on 22-06-2020 16:04
Hi All,
first post here, and its for syc timing errors. this issues started a few days ago , the internet was cutting out and then coming back. i have rebooted all the kit. switched it off for 10 mins and then turned it back on etc etc. still getting the same issue. called VM and the automated system said they needed to send a signal to the kit, did that and it rebooted everything. still same issue.
Network Log:
Time | Priority | Description |
22/06/2020 10:35:56 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
22/06/2020 10:35:56 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
22/06/2020 09:00:45 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
22/06/2020 06:41:17 | Error | DHCP REBIND WARNING - Field invalid in response;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 23:10:52 | Error | DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 18:03:14 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 17:58:32 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 17:28:4 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 15:40:31 | Error | DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 09:14:47 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 09:13:50 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 08:22:22 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
21/06/2020 00:39:48 | Error | DHCP RENEW sent - No response for IPv4;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
20/06/2020 21:58:27 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
20/06/2020 21:58:27 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
20/06/2020 21:57:0 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
20/06/2020 21:18:8 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
20/06/2020 21:16:36 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
Answered! Go to Answer
on 23-06-2020 00:46
on 23-06-2020 07:01
Synchronisation failure is where the hub can't maintain a lock on one or more of the 28 channels it uses to connect with the gear in the street cabinet. And when it does lose synch, that loss of one or more channels becomes a "partial service". What that means for the customer is slowdowns, disconnection and poor latency. The hub does try and renegotiate the lost channel, but that takes time, and the problem will recur.
The underlying cause is usually noise on the upstream, because it is those channels that the hub uses to communicate with the gear in the street cabinet. The upstream looks OK on the data you've posted, but that's most likely because you've recently rebooted the hub (I can tell that from the low error counts). Rebooting causes the hub to renegotiate all 28 channels, and usually provides a temporary fix, but because the underlying cause isn't fixed, it will recur. Replacing the hub won't make a blind bit of difference - that's a cheap fix by agents who know nothing about the technology. If they'd looked at your network log and knew what it meant they'd have sent out a technician to find the real problem.
You can try dialling it in, but chances are you'll get more of a run around by the utter clowns that VM use as offshore technical support. Better to wait (maybe a day or two) for the UK based VM forum staff to get round to this post and advise on next steps. They're usually very helpful, but don't accept the excuse "I've had a look and everything appears OK from our side" - the Network log is crystal clear on the fault and the impact on your service, and that's been recorded by VM's own equipment. You need a technician.
on 29-06-2020 10:32
There's no harm in plugging in the replacement hub (other than the inconvenience of setting it up, getting it activated, and reconnecting all your wireless devices). And at least you've then gone along with VM's initial (if misguided) effort to resolve the problem. Who knows, MAYBE it will work, I just don't expect it to.
If/when it doesn't work then VM have to accept that any subsequent problems aren't down to the hub, and will have to send a technician.
on 22-06-2020 16:05
Levels:
Downstream bonded channels
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 | 291000000 | -3.7 | 40 | 256 qam | 20 |
2 | 267000000 | -3.5 | 38 | 256 qam | 17 |
3 | 275000000 | -3.2 | 40 | 256 qam | 18 |
4 | 283000000 | -3.7 | 40 | 256 qam | 19 |
5 | 299000000 | -2.9 | 38 | 256 qam | 21 |
6 | 307000000 | -2.7 | 40 | 256 qam | 22 |
7 | 315000000 | -2.5 | 40 | 256 qam | 23 |
8 | 323000000 | -2.7 | 38 | 256 qam | 24 |
9 | 331000000 | -2.7 | 40 | 256 qam | 25 |
10 | 339000000 | -2.7 | 38 | 256 qam | 26 |
11 | 347000000 | -2.7 | 40 | 256 qam | 27 |
12 | 355000000 | -3 | 40 | 256 qam | 28 |
13 | 363000000 | -2.9 | 40 | 256 qam | 29 |
