Continual disconnections - does this look right in any way?

[daveboulden]

I've been a customer since the Telewest/Blueyonder days and this is the first time I've had such a bad run of connectivity. I think my Hub 4 may be failing. I have checked all connections to my kit internally. I have the Hub 4 in  router mode feeding an Asus RT-AX89X which in turn connects to a the rest of my internal network via an 10Gbit SFP+ connection to a Mikrotik CRS328-24P-4S+. When a disconnection occurs, I have tested running a speed test on my Asus router (being the nearest item connected to the hub) and it times out and won't work until the hub reconnects, leading me to believe the Hub 4 is the culprit of the issues as the postcode-based checker claims there are no issues in my area (ME10 4UT).

I have seen the convention is to set up a BQM, so here's the last 24hrs on the one I set up yesterday:

Does this in any way look normal or point to the Hub 4 being the likely culprit?

[daveboulden]

and upstream:

3.0 Upstream channels
Channel	Frequency (Hz)	Power (dBmV)	Symbol Rate (ksps)	Modulation	Channel ID
1	23600000	43.5	5120 KSym/sec	QAM64	11
2	36600000	44.5	5120 KSym/sec	QAM64	7
3	30100000	44	5120 KSym/sec	QAM64	8
4	43100000	44.8	5120 KSym/sec	QAM64	6
5	49600000	44.8	5120 KSym/sec	QAM64	5

3.0 Upstream channels
Channel	Channel Type	T1 Timeouts	T2 Timeouts	T3 Timeouts	T4 Timeouts
1	ATDMA	0	0	0	0
2	ATDMA	0	0	0	0
3	ATDMA	0	0	0	0
4	ATDMA	0	0	0	0
5	ATDMA	0	0	0	0

3.1 Upstream channels
Channel	Channel Width (MHz)	Power (dBmV)	FFT Type	Modulation
12	10.4	49.1	2K	QAM128

3.1 Upstream channels
Channel	Channel Type	Number of Active Subcarriers	First Active Subcarrier (Hz)	T3 Timeouts	T4 Timeouts
12	OFDMA	208	53.4	1	0

[Sephiroth]

Not that it’ll make much difference, the DS 3.1 channels are missing. From what is seen so far, those stats look fine. Was the Internet behaving well at that time?

[daveboulden]

It's difficult to tell as the connection is up and down every few minutes, so it would have disconnected more than once whilst I was copying and pasting the tables into my reply.

Just for completeness, these are the DS 3.1 channel stats:

3.1 Downstream channels
Channel	Channel Width (MHz)	FFT Type	Number of Active Subcarriers	Modulation (Active Profile)	First Active Subcarrier (Hz)
41	192	4K	3736	QAM4096	759
3.1 Downstream channels
Channel ID	Lock Status	RxMER Data (dB)	PLC Power (dBmV)	Correcteds (Active Profile)	Uncorrectables (Active Profile)
41	Locked	42	4.6	3270713740	4576

[Itzanotheruser]

I can see that you are trying to help daveboulden , Sephiroth  but the issue is hard to catch. As I said in my post, I have had at least four engineers out (some a couple of times) and they all found no issue as everything was in spec, but this was after that particular issue had resolved itself and all was calm.
Even when the issue is happening, the net itself is random with its on/off state, so trying to catch it in the off state is nigh on impossible. If you have the ability, use samknows to check their router for disconnects as mine was showing.

[Carley_S]

Hi @daveboulden 

Welcome back to the community forums.

Sorry to hear about your connection concerns. We can see on the system on our side that you've already been in touch with the team and have a visit arranged to investigate this further.

Please do keep us posted with how it goes and we'll offer any further support should you need it. 

[Itzanotheruser]

Might have a bit of an idea @daveboulden , whilst on the phone (mobile because the landline is useless in one of these .... issues times, cant keep a line open to get through the security checks) and in relation to my various issues, they had me do a pinhole reset at 4pm .. and I am not sure if it just happened to fix itself when this happened, or it did actually help but heres my BQ monitor for earlier...

This is not a fix by any stretch, but if it gets you back on a solid connection for a short while, it might stop you going mad.

[daveboulden]

Thanks for the suggestion. As it happens, I did actually already do that yesterday and it did briefly give me a slightly more usable connection for about 30 mins or so, but then it was straight back to the heavy packet loss. 

I have and engineer coming for a visit on Thursday, so hopefully something can be resolved then. I'll post here with any outcome.

[Itzanotheruser]

Fingers, toes and anything not tied down on my table is getting crossed for you.
If whatever they do works in the short term, leave it for best part of a month before you can call it fixed as mine can be good for a week or two, then <expletive> for a time .. hours or days.
I genuinly thought I had got rid of this issue, until yesterday. Hey ho .....

[daveboulden]

The engineer came promptly this morning and straight away swapped out my Hub 4 for a Hub 5. It has initially been much better for about 5 hours, but just in the last hour, the packet loss is back again:

You can clearly see when the hub was swapped out at around 8:30 am. However, at 2:30pm-ish, they seem to be back. 

Upon checking the network log on the hub, it seems to coincide almost exactly with a "US Profile assignment change" (the rows in bold):

Network Log

Time Priority Description

24-10-2024 14:55:03	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 14:42:01	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 14:37:18	notice	US profile assignment change. US Chan ID: 12; Previous Profile: 12 13; New Profile: 11 13.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
24-10-2024 14:32:15	notice	US profile assignment change. US Chan ID: 12; Previous Profile: 11 13; New Profile: 12 13.;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
24-10-2024 09:58:19	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 09:09:06	error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
24-10-2024 09:00:39	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 09:00:28	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 08:59:37	notice	GUI Login Status - Login Success from LAN interface
24-10-2024 08:45:52	notice	REGISTRATION COMPLETE - Waiting for Operational status

What is a "US Profile assignment change"? It seems to be very linked to the issue I have been experiencing.

[Sephiroth]

This is rather complex.  To keep it simple, the VM end (CMTS) sees issues with upstream data integrity and sets boundaries with which the hub can work.  IUC 13 is 16QAM and most failure tolerant, IUC 12 is faster (I don't know the modulation width) and IUC 13 even faster.  The 5 minute gap between messages is standard as the CMTS takes another look at your hub's upstream data integrity.

To muddy the waters further, "IUC" stands for Interval Usage Code and that's even more complex, on which I won't elaborate.

In short, it seems that your problem lies with the upstream and your neighbours will likely have the same.