Keeping PPP connection alive while Tunneling without SpaceBridge


#1

So I’ve just followed the instructions here:
https://hologram.io/docs/guide/cloud/spacebridge-tunnel/#tunneling-without-the-spacebridge-client

And managed to get a connection going.

I am connecting to a Pi 3B+ with the NovaM (NB-IoT turned off), from a Windows 10 machine.

The Pi is also connected on a wifi network, running headless. I am able to SSH into the Pi using PuTTy on the wifi (using the Pi’s local IP address on port 22), and then sign in and start the PPP connection using sudo hologram network connect.

Once the ppp0 connection is set up (as seen in ifconfig, I use Windows PowerShell, to start the tunnel connection according to the instructions, with ssh -p 999 -L 5000:link<mylink#>:22 -N -i spacebridge.key htunnel@tunnel.hologram.io
and sign in with my passphrase.

I then open another Powershell terminal, and use ssh -p 5000 pi@localhost to sign into the Pi. The Pi then logs into the CLI. (To be honest, figuring this step out took awhile as it isn’t really spelled out in the directions. I found this post which described it to someone else struggling to make sense of what to do next: https://community.hologram.io/t/huawei-e353-ssh/877/6

Anyway, the resulting connection is extremely slow/laggy. If I type a command, it takes many seconds or longer for the letters to even show up on the CLI. I may type out a command, lets say sudo ifconfig ppp0, and the letters I’m typing don’t even show up for 10 or 20 seconds.

However, if I type something into my tunneled PowerShell Pi session, and then immediately hop over to my original (local wifi) PuTTy ssh session, and ping (ping -I ppp0 -c 1 8.8.8.8) out on PPP from the pi, then the tunneled connection immediately speeds up for the next several seconds.

My hunch is this is related to these topics about keeping the connection alive:
https://community.hologram.io/t/huawei-e353-ssh/877
and
https://community.hologram.io/t/keeping-pppd-connection-alive/646
and probably others.

Both of those topics ended with users asking for answers to this issue, and both went largely unanswered.

What am I doing wrong here, and do you have any suggestions for dealing with the delay/lag? I’d rather not have the Pi constantly pinging away wasting data in order to use the PPP connection in this way.

I see @HologramPat discuss what might be a similar problem here:
https://community.hologram.io/t/dash-modem-times-out-and-wont-send-data-after-1-hour/240/24

…but I don’t know if this is the same issue, as the lag presents itself from the beginning, and persists indefinitely unless I ping out from the Pi. Additionally, it returns to a lagging state almost immediately after I stop pinging (no more than a few seconds).

The PPP connection set up in this way (tunneling without SpaceBridge through ssh with port forwarding), is nearly unusable in this state. What am I doing wrong here?

Thank you,
Blake


Huawei E353 & SSH
#2

Still interested in getting some insight on this issue (inbound ppp connections only working during or directly after device pings outbound)…

Anyone else experiencing this? I’ve also noticed this same issue while using SpaceBridge too.