14 | 371000000 | -2.9 | 40 | 256 qam | 30 |
15 | 379000000 | -2.9 | 40 | 256 qam | 31 |
16 | 387000000 | -3 | 40 | 256 qam | 32 |
17 | 395000000 | -3.2 | 38 | 256 qam | 33 |
18 | 403000000 | -3.9 | 38 | 256 qam | 34 |
19 | 411000000 | -4.2 | 38 | 256 qam | 35 |
20 | 419000000 | -4.4 | 40 | 256 qam | 36 |
21 | 427000000 | -4.2 | 40 | 256 qam | 37 |
22 | 435000000 | -4.2 | 38 | 256 qam | 38 |
23 | 443000000 | -4.4 | 40 | 256 qam | 39 |
24 | 451000000 | -4 | 40 | 256 qam | 40 |
Downstream bonded channels
Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 | Locked | 40.3 | 4 | 0 |
2 | Locked | 38.9 | 4 | 0 |
3 | Locked | 40.3 | 5 | 0 |
4 | Locked | 40.3 | 12 | 0 |
5 | Locked | 38.9 | 6 | 0 |
6 | Locked | 40.9 | 5 | 0 |
7 | Locked | 40.3 | 6 | 0 |
8 | Locked | 38.9 | 5 | 0 |
9 | Locked | 40.3 | 1 | 0 |
10 | Locked | 38.9 | 5 | 0 |
11 | Locked | 40.3 | 5 | 0 |
12 | Locked | 40.3 | 6 | 0 |
13 | Locked | 40.3 | 6 | 0 |
14 | Locked | 40.3 | 5 | 0 |
15 | Locked | 40.3 | 3 | 0 |
16 | Locked | 40.3 | 5 | 0 |
17 | Locked | 38.9 | 4 | 0 |
18 | Locked | 38.9 | 0 | 0 |
19 | Locked | 38.6 | 6 | 0 |
20 | Locked | 40.3 | 5 | 0 |
21 | Locked | 40.3 | 6 | 0 |
22 | Locked | 38.9 | 6 | 0 |
23 | Locked | 40.3 | 4 | 0 |
24 | Locked | 40.9 | 5 | 0 |
Upstream bonded channels
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
1 | 53700000 | 4.65 | 5120 | 64 qam | 2 |
2 | 39400000 | 4.575 | 5120 | 64 qam | 4 |
3 | 46200000 | 4.625 | 5120 | 64 qam | 3 |
4 | 32600000 | 4.55 | 5120 | 64 qam | 5 |
Upstream bonded 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 |
Another thing i have noticed, i seem to flat out at 160Mb/s download and never get the advertised 350Mb/s and thats connected to the device wired:
on 22-06-2020 16:16
I should also add, im on the 350Mb/s service, up until now i have never really experienced any issues with my service. I am a heavy user, as i work from home well before any of this covid 19 stuff kicked off, so i need a reliable connection.
i called VM helpdesk and the guy on the phone said it was a problem with the wireless portion of the hub so is sending out a new hub that will be with me on wednesday?? even though i explained to him it wasnt a wifi issue, and that i was hard wired.
on 22-06-2020 22:51
Network Log
Time Priority Description
22/06/2020 20:47:5 | Warning! | RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
22/06/2020 20:47:5 | critical | SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0; |
on 23-06-2020 00:46
on 23-06-2020 07:01
Synchronisation failure is where the hub can't maintain a lock on one or more of the 28 channels it uses to connect with the gear in the street cabinet. And when it does lose synch, that loss of one or more channels becomes a "partial service". What that means for the customer is slowdowns, disconnection and poor latency. The hub does try and renegotiate the lost channel, but that takes time, and the problem will recur.
The underlying cause is usually noise on the upstream, because it is those channels that the hub uses to communicate with the gear in the street cabinet. The upstream looks OK on the data you've posted, but that's most likely because you've recently rebooted the hub (I can tell that from the low error counts). Rebooting causes the hub to renegotiate all 28 channels, and usually provides a temporary fix, but because the underlying cause isn't fixed, it will recur. Replacing the hub won't make a blind bit of difference - that's a cheap fix by agents who know nothing about the technology. If they'd looked at your network log and knew what it meant they'd have sent out a technician to find the real problem.
You can try dialling it in, but chances are you'll get more of a run around by the utter clowns that VM use as offshore technical support. Better to wait (maybe a day or two) for the UK based VM forum staff to get round to this post and advise on next steps. They're usually very helpful, but don't accept the excuse "I've had a look and everything appears OK from our side" - the Network log is crystal clear on the fault and the impact on your service, and that's been recorded by VM's own equipment. You need a technician.
on 23-06-2020 16:12
Hi Bill_Carson, thanks for the message and we are sorry to hear that you have been having issues with the service? If so, we will fire over a private message to you. Chris
on 29-06-2020 10:17
Thanks, i checked and the cable is tight. apologies for the delayed response been busy with work so totally haven't had the time to jump on here.
on 29-06-2020 10:20
Thanks for your response i received the new router, i guess there is no point plugging it in.
on 29-06-2020 10:21
Hi, I am still having issues.