Modem Mode on Hub 4 won't work - no DHCP/WAN connection (but connection fine in Router Mode)

[mercilesskiller]

Hi All

I've had an issue with my Hub 4 come up overnight which I'm wondering if anyone has any ideas around. 

I have a 500mb Virgin connection which works fine when the Hub 4 is in router mode. It has been operating however in Modem Mode, connected to a Netgear Raxe300 NightHawk with no problem for months.

I woke up this morning with no connection. Hub 4 light was still green. When looking on the Netgear router, there was no IP address coming on the WAN port of the Netgear (DHCP didn't seem to be working). Reset Hub 4, nothing. Tried different cables, nothing, reset Netgear, nothing. Couldn't access the Hub 4 in modem mode through the Netgear because that internal IP (192.168.100.X) wasn't coming through DHCP. 

I manually set a static IP on the WAN port of the Netgear to 192.168.100.13/255.255.255.0 with default gateway as .1 - through this I COULD then connect to the UI for the Hub 4 (success!). However, not the internet... I took some screenshots of the admin page on the Hub 4 but nothing seemed to suggest an issue. Note in the last screenshot there's no IP/WAN information though when in router mode, on this page it does show a WAN connection status.

For now I've flipped it back into Router Mode so accessing the internet via the Hub 4 but I really need to get the router working again in Modem Mode. Any ideas? It almost feels like there's been some firmware update that's broken modem mode? It sounds like for whatever reason when in modem mode, it just won't connect externally nor will it give an internal IP to the Netgear - did plenty of "leaving it off for 2 minutes" and reconnecting but no luck.

Thanks!

[Roger_Gooner]

Can you post some stats.
Go to 192.168.0.1 (router mode) or 192.168.100.1 (modem mode), do not log in, click on the link "Check Router Status".

Copy and paste the Downstream, Upstream and Network Logs as text (not images). Mask any public IP address.

[mercilesskiller]

3.0 Downstream channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

25	331000000	8.000000	38.983261	QAM256	25
1	139000000	7.800003	38.983261	QAM256	1
2	147000000	8.000000	38.605377	QAM256	2
3	155000000	7.900002	38.983261	QAM256	3
4	163000000	7.699997	38.605377	QAM256	4
5	171000000	7.500000	38.605377	QAM256	5
6	179000000	7.099998	38.983261	QAM256	6
7	187000000	7.000000	38.983261	QAM256	7
8	195000000	6.800003	38.983261	QAM256	8
9	203000000	6.900002	38.983261	QAM256	9
10	211000000	6.699997	38.605377	QAM256	10
11	219000000	6.699997	38.983261	QAM256	11
12	227000000	6.599998	38.983261	QAM256	12
13	235000000	6.500000	38.983261	QAM256	13
14	243000000	6.300003	38.983261	QAM256	14
15	251000000	5.900002	38.983261	QAM256	15
16	259000000	5.599998	38.983261	QAM256	16
17	267000000	6.900002	38.605377	QAM256	17
18	275000000	7.699997	38.983261	QAM256	18
19	283000000	7.199997	38.983261	QAM256	19
20	291000000	7.099998	40.366287	QAM256	20
21	299000000	6.699997	38.983261	QAM256	21
22	307000000	7.099998	38.983261	QAM256	22
23	315000000	7.599998	40.366287	QAM256	23
24	323000000	7.900002	38.983261	QAM256	24
26	339000000	7.699997	38.983261	QAM256	26
27	347000000	7.599998	38.983261	QAM256	27
28	355000000	7.599998	40.366287	QAM256	28
29	363000000	8.000000	40.366287	QAM256	29
30	371000000	8.199997	40.366287	QAM256	30
31	379000000	8.300003	40.366287	QAM256	31

