Random intermittent hub outages cured by access from a wired device
 

I am experiencing random intermittent hub freezes, which seem to be cured instantly when a wired device connected directly to the hub accesses the internet. This has been going on for years, and I've been swapping components one by one without finding the cause. I'm currently baffled, so asking for help from the hive mind.

It happens on average once a month. But sometimes we get two in two days, sometimes none for two months.

Current Configuration:

Volt M200 broadband, GU post code.
Hub 5 - installed only 30 days ago
Port 1 on hub connects to a four port Ethernet switch with a laptop, fileserver, and printer
Port 2 on hub connects to a DecoX55 mesh wifi hub, with wired backhaul to two other DecoX55s, each of which have a two port switch built in from which I connect to a wired device.
We use the Deco mesh wifi, so wifi on the Superhub is switched off to avoid any possibility of frequency conflicts.

Symptoms: when the error occurs, wireless devices can still connect to the Deco, but the Deco maintenance utility reports it has lost internet access. A laptop connected via the Ethernet switch also says it has no internet connectivity.

Cure: Turning the Hub5 off for 5 mins then on again will bring back service. But quicker than that, if I connect a laptop directly to one of the hub ports and open a web site, everything else springs back to life instantly. (The location of the hub prevents me from leaving any devices permanently directly connected to it.)

While directly connected, I have had a look in the hub logs and found entries like these around about the time of the failures:

Warning

RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value
Corresponding to the Top of the DRW;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS
MAC=xx:x:x:xx:xx:xx;CM-QOS=1.1;CM-VER=3.1;

Critical

Started Unicast Maintenance Ranging - No Response received - T3 timeout;CM-MAC= xx:x:x:xx:xx:xx;CMTS-MAC= xx:x:x:xx:xx:xx;CMQOS=1.1;CM-VER=3.1;

Error

DHCP RENEW WARNING - Field invalid in response v4 option;CMMAC= xx:x:x:xx:xx:xx;CMTS-MAC= xx:x:x:xx:xx:xx;CM-QOS=1.1;CMVER=3.1;

(MAC addresses masked out).

I'm curious to know if these could be relevant to the failures I am seeing.

This pattern of random intermittent outages has gone on for many years. Before the Deco mesh Wifi I used a second wifi hub with better coverage than the Virgin hubs - with similar behaviour. I've also tried changing out the Ethernet switches. At once stage I was using powerline connections to distant wired devices and thought they were the problem. But they are all gone now. My most recent theory was that my last hub, a Virgin Superhub3, must be faulty or old. But a brand new Hub5 is displaying the same behaviour.

All suggestions very much appreciated.

Re: Random intermittent hub outages cured by access from a wired device
 

The DHCP RENEW warning is normal and arises due to the way VM choose to renew the modem’s lease to the system. So forget that.

The other two messages are related, the latter being a consequence of the former.

There is a line impairment which is causing power increase requests so that the modem and CMTS can understand each other. This may be due to a particular channel misbehaving and when you reboot, that channel may no longer be present and it works again until the impairment affects another channel.

IMO, this is a physical issue; either a loose connector anywhere from the outside box on your house to the modem, or further up the system.

To try and pinpoint this further, please post your upstream and downstream stats when this happens and before you reset the modem. I would be looking for an anomalous reading.

For the moment, I’m ignoring the wired plug-in as this may have been done after the modem has soft reset itself.

Re: Random intermittent hub outages cured by access from a wired device
 

Hi,
I'm on a GU3 postcode and contstantly having disconnects but im on a Hub 3

Did you ever sort out the problem ?