cancel
Showing results for 
Search instead for 
Did you mean: 

Instability of 21CN and ADSL2+

penfold
Aspiring Pro
Posts: 2,280
Thanks: 25
Fixes: 5
Registered: ‎01-08-2007

Instability of 21CN and ADSL2+

I have posted in other threads regards this, but thought I would start my own.  I have concerns over the stability of 21CN, as I have previously mentioned, I can have 4-5days of an absolutely rock solid connection, with 6dB up/ 3dB down, then suddenly I start to resync all the time,until after 2-3 days, stability returns. Tonight rechecked logs, now at 424up/ 5663 down, and downstream margin now 7dB, upstream 15dB. Why is this happening. As I entered this trial with my eyes open knowing there cold be issues, I would be welcome to see what can be done about this, or is this a feature(flawed) of the 21CN DSLAMS.
69 REPLIES 69
James
Grafter
Posts: 21,036
Thanks: 5
Registered: ‎04-04-2007

Re: Instability of 21CN and ADSL2+

It is meant to stablise over time.  However, this can take a considerable period of time to find the optimal stability point with regards to noise margin and thus speed.
My ADSL2+ LLU line is a long way from being stable Smiley
jelv
Seasoned Hero
Posts: 26,785
Thanks: 971
Fixes: 10
Registered: ‎10-04-2007

Re: Instability of 21CN and ADSL2+

Quote from: Jameseh
My ADSL2+ LLU line is a long way from being stable Smiley

But does it instantly adapt to current line conditions (without the equivalent of IP Profile)?
jelv (a.k.a Spoon Whittler)
   Why I have left Plusnet (warning: long post!)   
Broadband: Andrews & Arnold Home::1 (FTTC 80/20)
Line rental: Pulse 8 Home Line Rental (£14.40/month)
Mobile: iD mobile (£4/month)
James
Grafter
Posts: 21,036
Thanks: 5
Registered: ‎04-04-2007

Re: Instability of 21CN and ADSL2+

Absolutely not.  My noise margin remains static unless I request a change.
It was fine @ 3dB.  then my line got noisier and would drop every 5 minutes.  Had to request an increase to 6dB and now it drops about 5 times a day.  I could request a few increase to improve stability if I could be bothered.
(I'm permanantly connected to the test socket which seems to offer a slightly better level of stability than the iplate.)
godsell4
Rising Star
Posts: 3,366
Thanks: 15
Registered: ‎06-04-2007

Re: Instability of 21CN and ADSL2+

But I think James is on Be/O2 LLU connection which is suspected to include SRA! So we expect his SNR to stay constant.
--
3Mb FTTC
https://portal.plus.net/my.html?action=data_transfer_speed
James
Grafter
Posts: 21,036
Thanks: 5
Registered: ‎04-04-2007

Re: Instability of 21CN and ADSL2+

Unlike my line stability Tongue
godsell4
Rising Star
Posts: 3,366
Thanks: 15
Registered: ‎06-04-2007

Re: Instability of 21CN and ADSL2+

But what are you observing/seeing to decide you line is unstable?
If you are getting constant SNR and seeing your line speed go up and down a bit, that is how SRA works.
--
3Mb FTTC
https://portal.plus.net/my.html?action=data_transfer_speed
James
Grafter
Posts: 21,036
Thanks: 5
Registered: ‎04-04-2007

Re: Instability of 21CN and ADSL2+

I'm talking about physical instability, not speed.
scootie
Grafter
Posts: 4,799
Thanks: 1
Registered: ‎03-11-2007

Re: Instability of 21CN and ADSL2+

Quote
then my line got noisier and would drop every 5 minutes

that would not stand up in court as being seamless.
beat me to it jimbo
penfold
Aspiring Pro
Posts: 2,280
Thanks: 25
Fixes: 5
Registered: ‎01-08-2007

Re: Instability of 21CN and ADSL2+

I have no issues regards the DSLAM trying to find stability, but surely 4-5 days rock solid with 3dB down/ 6dB up would be classified as stable.  I cant understand why I get these periods of terrible instability and continual resyncing.  Currently at 5888/601, with a Snr of 6/6.5  I really have no idea whats going on, and why I am continually resyncing. I am in the Master Filtered socket with a high quality RJ11 cable.
Current router logs look terrible
May 14 19:38:25 LOGOUT User logged out on TELNET (192.168.1.4)

Info May 14 19:37:33 LOGIN User logged in on TELNET (192.168.1.4)

Info May 14 19:01:37 FIREWALL event (1 of 1): deleted rules

Info May 14 19:01:37 GRP Default destination is routed via gateway 80.229.156.222

Warning May 14 19:01:37 PPP link up (Internet) [80.229.156.222]

