Stuck on DLM Profile

[DiscoDave1]

Hi,

After a power cut I got put on a 35Mbit down / 10Mbit up DLM band. Been 4 weeks or so without any issues but I can't seem to budge out of DLM. Phone line test for noise is fine, spoken to BT online who say there's nothing wrong with the line, but DLM still won't come off my connection.

Any ideas what to try next?

Thanks,

[licquorice]

Patience, unfortunately. It can take months for DLM to release banding. There may not be any audible noise but there may still be an impairment to your line causing errors.

[DiscoDave1]

BT state there's nothing wrong with my line but still on a DLM band 2 months after, sadly.

[PaddyB]

Hi @DiscoDave1,

Thank you for posting. I'm sorry if your connection has been banded. You should have seen the banding lift as long as the connection has been stable. Are you seeing any disconnections?

To get a better understanding of what is happening with your connection, please could you post your router stats?

If you are using the BT Smart hub you can get your connection stats by, Opening a new web browser on your connected device and type 192.168.1.254 or bthomehub.home into the address bar. This will open the Hub Manager.  Click ‘Advanced Settings’ and then ‘Technical log’.

Thanks,

Paddy

[DiscoDave1]

Hi@PaddyB 

Not noticing many disconnects. Stats:

xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason:	1
Last initialization procedure status:	0
Max:	Upstream rate = 8936 Kbps, Downstream rate = 38868 Kbps
Bearer:	0, Upstream rate = 8936 Kbps, Downstream rate = 35000 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):	 7.4		 6.2
Attn(dB):	 22.4		 0.0
Pwr(dBm):	 13.1		 5.8
			VDSL2 framing
			Bearer 0
MSGc:		-6		26
B:		73		237
M:		1		1
T:		0		38
R:		6		16
S:		0.0666		0.8460
L:		9610		2402
D:		8		1
I:		80		127
N:		80		254
Q:		8		0
V:		5		0
RxQueue:		132		0
TxQueue:		33		0
G.INP Framing:		18		0
G.INP lookback:		31		0
RRC bits:		0		24
			Bearer 1
MSGc:		90		-6
B:		0		0
M:		2		0
T:		2		0
R:		16		0
S:		10.6667		0.0000
L:		24		0
D:		1		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		447691
OHFErr:		291		2431
RS:		3274166136		1841298
RSCorr:		8685452		80382
RSUnCorr:	0		0
			Bearer 1
OHF:		34691984		0
OHFErr:		0		0
RS:		208151533		0
RSCorr:		98		0
RSUnCorr:	0		0

			Retransmit Counters
rtx_tx:		692961631		0
rtx_c:		349338		0
rtx_uc:		243624		0

			G.INP Counters
LEFTRS:		564		0
minEFTR:	34989		0
errFreeBits:	1815722897		0

			Bearer 0
HEC:		0		0
OCD:		0		0
LCD:		0		0
Total Cells:	3145176163		0
Data Cells:	492320868		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:		468		2309
SES:		46		351
UAS:		70		51
AS:		557247

			Bearer 0
INP:		52.00		0.00
INPRein:	1.00		0.00
delay:		0		0
PER:		0.00		8.06
OR:		0.01		31.73
AgR:		35418.64	8967.74

			Bearer 1
INP:		2.50		0.00
INPRein:	2.50		0.00
delay:		0		0
PER:		16.06		0.01
OR:		47.81		0.01
AgR:		47.81	0.01

Bitswap:	275886/275886		5340/5357

Total time = 1 days 21 hours 49 min 20 sec
FEC:		34919683		689592
CRC:		3680		16434
ES:		468		2309
SES:		46		351
UAS:		70		51
LOS:		1		0
LOF:		10		0
LOM:		4		0
Latest 15 minutes time = 4 min 20 sec
FEC:		3395		0
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:		11512		2
CRC:		0		1
ES:		0		1
SES:		0		0
UAS:		0		0
LOS:		0		0
LOF:		0		0
LOM:		0		0
Latest 1 day time = 21 hours 49 min 20 sec
FEC:		1161543		5319
CRC:		29		178
ES:		7		31
SES:		0		3
UAS:		0		0
LOS:		0		0
LOF:		0		0
LOM:		0		0
Previous 1 day time = 24 hours 0 sec
FEC:		2659344		14161
CRC:		36		400
ES:		11		51
SES:		0		6
UAS:		0		0
LOS:		0		0
LOF:		0		0
LOM:		0		0
Since Link time = 6 days 10 hours 47 min 25 sec
FEC:		8685452		80382
CRC:		291		2431
ES:		58		389
SES:		4		45
UAS:		0		0
LOS:		0		0
LOF:		0		0
LOM:		0		0
# 

Stats recorded 22 Feb 2022 11:26:14

DSLAM type / SW version:	BDCM:0xa4a1 (164.161) / v0xa4a1
Modem/router firmware:  	AnnexA version - A2pv6C038m.d24j
DSL mode:               	VDSL2 Profile 17a
Status:                 	Showtime
Uptime:                 	6 days 10 hours 49 min 27 sec
Resyncs:                	0 (since 22 Feb 2022 11:21:12)
			
				Downstream	Upstream
Line attenuation (dB):  	22.4		0.0
Signal attenuation (dB):	Not monitored		
Connection speed (kbps):	35000		8936
SNR margin (dB):        	7.4		6.2
Power (dBm):            	13.1		5.8
Interleave depth:       	8		1
INP:                    	52.00		0
G.INP:                  	Enabled		Not enabled
Vectoring status:       	5 (VECT_UNCONFIGURED)		

RSCorr/RS (%):          	0.2648		3.3375
RSUnCorr/RS (%):        	0.0000		0.0000
ES/hour:                	0		0

[imjolly]

the connection time is only 6 days suggesting possible drops in connection or was it manual reset  if you have banded profile removing it will only increase speed by 1/2 mb as attainable is only 38mb

[DiscoDave1]

I think for that example it may have been a manual reset.

When I've not been banded I've sync'd at circa 43Mbit

[imjolly]

at present your stats show attainable at 38mb and this is not affected whether banded or not

any manual reset restarts your waiting time for DLM to lift banding

[licquorice]

I could be wrong, but I think attainable rate is predicated on an SNRm of 6dB, so if 3dB margin is available actual rate would be higher than the predicted attainable if you see what I mean.

That is certainly the case with my line.

I am currently banded at 49 (again!!) with a max of 55, but when DLM is reset and 3dB margin kicks in, my actual is about 63.

[DiscoDave1]

Weirdly, I had it in the past where my synchronised rate is a higher than my attainable, according to my Openreach modem.

27 days of solid uptime and still on DLM