Month: April 2025

Use android emulator running on a different machine for debugging

I haven’t previously tried (or even noticed) the adb connect command that cmb mentioned, but I can confirm that forwarding the TCP ports yourself — such as over SSH — works fine.

The emulator listens on two TCP ports per instance: 5554 for the telnet interface and 5555 for control communication with tools like DDMS. So you could probably get away with only forwarding port 5555 (though I’ve only tried it so far with both). Each subsequent emulator takes the next available even+odd port number tuple (up to around 5580, I think).

Run the avd using emulator or android studio (AS) on the remote machine where only emulator and avd is needed. AS is only optional

./emulator -avd avd-name -accel on -gpu on

Run the below command on the machine where you have android studio and you are coding and debugging. Before this command, 

ssh -NL 5554:localhost:5554 -L 5555:localhost:5555 myuser@remote-serverCode language: CSS (css)

Then kill the local adb-server , so that it restarts and starts to see open ports 5554 and 5555 on local host and assume that this is a local emulator. After that you can list adb devices to see if new emulator is visible, otherwise AS will itself show the new devices in the devices section of the IDE

adb kill-server<code>killall adb</code><code>adb device</code>Code language: HTML, XML (xml)

I believe the emulator tries to notify a local adb server at startup; hence the need to restart adb in order for it to probe the local 5554+ ports.

Note that the localhost in the ssh command refers to the local interface of the remote machine.

adb devices showed a new emulator — emulator-5554 — and I could use it as if it were running on my local machine

References

https://stackoverflow.com/questions/1754162/remote-debugging-with-android-emulator

SSH login to remote machines without repeatedly giving password

ssh-keygen -t rsa -b 4096 -C "your-email@example.com"Code language: JavaScript (javascript)

On your local machine (the one you’ll be SSH-ing from), open a terminal and run the above command. Optionally, you can set a passphrase, but if you want it fully passwordless, leave it blank and press Enter.

Now, copy your SSH key to the remote machine (the computer you’re SSH-ing into). This step allows the remote computer to recognize your key and authenticate you automatically.

Run this command (replace username and remote_host with your remote machine’s username and IP address or hostname):

ssh-copy-id username@remote_hostCode language: CSS (css)

This will copy your public key (~/.ssh/id_rsa.pub) to the remote machine’s ~/.ssh/authorized_keys file

If ssh-copy-id is not available on your system, you can manually copy the key:

cat ~/.ssh/id_rsa.pub | ssh username@remote_host 'mkdir -p ~/.ssh && cat >> ~/.ssh/authorized_keys'Code language: JavaScript (javascript)