Info May 14 19:01:37 PPP CHAP Chap receive success : authentication ok

Info May 14 19:01:37 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 14 19:01:37 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 14 19:01:29 xDSL linestate up (ITU-T G.992.5; downstream: 5888 kbit/s, upstream: 601 kbit/s; output Power Down: 20.0 dBm, Up: 13.0 dBm; line Attenuation Down: 44.5 dB, Up: 24.5 dB; snr Margin Down: 6.0 dB, Up: 6.5 dB)

Info May 14 19:01:05 xDSL linestate down

Info May 14 19:00:39 xDSL linestate down

Info May 14 19:00:25 xDSL linestate down

Info May 14 19:00:01 xDSL linestate up (ITU-T G.992.5; downstream: 5899 kbit/s, upstream: 718 kbit/s; output Power Down: 20.0 dBm, Up: 12.5 dBm; line Attenuation Down: 44.5 dB, Up: 24.5 dB; snr Margin Down: 6.0 dB, Up: 6.5 dB)

Warning May 14 19:00:00 PPP link down (Internet) [80.229.156.222]

Info May 14 18:59:35 xDSL linestate down

Info May 14 18:59:16 FIREWALL event (1 of 1): created rules

Info May 14 18:59:15 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 14 18:59:15 xDSL linestate down

Info May 14 18:58:40 FIREWALL event (1 of 1): deleted rules

Info May 14 18:58:40 GRP Default destination is routed via gateway 80.229.156.222

Warning May 14 18:58:40 PPP link up (Internet) [80.229.156.222]

Info May 14 18:58:40 PPP CHAP Chap receive success : authentication ok

Info May 14 18:58:39 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 14 18:58:39 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 14 18:58:28 xDSL linestate up (ITU-T G.992.5; downstream: 5942 kbit/s, upstream: 999 kbit/s; output Power Down: 20.0 dBm, Up: 12.5 dBm; line Attenuation Down: 44.0 dB, Up: 24.0 dB; snr Margin Down: 6.0 dB, Up: 6.5 dB)

Warning May 14 18:58:23 PPP link down (Internet) [80.229.156.222]

Info May 14 18:58:03 xDSL linestate down

Info May 14 18:57:37 FIREWALL event (1 of 1): created rules

Info May 14 18:57:38 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 14 18:57:38 xDSL linestate down

Info May 14 18:56:33 FIREWALL event (1 of 1): deleted rules

Info May 14 18:56:32 GRP Default destination is routed via gateway 80.229.156.222

Warning May 14 18:56:33 PPP link up (Internet) [80.229.156.222]

Info May 14 18:56:33 PPP CHAP Chap receive success : authentication ok

Info May 14 18:56:33 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 14 18:56:32 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 14 18:56:28 xDSL linestate up (ITU-T G.992.5; downstream: 4724 kbit/s, upstream: 89 kbit/s; output Power Down: 19.5 dBm, Up: 11.5 dBm; line Attenuation Down: 46.5 dB, Up: 26.0 dB; snr Margin Down: 6.0 dB, Up: 6.0 dB)

Warning May 14 18:56:04 PPP link down (Internet) [80.229.156.222]

Info May 14 18:56:02 xDSL linestate down
James
Grafter
Posts: 21,036
Thanks: 5
Registered: ‎04-04-2007

Re: Instability of 21CN and ADSL2+

Hi Penfold,
Have you tried raising a fault to the CSC?
Your connection shouldn't be seeing that level of instability, trial or no trial.
penfold
Aspiring Pro
Posts: 2,280
Thanks: 25
Fixes: 5
Registered: ‎01-08-2007

Re: Instability of 21CN and ADSL2+

Thanks James,  will do that now.  Currently at 5584/444  SNR Upstream now 25dB!!!!!!  Resynced just now, 5995/444.  I will raise a ticket for the attn of the 21CN team.
Thanks
Chris
penfold
Aspiring Pro
Posts: 2,280
Thanks: 25
Fixes: 5
Registered: ‎01-08-2007

Re: Instability of 21CN and ADSL2+

Logged this with support team now.  Odd thing today, againa few resyncs, but as seen in the logs below, one resync suddenly had both up and down SNR at 6dB, and the immediate resyncs before and after up is again at 24dB. I personally feel there is some fault at the exchange on my line, as my setup is unchanged, since the absolute stability of 20CN. Any ideas anyone?
May 16 18:43:19 SNTP Synchronised to server: 212.159.13.49

Info May 16 17:43:19 SNTP Synchronised again to server: 212.159.6.9

Info May 16 16:43:19 SNTP Synchronised to server: 212.159.6.9

Error May 16 16:29:10 FIREWALL icmp check (1 of 1): Protocol: ICMP Src ip: 216.114.66.158 Dst ip: 80.229.156.222 Type: Destination Unreachable Code: Host Unreacheable

