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Unreliable ADSL2+ Connection

FIXED
Seasoned Hero
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Re: Unreliable ADSL2+ Connection

@archerry Alistair, have you had any response to the ticket? I assume you aren't/haven't been using the phone this early in the morning?

 

EDIT to add: that looks amazingly like my RS graphs before they changed the frame at the local exchange for me.

John
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Re: Unreliable ADSL2+ Connection

I still have had no response to my request to escalate this issue.

After the last Openreach visit I have heard nothing from Plusnet despite asking for further help and providing additional detail.
The connection is currently almost stable but slow and very laggy.
The root cause has not been identified (or least not acknowledged) after first raising the issue in late July (current ticket opened 30 Sept).
What do these last two entries on the ticket mean?
' [Name] - CSC Analyst
' 8:55am, Monday 7 Dec 2020
' -internal-
'
' customer called in chasing on any update after engineer visit.
'
' customer still getting a dropping connection on the line and also sent us in attachment with more details on regarding the issue.
'
' Kind regards,
'
' [Name]
'
' [Name] - CSC Analyst
' 9:59am, Tuesday 8 Dec 2020
' Dear Mr Cherry,
'
' **INTERNAL**
'
' Passing as previous agent already actioned.
'
' Kind regards,
'
' [Name]

We are trying to work and study at home and are dependent on this service.
The attached files show that connection is both slow and unreliable.
What is being done to resolve the root cause?

Regards,
Alistair

Seasoned Hero
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Re: Unreliable ADSL2+ Connection

@archerry I have kind of lost track on this topic, but what did the last engineer say as regards the problem, if anything?

Are those choppy graphs connected with either incoming or outgoing calls?

What does the QLT sound like during those periods?

John
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Re: Unreliable ADSL2+ Connection

@jab1 Following your suggestion a few posts back, I posted on the open ticket asking for an escalation to the "Specialist Faults Investigator" but have had no response from Plusnet.

On the last visit Openreach changed a short (~3m) length of cable between the master socket and the 'drop line' and reported NFF.

A short time ago, I took a call on the landline which just about coincided with a loss of connection, and the line was noisy during the call. Immediately after the call I checked the SNR Margin trace and saw that the uptime was ~19min, the call lasted ~20:41 minutes which to me is too much of a coincidence, suggesting that they are directly related.

After the call the QLT was still noisy.

Attached are the SNR Margin trace and the log file.

 

Regards,

Alistair

Edit: After the last Openreach visit, there has been no report/comment added to the open ticket.

Seasoned Hero
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Re: Unreliable ADSL2+ Connection

Alistair, you need the SFI engineer. I still think from your last post (and previous) that there is a fault on the exchange equipment, and this needs tracing by a suitably qualified individual.

Unfortunately, Plusnet, for whatever reason, seem reluctant to help their customers these days, but there is sufficient detail in this thread and on the ticket, I would imagine, to show any reasonably competent individual that you have a major problem, which is not resolved.

Sorry I can't be of any real help.

 

EDIT: Your edit doesn't surprise me in the slightest.

John
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Re: Unreliable ADSL2+ Connection

Plusnet staff,

Please reopen my helpdesk question (N0. 206678774).

It appears to have closed while I was responding to a CSC Analyst who wanted me to repeat all the MasterSocket and QLT actions I have been doing for over three months.

Regards,

Alistair

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Re: Unreliable ADSL2+ Connection

After calling the helpdesk, the question has been re-opened. Thank you.

A "Senior Engineer / Multi-skilled Engineer" is booked for Friday AM (18 Dec).

"REIN Investigation" and "Lift-and-Shift" were both mentioned.

Hope springs eternal for a stable responsive connection...

Regards,

Alistair

Seasoned Hero
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Re: Unreliable ADSL2+ Connection

Sounds like you're getting somewhere. Hope you see the engineer before he starts work - I personally don't think REIN is involved, but it is worth checking. My money is still on an exchange problem - which a 'lift-and-shift' should hopefully solve, but I suggest if he is an amenable guy you mention a 'frame' investigation - my 'lift and shift' was insufficient to resolve the problem.

