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Hologram Spacebridge lets you create authenticated SSH tunnels to devices on the Hologram cellular network.

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Enable secure device tunneling

You can enable tunneling for a single SIM or for multiple SIMs from the Dashboard.
Note: You must configure your device’s network interface to support inbound connections.

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Generate an SSH key and upload to the API

You only need to complete this section the first time you’re setting up the tunnel on this computer. If you already have an SSH key-pair that you’d like to use, skip to step 2.
1

Generate an SSH key-pair

Use ssh-keygen to generate a SSH key-pair:
ssh-keygen -f spacebridge.key -b 4096 -t rsa
2

Upload the public key to the API

Upload your public key to the Hologram API. In the code below, replace ~APIKEY~ with your Hologram API key. Your personal API can be found in your dashboard by clicking on the Account section in the main menu and selecting API tab at the top of the screen. If you are using a key that you already generated, replace the filename in the export command.The filename ends in .pub, not .key. If you use the .key file this will upload your private key which you don’t want to do.
PUBKEY=$(cat spacebridge.key.pub)
curl -X POST \
  -H "Content-Type: application/json" \
  -u apikey:YOUR_HOLOGRAM_API_KEY \
  -d '{"public_key":"'"$PUBKEY"'"}' \
  "https://dashboard.hologram.io/api/1/tunnelkeys?apikey=~APIKEY~"
The same command can also be run with Powershell in Windows:
$pub = (Get-Content .\spacebridge.key.pub -Raw).Trim(); Invoke-RestMethod -Uri "https://dashboard.hologram.io/api/1/tunnelkeys?apikey=YOUR_HOLOGRAM_API_KEY" -Method Post -ContentType "application/json" -Body (@{public_key = $pub} | ConvertTo-Json)
You should get a successful response back. Users can have up to 5 active device tunneling keys (to enable or disable keys follow these instructions).

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Open the tunnel with SSH port forwarding

1

Find your SIM's link (profile) ID

Look up the link (profile) ID for the SIM you are trying to tunnel into. In your dashboard you can find this number by navigating to the SIM’s details page and opening the Profiles tab.
2

Open the tunnel with SSH port forwarding

The command below will open up the tunnel. You can see in this command where you would replace the link ID (999999) with your own ID. In this case, port 22 is the port on the device, and port 5000 is the local port being forwarded. Replace spacebridge.key with whatever private key you are using. This should be key file that goes with the .pub file that you uploaded to the Hologram API.
ssh -p 999 -L 5000:link999999:22 -N -i spacebridge.key htunnel@tunnel.hologram.io -v
3

Connect over SSH

You should now be able to connect to port 22 on your device from port 5000 on the local host (example here).

Enable/disable tunneling keys via API

View tunneling keys via API