Question

This is a seemingly strange problem.

We have a growing number of RUT240 units running on 3G/4G multisims which are permanently set to VPN connect to fixed IP ADSL line Draytek 2862 modems at different locations which we use as backbone connections.

Twice now, at around the same time (the latest incident was at 00:30 hours GMT 9th July 2019) all of the units drop their VPN connections and then reconnect a couple of minutes later. I've got a VPN email notification setup on the Draytek units to email me if the VPN connection fails which is why I know it happens.

I know it's not the SIM cards or Draytek units as we have one location with the same 3G/4G multisim in a Draytek 3G/4G modem and that VPN backbone connection does not drop which points to the RUT240's.

Anyone have any suggestion as to why this might happen at the same time? The firmware update option is off.

Kind Regards

Tony

Answer 1

Hello,

Multiple devices cannot stop functioning at exactly the same time, unless they are configured to do so, or if there is an external trigger/reason for that.

If your RUT240 routers are not configured to auto reboot at exactly the same time (from "Services -> Auto reboot" menu), then this issue is not related with the routers (since multiple devices experienced it at the same time).

Plausible reason what might have happened:

 - There was an issue from mobile operator side which caused massive disconnection from mobile operator network. Indication what some of the devices remained connected does not mean anything, since it is possible that not all of mobile network experienced an issue (e.g. maybe some mobile operator frequencies stopped forwarding briefly, while others was working fine. This would mean that device, which were using different 3G/LTE frequency than your RUT240 would still be connected to the network, when RUT240 would be disconnected from the network).

 - There was a brief power outage in specific area.

Comments

Yes, you're quite right, I wrongly made the assumption that because only the RUT240 units were dropping and not the Draytek ones, that the problem was on the RUT240 - assuming to be something like a background update or time related glitch. I've delved into the logs on the units and it appears that the EE network disconnected the connection at that time globally which is why they all dropped. Thank you for your detailed reply.