ADSL link down

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Carrot Cruncher
Posts: 28
Joined: Sun Nov 04, 2012 9:42 am

ADSL link down

Post by Carrot Cruncher »

hi. my 7800, which is normally up, and stable, 24x7 has been dropping out all day today :

Code: Select all

Nov 14 12:15:47 router   router kernel: Line 0: ADSL link down
Nov 14 12:16:09 router   router kernel: Line 0: ADSL link down
Nov 14 12:23:59 router   router kernel: Line 0: ADSL link down
Nov 14 12:24:22 router   router kernel: Line 0: ADSL link down
Nov 14 12:30:35 router   router kernel: Line 0: ADSL link down
Nov 14 12:30:58 router   router kernel: Line 0: ADSL link down
Nov 14 16:01:05 router   router kernel: Line 0: ADSL link down
Nov 14 16:01:27 router   router kernel: Line 0: ADSL link down
Nov 14 16:02:09 router   router kernel: Line 0: ADSL link down
Nov 14 16:02:31 router   router kernel: Line 0: ADSL link down
Nov 14 16:59:13 router   router kernel: Line 0: ADSL link down
Nov 14 16:59:35 router   router kernel: Line 0: ADSL link down
Nov 14 17:23:57 router   router kernel: Line 0: ADSL link down
Nov 14 17:24:29 router   router kernel: Line 0: ADSL link down
Nov 14 17:25:56 router   router kernel: Line 0: ADSL link down
Nov 14 17:26:18 router   router kernel: Line 0: ADSL link down
Nov 14 17:29:22 router   router kernel: Line 0: ADSL link down
Nov 14 17:29:45 router   router kernel: Line 0: ADSL link down
Nov 14 17:33:58 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:21 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:35 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:50 router   router kernel: Line 0: ADSL link down
Nov 14 17:51:26 router   router kernel: Line 0: ADSL link down
Nov 14 17:51:49 router   router kernel: Line 0: ADSL link down
Nov 14 17:53:15 router   router kernel: Line 0: ADSL link down
Nov 14 17:53:38 router   router kernel: Line 0: ADSL link down
Nov 14 17:55:06 router   router kernel: Line 0: ADSL link down
Nov 14 17:55:29 router   router kernel: Line 0: ADSL link down
Nov 14 17:56:30 router   router kernel: Line 0: ADSL link down
Nov 14 17:56:53 router   router kernel: Line 0: ADSL link down
Nov 14 17:58:06 router   router kernel: Line 0: ADSL link down
Nov 14 17:58:29 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:03 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:25 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link down
the looping message in the log is :

Code: Select all

Nov 14 18:00:03 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:03 router   router udhcpc: Broadcast a release
Nov 14 18:00:03 router   router udhcpc: Sending release...
Nov 14 18:00:03 router   router udhcpc: Entering released state
Nov 14 18:00:04 router   router kernel: Line 0: xDSL G.994 training
Nov 14 18:00:14 router   router kernel: Line 0: ADSL G.992 started
Nov 14 18:00:18 router   router kernel: Line 0: ADSL G.992 channel analysis
Nov 14 18:00:24 router   router kernel: Line 0: ADSL G.992 message exchange
Nov 14 18:00:25 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:26 router   router kernel: Line 0: xDSL G.994 training
Nov 14 18:00:36 router   router kernel: Line 0: ADSL G.992 started
Nov 14 18:00:40 router   router kernel: Line 0: ADSL G.992 channel analysis
Nov 14 18:00:46 router   router kernel: Line 0: ADSL G.992 message exchange
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link up, Path 0, us=773, ds=5023
Nov 14 18:00:48 router   router udhcpc: Performing a DHCP renew
Nov 14 18:00:48 router   router udhcpc: Sending discover...
Nov 14 18:00:48 router   router syslog: dhcpc -i nas_0_0_40 -D 1 -N 1 -T 1 -c "{mac address}@skydsl|{password}"
Nov 14 18:00:48 router   router udhcpc: Sending discover...
Nov 14 18:00:48 router   router udhcpc: Sending select for 94.3.16.142...
Nov 14 18:00:48 router   router udhcpc: Sending select for 94.3.16.142...
Nov 14 18:00:48 router   router udhcpc: Lease of 94.3.16.142 obtained, lease time 3572
Nov 14 18:00:48 router   router udhcpc: Lease of 94.3.16.142 obtained, lease time 3630
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.99#53
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.97#53
Nov 14 18:00:49 router   router syslog: begin: interface: nas_0_0_40 go to up 
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.99#53
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.97#53
Nov 14 18:00:49 router   router UPNPD[7637]: received signal 15, good-bye
Nov 14 18:00:52 router   router UPNPD[10403]: uuidvalue=uuid:c8cd7294-bb1e-c8cd-7294-bb1e0000900
Nov 14 18:00:52 router   router UPNPD[10403]: HTTP listening on port 2800
Nov 14 18:00:54 router   router syslog: end: interface: nas_0_0_40 go to up 
Nov 14 18:00:55 router   router syslog: wan6Autod start..
Nov 14 18:01:35 router   router syslog: dhcp6c restart..
the adsl settings are :
ADSL Mode Annex L Annex M
Modulator ADSL2 ADSL2+ G.Lite T1.413 G.Dmt
Capability off
PhyR both off

