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[albert]

Hello,

On a VDSL line, is it normal for the connection to drop about every 7 days? It does seem to happen in the early morning.

During this time my router is logging an outage and failing over to 4G so it is down for a minute.

Using an HG612.ß

Thanks

[tubaman]

No it's not normal, but with your screenshot showing 330 ES per hour I'm surprised it isn't dropping rather more often than that. I'm also surprised that it's holding 3dB on the downstream as I'd expect DLM to have intervened with such high ES numbers.
As you are using an HG612 it'd be worth getting the line stats from the telnet interface to confirm them as I believe the ones in the GUI can be suspect.

[albert]

No it's not normal, but with your screenshot showing 330 ES per hour I'm surprised it isn't dropping rather more often than that. I'm also surprised that it's holding 3dB on the downstream as I'd expect DLM to have intervened with such high ES numbers.
As you are using an HG612 it'd be worth getting the line stats from the telnet interface to confirm them as I believe the ones in the GUI can be suspect.

Hm ok thanks for your response!

I'm not familiar with the ES, what would you expect it to be?

Code: [Select]

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 1
Last initialization procedure status: 0
Max: Upstream rate = 12512 Kbps, Downstream rate = 65132 Kbps
Bearer: 0, Upstream rate = 12679 Kbps, Downstream rate = 66348 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3959)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2776)
DS: (33,859) (1216,1961) (2793,3959)
  VDSL Port Details   Upstream   Downstream
Attainable Net Data Rate:     12512 kbps     65132 kbps
Actual Aggregate Tx Power:        7.6 dBm      13.9 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
  Line Attenuation(dB): 5.6 31.9 48.1   N/A   N/A 15.2 40.8 62.3
Signal Attenuation(dB): 5.6 31.4 47.6   N/A   N/A 18.6 40.5 62.5
SNR Margin(dB): 5.9 5.9 5.9   N/A   N/A 2.9 2.9 3.0
TX Power(dBm): 0.6 -10.0 6.5   N/A   N/A 11.4 7.9 6.4
Sorry the formatting went weird but it looks like these statistics don't match, is there anything I can do to improve this?

To be fair though, other than the dropouts the line is out performing its maximum suggested 60 on bt wholesale.

[tubaman]

Can you run a xdslcmd info --stats and attach the results from that as it'll give more useful info?
 

[Black Sheep]

Hello,

On a VDSL line, is it normal for the connection to drop about every 7 days? It does seem to happen in the early morning.

During this time my router is logging an outage and failing over to 4G so it is down for a minute.

Using an HG612.ß

Thanks

I'll keep it simple with my own input.

A 3dB margin is probably the cause of the errors and the 'flappy' nature of your circuit.
To me, it's a play-off between speed v stability .... you've got ample speed so I would personally would ask for the DLM to have a hard-cap target-margin of 6dB. Problem over.

Or, you could spend the next 5yrs battling with the 3dB margin for the sake of circa 8Mbps loss in speed. Some would. 

[Alex Atkin UK]

Or, you could spend the next 5yrs battling with the 3dB margin for the sake of circa 8Mbps loss in speed. Some would. 

To be fair if its only dropping once a week, that's not terrible.  Now if it was dropping several times a day that would be a different matter.

[albert]

Can you run a xdslcmd info --stats and attach the results from that as it'll give more useful info?
 

Below, thanks for having a look

Code: [Select]

# xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 1
Last initialization procedure status: 0
Max: Upstream rate = 12598 Kbps, Downstream rate = 65132 Kbps
Bearer: 0, Upstream rate = 12679 Kbps, Downstream rate = 66348 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 3.1 6.4
Attn(dB): 20.4 0.0
Pwr(dBm): 13.9 7.5
VDSL2 framing
Bearer 0
MSGc: -6 26
B: 243 237
M: 1 1
T: 0 52
R: 10 16
S: 0.1171 0.5968
L: 17352 3405
D: 8 1
I: 254 127
N: 254 254
Q: 8 0
V: 0 0
RxQueue: 72 0
TxQueue: 18 0
G.INP Framing: 18 0
G.INP lookback: 18 0
RRC bits: 0 24
Bearer 1
MSGc: 154 -6
B: 0 0
M: 2 0
T: 2 0
R: 16 0
S: 6.4000 0.0000
L: 40 0
D: 3 0
I: 32 0
N: 32 0
Q: 0 0
V: 0 0
RxQueue: 0 0
TxQueue: 0 0
G.INP Framing: 0 0
G.INP lookback: 0 0
RRC bits: 0 0
Counters
Bearer 0
OHF: 0 1925036
OHFErr: 43 17
RS: 1350559784 3954729
RSCorr: 44867282 2034
RSUnCorr: 0 0
Bearer 1
OHF: 10330023 0
OHFErr: 0 0
RS: 103299611 0
RSCorr: 4870 0
RSUnCorr: 0 0