Info May 16 15:43:18 SNTP Synchronised to server: 212.159.13.49

Info May 16 14:43:19 SNTP Synchronised to server: 212.159.6.10

Info May 16 13:43:20 SNTP Synchronised to server: 212.159.13.49

Info May 16 13:43:08 FIREWALL event (1 of 1): deleted rules

Info May 16 13:43:08 GRP Default destination is routed via gateway 80.229.156.222

Warning May 16 13:43:08 PPP link up (Internet) [80.229.156.222]

Info May 16 13:43:08 PPP CHAP Chap receive success : authentication ok

Info May 16 13:43:08 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 16 13:42:52 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 16 13:42:42 xDSL linestate up (ITU-T G.992.5; downstream: 5596 kbit/s, upstream: 471 kbit/s; output Power Down: 20.0 dBm, Up: 13.0 dBm; line Attenuation Down: 44.5 dB, Up: 24.5 dB; snr Margin Down: 6.0 dB, Up: 6.5 dB)

Warning May 16 13:42:35 PPP link down (Internet) [80.229.156.222]

Info May 16 13:42:17 xDSL linestate down

Info May 16 13:41:56 FIREWALL event (1 of 1): created rules

Info May 16 13:41:55 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 16 13:41:55 xDSL linestate down

Info May 16 12:45:02 FIREWALL event (1 of 1): deleted rules

Info May 16 12:45:02 GRP Default destination is routed via gateway 80.229.156.222

Warning May 16 12:45:02 PPP link up (Internet) [80.229.156.222]

Info May 16 12:45:02 PPP CHAP Chap receive success : authentication ok

Info May 16 12:45:02 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 16 12:45:02 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 16 12:44:51 xDSL linestate up (ITU-T G.992.5; downstream: 5998 kbit/s, upstream: 952 kbit/s; output Power Down: 20.0 dBm, Up: 13.0 dBm; line Attenuation Down: 44.5 dB, Up: 24.0 dB; snr Margin Down: 6.0 dB, Up: 6.5 dB)

Warning May 16 12:44:45 PPP link down (Internet) [80.229.156.222]

Info May 16 12:44:26 xDSL linestate down

Info May 16 12:44:01 FIREWALL event (1 of 1): created rules

Info May 16 12:44:01 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 16 12:44:01 xDSL linestate down

Info May 16 12:43:14 SNTP Synchronised to server: 212.159.6.9

Info May 16 12:20:55 FIREWALL event (1 of 1): deleted rules

Info May 16 12:20:54 GRP Default destination is routed via gateway 80.229.156.222

Warning May 16 12:20:55 PPP link up (Internet) [80.229.156.222]

Info May 16 12:20:55 PPP CHAP Chap receive success : authentication ok

Info May 16 12:20:54 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 16 12:20:53 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 16 12:20:42 xDSL linestate up (ITU-T G.992.5; downstream: 5923 kbit/s, upstream: 197 kbit/s; output Power Down: 20.0 dBm, Up: 11.0 dBm; line Attenuation Down: 44.5 dB, Up: 24.5 dB; snr Margin Down: 6.0 dB, Up: 7.5 dB)
spraxyt
Resting Legend
Posts: 10,063
Thanks: 674
Fixes: 75
Registered: ‎06-04-2007

Re: Instability of 21CN and ADSL2+

Quote from: penfold
Odd thing today, again a few resyncs, but as seen in the logs below, one re-sync suddenly had both up and down SNR at 6dB, and the immediate re-syncs before and after up is again at 24dB.
Info May 16 13:42:42 xDSL linestate up (ITU-T G.992.5;
downstream: 5596 kbit/s, upstream: 471 kbit/s;
output Power Down: 20.0 dBm, Up: 13.0 dBm;
line Attenuation Down: 44.5 dB, Up: 24.5 dB;
snr Margin Down: 6.0 dB, Up: 6.5 dB)
Info May 16 12:44:51 xDSL linestate up (ITU-T G.992.5;
downstream: 5998 kbit/s, upstream: 952 kbit/s;
output Power Down: 20.0 dBm, Up: 13.0 dBm;
line Attenuation Down: 44.5 dB, Up: 24.0 dB;
snr Margin Down: 6.0 dB, Up: 6.5 dB)
Info May 16 12:20:42 xDSL linestate up (ITU-T G.992.5;
downstream: 5923 kbit/s, upstream: 197 kbit/s;
output Power Down: 20.0 dBm, Up: 11.0 dBm;
line Attenuation Down: 44.5 dB, Up: 24.5 dB;
snr Margin Down: 6.0 dB, Up: 7.5 dB)

I think there was some misreading there, the SNR Margins in order are shown as
(Down/Up)  (6.0/7.5 dB), (6.0/6.5 dB) and (6.0/6.5 dB again).
Obviously a fault somewhere, hope it is found and fixed this time rather than just lying low again.
David
David
penfold
Aspiring Pro
Posts: 2,280
Thanks: 25
Fixes: 5
Registered: ‎01-08-2007

