Android trust ADB host (RSA fingerprint) without USB connection

Question

We are trying to automate our deployment of built android apps to test devices. These range over owned as well as leased devices - which is why we are barred from rooting or flashing. We have multiple build agents able to deploy. We are using ADB over TCP to deal with the deployment because of that.

Readying new devices for app deployment is a big hassle, as we have to connect each device to every build agent (and dev machine) at least once, just to be able to confirm ADB's "trust this device" dialog. We also have some devices that do not have builtin displays and input hardware, for which this is a lot of roundabout work.

Is there a way to:

Connect BuildAgentA to the DeviceA (with USB) and somehow share the trusted adb RSA fingerprints for BuildAgentB&C without having to connect the DeviceA to these build agents at all? So that afterwards, with adb over TCP enabled, we can simply connect and deploy from BuildAgentB to DeviceA.

Limitations:

• We are not able or allowed to root the devices
• We are not able or allowed to flash the devices

Answer 1

You can generate a key pair using

$ adb kill-server
$ mkdir ~/tmp/mykeys
$ adb keygen ~/tmp/mykeys/mykey
$ export ADB_VENDOR_KEYS=~/tmp/mykeys/mykey
$ adb start-server

connect the devices. Then do the same (but copying instead of generating the keys) on other BuildAgents and you should be able to connect to the devices.