3.0 Downstream channels

Channel Lock Status RxMER (dB) Pre RS Errors Post RS Errors

25	Locked	38.983261	0	0
1	Locked	38.983261	0	0
2	Locked	38.605377	0	0
3	Locked	38.983261	0	0
4	Locked	38.605377	0	0
5	Locked	38.605377	0	0
6	Locked	38.983261	0	0
7	Locked	38.983261	0	0
8	Locked	38.983261	0	0
9	Locked	38.983261	0	0
10	Locked	38.605377	0	0
11	Locked	38.983261	0	0
12	Locked	38.983261	0	0
13	Locked	38.983261	0	0
14	Locked	38.983261	0	0
15	Locked	38.983261	0	0
16	Locked	38.983261	0	0
17	Locked	38.605377	0	0
18	Locked	38.983261	0	0
19	Locked	38.983261	0	0
20	Locked	40.366287	0	0
21	Locked	38.983261	0	0
22	Locked	38.983261	0	0
23	Locked	40.366287	0	0
24	Locked	38.983261	0	0
26	Locked	38.983261	0	0
27	Locked	38.983261	0	0
28	Locked	40.366287	0	0
29	Locked	40.366287	0	0
30	Locked	40.366287	0	0
31	Locked	40.366287	0	0

3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)

33

96

4K

1840

QAM4096

424

3.1 Downstream channels

Channel ID Lock Status RxMER Data (dB) PLC Power (dBmV) Correcteds (Active Profile) Uncorrectables (Active Profile)

33

Locked

42

8.6

160677876

0

[mercilesskiller]

3.0 Upstream channels

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID

1	36600000	43.020599	5120 KSym/sec	64QAM	7
2	23600000	43.270599	5120 KSym/sec	64QAM	11
3	30100000	43.270599	5120 KSym/sec	64QAM	8
4	43100000	42.770599	5120 KSym/sec	64QAM	6
5	49600000	42.770599	5120 KSym/sec	64QAM	5

3.0 Upstream channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1	US_TYPE_ATDMA	0	0	0	0
2	US_TYPE_ATDMA	0	0	0	0
3	US_TYPE_ATDMA	0	0	0	0
4	US_TYPE_ATDMA	0	0	0	0
5	US_TYPE_ATDMA	0	0	0	0

3.1 Upstream channels

Channel Channel Width (MHz) Power (dBmV) FFT Type Modulation

12

10.8

46.5

2K

QAM128

3.1 Upstream channels

Channel Channel Type Number of Active Subcarriers First Active Subcarrier (Hz) T3 Timeouts T4 Timeouts

12

OFDMA

220

53.4

0

0

[mercilesskiller]

Network Log

Time Priority Description

Wed Dec	5	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	No Ranging Response received - T3 time-out;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Wed Dec	5	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	No Ranging Response received - T3 time-out;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Tue Dec	5	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Tue Dec	3	No Ranging Response received - T3 time-out;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Tue Dec	5	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	No Ranging Response received - T3 time-out;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	Unicast Ranging Received Abort Response - initializing MAC;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Tue Dec	5	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;
Thu Jan	3	No Ranging Response received - T3 time-out;CM-MAC=[HIDDEN];CMTS-MAC=[HIDDEN];CM-QOS=1.1;CM-VER=3.1;

[mercilesskiller]

Weirdly on the last one, all the "Thu" entries are from 1970. The other days are all from this week (week of 4th December). The problem occurred both overnight on the 4th to the 5th and 5th to the 6th.

[Roger_Gooner]

Your log shows repeated failures of your modem and CMTS to communicate. Unless there is an area fault you need a tech to come round.

[mercilesskiller]

Weird - no faults show on status pages around my area... Should I expect this to just keep failing every single night? I suppose I'll see what happens tonight and see if it happens again first. 3 times in a row and then it does feel like too much of a coincidence..

[legacy1]

Copy your router Netgear WAN MAC to a PC NIC when router fails connect PC to hub in place of router without rebooting the hub.

Possibly a DHCP problem with VM but in order to see that with your router you need a switch with port mirroring to see it happening to a PC NIC using a USB to Ethernet adapter with Wireshark.

[mercilesskiller]

Not really sure how I do this because:

1) The problem happens overnight when asleep. 

2) When the problem happens, it's fixed by restarting the modem it seems

So unless the suggestion is to setup my PC NIC with the routers WAN MAC, connect it to the hub, get it running OK.. leave my PC on with wireshark trace going on overnight, and then see what's happened in the morning?

Although as the other poster said if the issue is the modem talking to CMTS then it may be best to just get an engineer around as ultimately they may be able to just test everything live.

[legacy1]

Yes you could do that with this filter

port 68 or port 67 or arp

It could be that VM are doing work and clear the DHCP table same goes for modems 10. which maybe why you need to reboot the hub which would mean your connection has its lease as good and not need to redo DHCP but unpluging replug the Ethernet should trigger the DHCP client to start over so try that with PC if you get not internet.