EdgeOS Edge goes offline forever if cellular router loses signal

[AlexBeagle]

The Jetson Orin Nano is running Ubuntu 20.04.6, and it gets its signal from a cellular router (zr2000 by ziwi) with a teal sim card inside (but this bug happens on any provider). If you lose connection with a cellular tower, the edge will go offline and stay that way no matter how long you wait. The only way to fix this is to power cycle or unplug and replug the ethernet cable into the unit.

[AlexBeagle]

Connectivity test summary:

Losing connection makes EdgeOS stop working:

If you lose connection while the nano is running and online on EdgeOS (like if you go to a low signal area, or move the antenna up and down to good and bad signal areas) it will go offline on EdgeOS and stay that way. You can only fix this if you power cycle the unit or unplug and replug the ethernet cable to the nano.

if you just unplug and replug the ethernet cable this problem doesn't occur, in fact it can actually be used to solve the connection loss disappearance issue. if you unplug the ethernet and plug it back in, the nano will come back online.

The antenna location makes a big difference:

moving the antenna up and down 2 feet makes it lose signal, meaning having an antenna mounted on a higher point would help signal stability.

Hologram vs Teal:

Hologram:

Pros: has issues with consistent signal due to it always switching towers, at the moment we don't know how to get around this. the connection is very unstable and EdgeOS (which is already known to dislike unstable signals) struggles with tunneling, maintaining connection, etc. It takes 6 tries on average to SSH into a hologram device, and the connection will likely break while you're working on something.

Pros: It is pretty fast, 30 Mbps.

NOTE: It is unclear why Hologram works so much better at Linden than in the office or Fresno/Wasco.

Teal:

Pros: Very reliable signal. Easy to SSH into, very consistent, and reasonably smooth.

Cons: are that it is around 10 times slower, at 3 MBPS. Multiple SIM cards have “queued” status errors. The customer service is awful.

[wingchen]

I will reach out for a test env in this case.

[wingchen]

I see that the interface is eth0 . let's see if we are able to reset OS connection with the following commands:

• try nmcli device disconnect eth0 and then nmcli device connect eth0 to reconnect.
• try sudo ip link set eth0 down and then sudo ip link set eth0 up , if 1 does not work
• finally, if none of them work above, maybe try sudo systemctl restart NetworkManager

if any of them is proven working in the field, we can think about the right way to automate the resetting
please feel free to pause between disconnection and connection, and make sure the device shows offline on EdgeOS first