John
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Re: Unreliable ADSL2+ Connection

Thanks John, I will try to remember that keyword.
I think that the fault is getting less intermittent and tending towards a hard fail:
An incoming at 10:56 (given by the 1471 service) caused a DSL connection drop this morning.
The RouterStatsHub5 log shows the connection ok at 10:56:22, but down at 10:56:52 and 10:57:22.
As previously reported, the same happened yesterday when I took a call.

Regards,

Alistair

Superuser
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Re: Unreliable ADSL2+ Connection

The SNRM plots are just plain ugly!

@Gandalf are there any updates here please?

Rising Star
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Re: Unreliable ADSL2+ Connection

Fix

@Townman 

Tell me, we woke up to 2.5Mb/s download today.

The good news:

The Openreach 'Multi-Discipline Engineer' was here this morning...
The isolation of the twisted pair to the exchange was marginal;
testing the lines on the telegraph pole behind us, the available odd-numbered pairs were marginal, the even-numbered were good;
the connection to the exchange was moved to one of the 'good' ones;
after visiting the exchange, the connection performed much better.
It was stated that a 'lift-and-shift' would not be granted if requested as the frame was giving 22Mb/s download.

The SNR Margin trace is almost rock steady, wavering about the thickness of the line on the chart.

Below is output from the Plusnet Hub One helpdesk page:
1. Product name: Plusnet Hub
4. Board version: Plusnet Hub One
5. DSL uptime: 0 days, 01:50:20
6. Data rate: 888 / 17414
7. Maximum data rate: 888 / 17536
8. Noise margin: 11.7 / 15.3
9. Line attenuation: 5.9 / 12.2
10. Signal attenuation: 5.8 / 10.3
11. Data sent/received: 3.2 GB / 38.4 GB
23. VPI/VCI: 0 / 38
24. Modulation: G.992.5 Annex A
25. Latency type: Interleaved

What happens now?
Do we reset the connection and try fastpath?
When will this happen?

Regards,
Alistair

Seasoned Hero
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Re: Unreliable ADSL2+ Connection

Alistair, the only 'disturbing' figures in there are Line 8 - Noise margin, which look high to me, otherwise all good.

I think I'll leave further comment to @Townman - he has more experience on this than I have, despite my fun and games last year.Smiley

John
Superuser
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Re: Unreliable ADSL2+ Connection

The identification of a highly suspect e-side is great news, but one does wonder why the previous engineers did not identify this issue?  One also wonders why the engineer did not do a DLSM reset?

It is now down to @Gandalf or another on the team to pick up the baton to do a line reset.  It would be worth while you updating your ticket with the new from the engineer visit and request a line rest, without any restrictions to see what the line is now capable of.

Superuser
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Re: Unreliable ADSL2+ Connection

Hi John,

It is easy enough really...

  1. SNRM (and stability) and speed (and error rates) have an inverse relationship
  2. SNRM goes up, stability goes up, speed goes down, error rates go down
  3. SNRM goes down, stability goes down, speed goes up, error rate go up
  4. Ideally DS SNRM should be around 6dB, good lines will tolerate 3dB, marginal lines might need 9dB anything outside of those figures point to issues ... unless on a very short line
  5. Which is where attenuation comes in - that is the figure which determines the expected speed at 6dB

On a very short line, one might see the maximum speed with lots of SNRM 'headroom' in which case a SNMR above 9dB is quite acceptable.  See kitz.co.uk for the chapter and verse on all of this stuff.

Seasoned Hero
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Registered: ‎24-02-2012

Re: Unreliable ADSL2+ Connection

Thanks @Townman . I'll try and remember that for future reference, but the number of unused brain cells is reducing.Smiley

John