Colab as a GPU instance with full SSH access

June 7, 2025 ยท View on GitHub

For users without local GPU resources, Colab is an available solution. It could be transformed into a GPU instance with full SSH access.

This document refers to this tutorial.

Setup sshd

First of all, create a Colab notebook using your Google account and use the GPU runtime mode. Ngrok is used to make ssh forwarding. Before this, please create a password. Then, let's start sshd. Let's setup and run sshd.

! apt-get install -qq -o=Dpkg::Use-Pty=0 openssh-server pwgen > /dev/null
password = "yourpassword"
! echo root:$password | chpasswd
! mkdir -p /var/run/sshd
! echo "PermitRootLogin yes" >> /etc/ssh/sshd_config
! echo "PasswordAuthentication yes" >> /etc/ssh/sshd_config
! echo "ClientAliveInterval 30" >> /etc/ssh/sshd_config
! echo "ClientAliveCountMax 5" >> /etc/ssh/sshd_config
get_ipython().system_raw('/usr/sbin/sshd -D &')

Setup Ngrok

After that, we can install and run Ngrok, which creates a TCP tunnel. You can get authtoken from https://dashboard.ngrok.com/get-started/your-authtoken".

! wget -q -c -nc https://bin.equinox.io/c/bNyj1mQVY4c/ngrok-v3-stable-linux-amd64.tgz
! tar -xvzf ngrok-v3-stable-linux-amd64.tgz
import getpass
authtoken = getpass.getpass("Enter your ngrok authtoken: ")
! ./ngrok config add-authtoken $authtoken
get_ipython().system_raw('./ngrok tcp --region=us --log=stdout --log-format=json 22 > ngrok_log.txt &')

Access your server

Now, You can access your server through ssh command in your local machine. The TCP address and port number can be found through the Ngrok interface https://dashboard.ngrok.com/endpoints.

ssh root@[tcp_address] -p [port_number]

Time consumption on experiments

These experiments are run under the Colab default setting(T4).