Retransmit Counters
rtx_tx: 207513621 0
rtx_c: 62590048 0
rtx_uc: 39768 0

G.INP Counters
LEFTRS: 124 0
minEFTR: 65234 0
errFreeBits: 2044012935 0

Bearer 0
HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 3630699083 0
Data Cells: 315773840 0
Drop Cells: 0
Bit Errors: 0 0

Bearer 1
HEC: 0 0
OCD: 0 0
LCD: 0 0
Total Cells: 0 0
Data Cells: 0 0
Drop Cells: 0
Bit Errors: 0 0

ES: 78 81
SES: 12 0
UAS: 66 56
AS: 165930

Bearer 0
INP: 49.00 0.00
INPRein: 1.00 0.00
delay: 0 0
PER: 0.00 7.78
OR: 0.01 32.86
AgR: 66415.96 12712.38

Bearer 1
INP: 4.50 0.00
INPRein: 4.50 0.00
delay: 3 0
PER: 16.06 0.01
OR: 79.68 0.01
AgR: 79.68 0.01

Bitswap: 104409/104409 5965/5977

Total time = 1 days 6 hours 14 min 30 sec
FEC: 380510672 17343
CRC: 796 81
ES: 78 81
SES: 12 0
UAS: 66 56
LOS: 1 0
LOF: 8 0
LOM: 0 0
Latest 15 minutes time = 14 min 30 sec
FEC: 204212 2
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 231621 9
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 6 hours 14 min 30 sec
FEC: 6605508 242
CRC: 4 0
ES: 2 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 1 day time = 24 hours 0 sec
FEC: 22729959 1107
CRC: 39 8
ES: 11 8
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Since Link time = 1 days 22 hours 5 min 29 sec
FEC: 44867282 2034
CRC: 43 17
ES: 13 17
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0

[Alex Atkin UK]

ES looks more normal here to me, so maybe its just a burst when the neighbours turn something specific on once a week?

[Black Sheep]

To be fair if its only dropping once a week, that's not terrible.  Now if it was dropping several times a day that would be a different matter.

Terrible enough for the OP to create a post about it, though  .

Get it to 6dB and be stress-free 

[atkinsong]

Get it to 6dB and be stress-free 

How do you suggest he does that with ORs fully automated DLM system? ISPs have no control over it.

[tubaman]

The only concern I see in is the SES in the Total Time stats, the time for which is oddly lower than the Since Link Time stats and which doesn't have those SES. Even that number is hardly high unless they were consecutive SES.
I'm wondering if there is a SHINE issue that is causing a high error burst and making it resync?

[Alex Atkin UK]

Terrible enough for the OP to create a post about it, though  .

Get it to 6dB and be stress-free 

Seems more they are curious why its doing it rather than bothered by it.  Personally I'd be more annoyed by losing 8Mbit to try to fix something if I barely notice it happening.  It really comes down to if you're actively using the connection at the time it happens, if not, I'd leave it alone.

[albert]

Thanks for your input everybody - I seem to be getting the idea that there isn't much I can do about it?

[tiffy]

How do you suggest he does that with ORs fully automated DLM system? ISPs have no control over it.

Thinking back to my FTTC VDSL-2 days, I believe that application of a modem speed clamp to the DS synch rate, lower value than current DLM applied DS synch rate will result in a higher DS SNRM value being applied on re-synch.
Again from memory, I think the old Huawei HG612 modem will accept such a speed clamp command, there are lots of historical posts on this forum outlining the method to achieve this.
Think the modem applied clamp will survive a DLM re-synch but not a power recycle, used to know, may be wrong!

Of course, you would need to decide how severe a DS clamp is applied against how much DS synch speed you are willing to sacrifice, should at least test BS's theory on better stability with higher DS SNRM provided there is no other issue on the line such as SHINE as "tubaman" as suggested may be a possibility.

Looking at your modem stat's, you are on G.Inp DS re-tx high profile which should revert to low profile via DLM action if sufficient DS synch clamp is applied (takes a few days) so that would slightly mitigate your DS data speed loss.

[albert]

It's dropped again since posting but again resynced relatively quickly so unsure what I can do really, can't imagine calling my ISP will be much help.

Confusingly, my down SNRM is now 2.6 which from my little understanding I think should be increasing because of this