the adsl status is :
DSP Firmware Version A2pB025f.d22k
DMT Status No Defect
Operational Mode ADSL2+
Upstream 773
Downstream 5023
SNR Margin(Upstream) 9.7
SNR Margin(Downstream) 6.4
Line Attenuation(Upstream) 31.4
Line Attenuation(Downstream) 52.0

before i have, what i'm assuming will be, a pointless conversation with my isp (sky). does anyone know what the cause could be or how i can debug this further ? cheers.
Tomken
Posts: 467
Joined: Tue Jul 26, 2011 10:31 am
Location: Co Durham

Re: ADSL link down

Post by Tomken »

I'm not into Sky, but I always thought that it was either Annex L or Annex M and not both enabled.

When ADSL gets buggy on a longish line, then changing the Mode to just G.Dmt can help.

Is this a wireless problem or wired as well ?

If it's just wireless then perhaps a channel change would help.

Download this program http://www.metageek.net/products/inssider/ and it will show if there are any other users on the same channel or either side of you and with a RSSI value within -20dBm of your value.

Any nearby users whose value exceeds that will not cause any conflict with you.

These may be new users and as channels 1, 6 and 11 are usually the most used because they don't overlap, then one or more could be causing the conflict that's giving you the disconnects.

You should be looking for a channel that gives you a RSSI value of ~ -50dB or less - up to -70dBm is considered the max for connectivity (60 - 70 is still considered as a weak signal), but anything greater than that and you're in disconnect territory - disregard the minus value as a mathematical value for comparison purposes.

Do you have a test socket that you could plug into to determine if the problem is on your end or their's and a change of microfilter could also help.
billion_fan
Posts: 5398
Joined: Tue Jul 19, 2011 4:30 pm

Re: ADSL link down

Post by billion_fan »

Carrot Cruncher wrote:hi. my 7800, which is normally up, and stable, 24x7 has been dropping out all day today :