Re: Instability of 21CN and ADSL2+

Thanks David,  think my eyesights probably going Crazy
Passed all this through to Faults, they say they can find no fault, even though all their tests show as intermittant. Sync is still as random as was, also noticed, that the router does take a hell of a long time to obtain sync, flashes like crazy for around 15secs  then stops, does this another couple of times, and then gets sync, sometimes PPP session dosnt even get a chance to start before sync is lost.  I attached another set of router stats, upstream now a pathetic 200odd......  Obviously something amiss, but I will jump through the hoops again. Will attach my older trusty Speedtouch 585V6, and see what happens.  Can anyone suggest anything else??  I also nothiced some firewall blocks over the last couple of days, could this be Plus trying to access my router??  Also how do I use router stats, as I think I need to monitor the SNR....
May 18 19:03:40 FIREWALL event (1 of 2): deleted rules

Warning May 18 19:03:40 PPP link up (Internet) [80.229.156.222]

Info May 18 19:03:40 GRP Default destination is routed via gateway 80.229.156.222

Info May 18 19:03:41 PPP CHAP Chap receive success : authentication ok

Info May 18 19:03:40 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 18 19:03:40 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 18 19:03:39 xDSL linestate up (ITU-T G.992.5; downstream: 5725 kbit/s, upstream: 275 kbit/s; output Power Down: 20.0 dBm, Up: 10.0 dBm; line Attenuation Down: 44.5 dB, Up: 24.0 dB; snr Margin Down: 6.5 dB, Up: 7.5 dB)

Info May 18 19:03:13 xDSL linestate down

Info May 18 19:02:47 xDSL linestate down

Info May 18 19:02:27 xDSL linestate down

Info May 18 19:02:11 xDSL linestate up (ITU-T G.992.5; downstream: 4814 kbit/s, upstream: 90 kbit/s; output Power Down: 19.5 dBm, Up: 12.0 dBm; line Attenuation Down: 46.0 dB, Up: 26.0 dB; snr Margin Down: 6.0 dB, Up: 6.0 dB)

Info May 18 19:01:45 xDSL linestate down

Info May 18 19:01:21 xDSL linestate down

Warning May 18 19:01:13 PPP link down (Internet) [80.229.156.222]

Info May 18 19:00:55 xDSL linestate down

Info May 18 19:00:35 FIREWALL event (1 of 2): created rules

Info May 18 19:00:35 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 18 19:00:35 xDSL linestate down

Warning May 18 18:59:45 SNTP Roundtrip exceeds limits

Error May 18 18:30:04 FIREWALL icmp check (1 of 1): Protocol: ICMP Src ip: 202.125.38.25 Dst ip: 80.229.156.222 Type: Destination Unreachable Code: Port Unreacheable

Info May 18 17:59:35 SNTP Synchronised again to server: 212.159.6.10

Info May 18 16:59:34 SNTP Synchronised to server: 212.159.6.10

Info May 18 15:59:34 SNTP Synchronised to server: 212.159.13.50

Info May 18 14:59:35 SNTP Synchronised to server: 212.159.6.10

Info May 18 14:56:08 GRP Default destination is routed via gateway 80.229.156.222

Warning May 18 14:56:08 PPP link up (Internet) [80.229.156.222]

Info May 18 14:56:08 PPP CHAP Chap receive success : authentication ok

Info May 18 14:56:08 PPP CHAP Receive challenge (rhost = THN-AG2)

Info May 18 14:56:08 PPP CHAP Receive challenge (rhost = bras-red1.pr)

Info May 18 14:55:12 GRP Default destination is not routed anymore via gateway 80.229.156.222

Warning May 18 14:55:12 PPP link down (Internet) [80.229.156.222]

Info May 18 14:55:11 FIREWALL event (1 of 1): deleted rules

Info May 18 14:55:11 GRP Default destination is routed via gateway 80.229.156.222

Info May 18 14:55:10 xDSL linestate up (ITU-T G.992.5; downstream: 5881 kbit/s, upstream: 491 kbit/s; output Power Down: 20.0 dBm, Up: 12.5 dBm; line Attenuation Down: 44.5 dB, Up: 24.5 dB; snr Margin Down: 6.0 dB, Up: 6.0 dB)

Info May 18 14:54:46 xDSL linestate down

Info May 18 14:54:26 FIREWALL event (1 of 1): created rules

Info May 18 14:54:26 GRP Default destination is not routed anymore via gateway 80.229.156.222

Info May 18 14:54:26 xDSL linestate down

Info May 18 14:50:52 FIREWALL event (1 of 1): deleted rules


Pick a task...