Posts: 5,442
Thanks: 631
Fixes: 25
Registered: ‎10-06-2010

Re: Troubleshooting Psychosis: router LCP down, loss of sync

"Trained mode: 3" indicates ADSL1.
ATUC Vendor Code: 4946544E = IFTN (Infineon, typical vendor for newer BT 21CN exchange equipment)
The change to report the figures to 0.1 dB has not worked (yet?). Can't really tell if average margin reporting was enabled but I'd guess not. The other way to check is:
1. echo dslctl > /proc/sys/dev/dslmod
2. dmesg

output ends with:
[tt]phy_feature_0=0x00004000, phy_cntl_mask_0=0x00004000
phy_feature_1=0x00000000, phy_cntl_mask_1=0x00000000[/tt]
If an adsl superframe is 17ms, those stats cover about 3 hours, and those CRC and FEC counts are tiny.
Anonymous
Not applicable

Re: Troubleshooting Psychosis: router LCP down, loss of sync

@'myredhotcar' - Did you go on to do the [Further Diagnostics] at the bottom of that BT performance test page.
By completing the [Further Diagnostics] test,  it provides additional information which is logged to Plusnet's fault reporting systems, and therefore will be useful for the faults engineers to have a look at snapshots of what happend at the times when you ran the test.
Pettitto
Plusnet Alumni (retired)
Plusnet Alumni (retired)
Posts: 6,346
Fixes: 5
Registered: ‎26-11-2011

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Could you complete the Broadband Fault Checker at http://faults.plus.net and I'll get that picked up for you once complete?
myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Hello all
I have been trying to run the tests to no avail. Pages are often not loading, or loading painfully slow. I will reattempt later on.
ejs
Aspiring Hero
Posts: 5,442
Thanks: 631
Fixes: 25
Registered: ‎10-06-2010

Re: Troubleshooting Psychosis: router LCP down, loss of sync

You could try setting the router to ADSL2 aka "G.DMT bis".
I'm guessing your line is so bad that no router will do any better.
myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Hi ejs
Things got unbearable with the Netgear so back on the WBR-T2, which appears to be doing better. I have also switched power adapters (just in case) and I am also connected to the test socket directly (i.e. without an ADSL splitter). From what I understand this is fine as I only have a single BT socket, so there are no other sockets with or without ADSL splitters. If my logic is flawed here I guess someone will let me know. The only issue is that if things drastically improve there are more variables what with the lack of splitter and a different cable (all of which I have tried before BTW).
@ purleigh
I ran the further diagnostics and have attached the results, will see how things go overnight.
@Chris Pettitt
I have no landline and cannot perform the line noise test but I am borrowing one tomorrow so will complete tests then.

Thanks everyone Smiley
Anonymous
Not applicable

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Quote from: myredhotcar
I am also connected to the test socket directly (i.e. without an ADSL splitter). From what I understand this is fine as I only have a single BT socket, so there are no other sockets with or without ADSL splitters. If my logic is flawed here I guess someone will let me know.

That is correct, you don't need filters fitted when the only device connected is your modem.  Smiley
myredhotcar
Grafter
Posts: 457
Registered: ‎06-11-2013

Re: Troubleshooting Psychosis: router LCP down, loss of sync

Morning everyone
The internet has been unbearably slow over the weekend with the WBR-T2 but I haven't noticed any flurries of disconnects so I am trying the Netgear to grab some stats. There is hopefully a Broadcom Netgear in the pipeline.
I also have some RouterStats grabs , BT speed test results, and other info from the house next door. When I say next door I mean literally too, and the house is closer to the exchange by a few meters. The router is a DG834G v3.
I am still trying to get a phone so I can proceed with the fault checker.
Cheers all.
ejs
Aspiring Hero
Posts: 5,442
Thanks: 631
Fixes: 25
Registered: ‎10-06-2010

Re: Troubleshooting Psychosis: router LCP down, loss of sync

It looks like the stats are being reported to 0.1dB rather than 1dB precision now.
Your slow speeds could be because Plusnet's copy of the IP profile is set too low from earlier: https://portal.plus.net/my.html?action=data_transfer_speed