Code: Select all

Nov 14 12:15:47 router   router kernel: Line 0: ADSL link down
Nov 14 12:16:09 router   router kernel: Line 0: ADSL link down
Nov 14 12:23:59 router   router kernel: Line 0: ADSL link down
Nov 14 12:24:22 router   router kernel: Line 0: ADSL link down
Nov 14 12:30:35 router   router kernel: Line 0: ADSL link down
Nov 14 12:30:58 router   router kernel: Line 0: ADSL link down
Nov 14 16:01:05 router   router kernel: Line 0: ADSL link down
Nov 14 16:01:27 router   router kernel: Line 0: ADSL link down
Nov 14 16:02:09 router   router kernel: Line 0: ADSL link down
Nov 14 16:02:31 router   router kernel: Line 0: ADSL link down
Nov 14 16:59:13 router   router kernel: Line 0: ADSL link down
Nov 14 16:59:35 router   router kernel: Line 0: ADSL link down
Nov 14 17:23:57 router   router kernel: Line 0: ADSL link down
Nov 14 17:24:29 router   router kernel: Line 0: ADSL link down
Nov 14 17:25:56 router   router kernel: Line 0: ADSL link down
Nov 14 17:26:18 router   router kernel: Line 0: ADSL link down
Nov 14 17:29:22 router   router kernel: Line 0: ADSL link down
Nov 14 17:29:45 router   router kernel: Line 0: ADSL link down
Nov 14 17:33:58 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:21 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:35 router   router kernel: Line 0: ADSL link down
Nov 14 17:34:50 router   router kernel: Line 0: ADSL link down
Nov 14 17:51:26 router   router kernel: Line 0: ADSL link down
Nov 14 17:51:49 router   router kernel: Line 0: ADSL link down
Nov 14 17:53:15 router   router kernel: Line 0: ADSL link down
Nov 14 17:53:38 router   router kernel: Line 0: ADSL link down
Nov 14 17:55:06 router   router kernel: Line 0: ADSL link down
Nov 14 17:55:29 router   router kernel: Line 0: ADSL link down
Nov 14 17:56:30 router   router kernel: Line 0: ADSL link down
Nov 14 17:56:53 router   router kernel: Line 0: ADSL link down
Nov 14 17:58:06 router   router kernel: Line 0: ADSL link down
Nov 14 17:58:29 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:03 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:25 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link down
the looping message in the log is :

Code: Select all

Nov 14 18:00:03 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:03 router   router udhcpc: Broadcast a release
Nov 14 18:00:03 router   router udhcpc: Sending release...
Nov 14 18:00:03 router   router udhcpc: Entering released state
Nov 14 18:00:04 router   router kernel: Line 0: xDSL G.994 training
Nov 14 18:00:14 router   router kernel: Line 0: ADSL G.992 started
Nov 14 18:00:18 router   router kernel: Line 0: ADSL G.992 channel analysis
Nov 14 18:00:24 router   router kernel: Line 0: ADSL G.992 message exchange
Nov 14 18:00:25 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:26 router   router kernel: Line 0: xDSL G.994 training
Nov 14 18:00:36 router   router kernel: Line 0: ADSL G.992 started
Nov 14 18:00:40 router   router kernel: Line 0: ADSL G.992 channel analysis
Nov 14 18:00:46 router   router kernel: Line 0: ADSL G.992 message exchange
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link down
Nov 14 18:00:47 router   router kernel: Line 0: ADSL link up, Path 0, us=773, ds=5023
Nov 14 18:00:48 router   router udhcpc: Performing a DHCP renew
Nov 14 18:00:48 router   router udhcpc: Sending discover...
Nov 14 18:00:48 router   router syslog: dhcpc -i nas_0_0_40 -D 1 -N 1 -T 1 -c "{mac address}@skydsl|{password}"
Nov 14 18:00:48 router   router udhcpc: Sending discover...
Nov 14 18:00:48 router   router udhcpc: Sending select for 94.3.16.142...
Nov 14 18:00:48 router   router udhcpc: Sending select for 94.3.16.142...
Nov 14 18:00:48 router   router udhcpc: Lease of 94.3.16.142 obtained, lease time 3572
Nov 14 18:00:48 router   router udhcpc: Lease of 94.3.16.142 obtained, lease time 3630
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.99#53
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.97#53
Nov 14 18:00:49 router   router syslog: begin: interface: nas_0_0_40 go to up 
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.99#53
Nov 14 18:00:49 router   router dnsmasq[64]: using nameserver 90.207.238.97#53
Nov 14 18:00:49 router   router UPNPD[7637]: received signal 15, good-bye
Nov 14 18:00:52 router   router UPNPD[10403]: uuidvalue=uuid:c8cd7294-bb1e-c8cd-7294-bb1e0000900
Nov 14 18:00:52 router   router UPNPD[10403]: HTTP listening on port 2800
Nov 14 18:00:54 router   router syslog: end: interface: nas_0_0_40 go to up 
Nov 14 18:00:55 router   router syslog: wan6Autod start..
Nov 14 18:01:35 router   router syslog: dhcp6c restart..
the adsl settings are :
ADSL Mode Annex L Annex M
Modulator ADSL2 ADSL2+ G.Lite T1.413 G.Dmt
Capability off
PhyR both off

the adsl status is :
DSP Firmware Version A2pB025f.d22k
DMT Status No Defect
Operational Mode ADSL2+
Upstream 773
Downstream 5023
SNR Margin(Upstream) 9.7
SNR Margin(Downstream) 6.4
Line Attenuation(Upstream) 31.4
Line Attenuation(Downstream) 52.0

before i have, what i'm assuming will be, a pointless conversation with my isp (sky). does anyone know what the cause could be or how i can debug this further ? cheers.

Have you tired to higher your SNR via the hidden page http://192.168.1.254/snr.html and once on this page change the SNR value to 150, this settings should higher your SNR and hopefully give you a more stable connection
Carrot Cruncher
Posts: 28
Joined: Sun Nov 04, 2012 9:42 am

Re: ADSL link down

Post by Carrot Cruncher »

thanks for the responses. i haven't tried changing the snr yet but i've tried a combination of the "adsl mode" and modulator settings all with differing results. i'm currently back on my sky router which is stable. i asked my isp what adsl annex/standard they were using and they couldn't tell me. are these settings on the router effectively forcing settings irrespective of what it would get when it syncs ? i.e. should my starting point be with all the options unchecked on this page ?
Carrot Cruncher
Posts: 28
Joined: Sun Nov 04, 2012 9:42 am

Re: ADSL link down

Post by Carrot Cruncher »

having done some more searching around, particularly on the skyuser forums, it would appear that sky only uses "annex a" in the uk so i unchecked both "annex l" and "annex m". with these both unchecked i then tried each of the modulator options in turn, the results were :

ADSL2 - keeps trying to bring the adsl link up but fails.
ADSL2+ - keeps trying to bring the adsl link up but fails.
G.Lite - keeps trying to bring the adsl link up but fails.
T1.413 - doesn't try to bring the adsl link up.
G.Dmt - brings the adsl link up successfully and (so far) the connection has been stable.

no idea if i should be enabling sra and/or phyr, have left them all unchecked.

i'm a long way away from the exchange so i'm not expecting the quality/speed to be great, i'm just after stability.

so, does anyone know, are the settings on this config page forcing a setting or simply enabling it if the line supports it ? eg. should i check "annex m" just in case sky choose to implement this at some point in the future, or should i stick with what works now and only change the settings if it stops working or i am advised that different/new technology is being used by my isp ? cheers.
tinytim
Posts: 218
Joined: Sun Aug 14, 2011 4:53 pm
Location: Benfleet, Essex

Re: ADSL link down

Post by tinytim »

Quite honestly the first thing to do is connect your Sky router & see what that does.

If that works it's a Billion problem & therefore no point talking to Sky , otherwise if the problem persists with the Sky router then call Sky.

Just read your last post more thoroughly and I think checking some of these settings will only have effect if the ISP supports them.

I'm on Sky & do have Annex M checked , no sure why really to be honest. Also SRA is checked and I only check the ADSL2/2+ modes as that's all I want to connect at.

In your case checking only the G.dMT is probably the right thing to do as ADSL(G.dMT) on a long line should be more stable and potentially give you a higher speed.
Carrot Cruncher
Posts: 28
Joined: Sun Nov 04, 2012 9:42 am

Re: ADSL link down

Post by Carrot Cruncher »

i've got two sky routers but the firmware on them is so locked down that it's impossible to work out how they are connecting. from further reading of forums i understand that sky only use "annex a" and either adsl2+ or adsl (g.dmt). i've also read that g.dmt is generally better for longer lines. i'm now back up on my 7800 using adsl2+ (don't know why it wouldn't work earlier). if i get any problems i'll restrict the router to using g.dmt and/or up the snr and see what happens (which were the original suggestions :oops: ) have learnt a lot about adsl as a result of this issue :) . thanks for all the responses.
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