ssh reverse tunnel into colab VM.ipynb

ssh-reverse-tunnel-into-colab-vm.ipynb

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  "metadata": {
    "colab": {
      "name": "ssh reverse tunnel into colab VM.ipynb",
      "provenance": [],
      "collapsed_sections": [],
      "authorship_tag": "ABX9TyN6wTZ5owaJGgw+kx7loePb",
      "include_colab_link": true
    },
    "kernelspec": {
      "name": "python3",
      "display_name": "Python 3"
    }
  },
  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "view-in-github",
        "colab_type": "text"
      },
      "source": [
        "<a href=\"https://colab.research.google.com/gist/shadiakiki1986/4aa8f128d816f31203e05fb8fbc2fabf/ssh-reverse-tunnel-into-colab-vm.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "wYEvw5BrRhFf",
        "colab_type": "text"
      },
      "source": [
        "This notebook illustrates how to use a ssh reverse tunnel [1] in order to ssh into a google colab VM.\n",
        "It was inspired by the ssh forward tunnel idea from [2].\n",
        "\n",
        "ssh'ing into a google colab VM is useful to monitor GPU usage with `nvtop` while some GPU-based code is running.\n",
        "Of course, it's also useful for running stuff in parallel in different screen sessions with `screen`,\n",
        "but that's not really the goal of colab, and you're better off just renting your own VM on AWS.\n",
        "\n",
        "\n",
        "Figure 1 shows what the configuration looks like for a forward tunnel\n",
        "\n",
        "```\n",
        "Fig 1\n",
        "colab ---> ngrok + sshd ---> public IP\n",
        "                                 ^\n",
        "                                 |\n",
        "                                 |--- ssh <--- local machine\n",
        "```\n",
        "\n",
        "Figure 2 shows what the configuration looks like for a reverse tunnel\n",
        "\n",
        "```\n",
        "Fig 2\n",
        "colab ---> sshd + ssh reverse tunnel ----|-|\n",
        "                                         | |\n",
        "                                         v ^\n",
        "                                      public IP <--- sshd+ssh <--- local machine\n",
        "```\n",
        "\n",
        "If local machine does not already have a public IP, then use ngrok or equivalent to get one.\n",
        "\n",
        "Note that this requires sshd to be running on the local machine as well.\n",
        "\n",
        "References:\n",
        "\n",
        "[1] https://www.howtogeek.com/428413/what-is-reverse-ssh-tunneling-and-how-to-use-it/\n",
        "\n",
        "[2] https://stackoverflow.com/questions/48459804/how-can-i-ssh-to-google-colaboratory-vm#48465924"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "20oFfIHGTLss",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 751
        },
        "outputId": "8e5ccce2-8627-424f-f3c1-1786b2ca4871"
      },
      "source": [
        "#Setup sshd\n",
        "# Will yield the below messages, but doesn't matter since we launch sshd manually below\n",
        "# > invoke-rc.d: could not determine current runlevel\n",
        "# > invoke-rc.d: policy-rc.d denied execution of start.\n",
        "! apt-get install -qq -o=Dpkg::Use-Pty=0 openssh-server > /dev/null\n",
        "\n",
        "#Set root password\n",
        "! mkdir -p /var/run/sshd\n",
        "! echo \"PermitRootLogin yes\" >> /etc/ssh/sshd_config\n",
        "\n",
        "# some configurations for GPU stuff\n",
        "! echo \"LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/lib64-nvidia\" >> /root/.bashrc\n",
        "! echo \"export LD_LIBRARY_PATH\" >> /root/.bashrc\n",
        "\n",
        "#Run sshd\n",
        "!/usr/sbin/sshd # will daemonize\n",
        "!ssh-keygen -f ~/.ssh/id_rsa -t rsa -N \"\"\n",
        "print(\"\"\"Copy below public key to local machine with:\n",
        "echo '...' >> .ssh/authorized_keys (replace ellipsis with value below)\"\"\")\n",
        "!cat ~/.ssh/id_rsa.pub\n",
        "input(\"Press Enter to continue...\")\n",
        "\n",
        "# get local machine public key\n",
        "!echo \"Copy public key from local machine (cat ~/.ssh/id_rsa.pub)\"\n",
        "import getpass\n",
        "local_pubkey = getpass.getpass()\n",
        "!echo $local_pubkey >> /root/.ssh/authorized_keys\n",
        "\n",
        "# get local machine public IP and username\n",
        "!echo \"Public URL for local machine:\"\n",
        "local_puburl = input()\n",
        "!echo \"Username for local machine:\"\n",
        "local_username = input()\n",
        "sshcmd = \"ssh -fN -R 43022:localhost:22 -T -o StrictHostKeyChecking=no $local_username@$local_puburl\"\n",
        "get_ipython().system_raw(sshcmd)\n",
        "\n",
        "print(\"\"\"You can ssh into colab VM from the local machine with:\n",
        "ssh -p 43022 root@localhost\n",
        "\n",
        "Note that 'root' is the username on the colab VM, not on the local machine\n",
        "\"\"\")"
      ],
      "execution_count": 1,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "\n",
            "Creating config file /etc/ssh/sshd_config with new version\n",
            "Creating SSH2 RSA key; this may take some time ...\n",
            "2048 SHA256:oCYF7Dh1VNX+vMuz+hFEq1pX1HEwLh49PVp3RAjr6nA root@1b9999f733b0 (RSA)\n",
            "Creating SSH2 ECDSA key; this may take some time ...\n",
            "256 SHA256:v9lN+ZewaJ6M3PRbA5jQyshEBTCpZ+Ndr+RPwbjcsc8 root@1b9999f733b0 (ECDSA)\n",
            "Creating SSH2 ED25519 key; this may take some time ...\n",
            "256 SHA256:yulUjevATlpCnQkQNn81mIY7oFDaDiZtgsHVjtBp2L8 root@1b9999f733b0 (ED25519)\n",
            "Created symlink /etc/systemd/system/sshd.service → /lib/systemd/system/ssh.service.\n",
            "Created symlink /etc/systemd/system/multi-user.target.wants/ssh.service → /lib/systemd/system/ssh.service.\n",
            "invoke-rc.d: could not determine current runlevel\n",
            "invoke-rc.d: policy-rc.d denied execution of start.\n",
            "Generating public/private rsa key pair.\n",
            "Created directory '/root/.ssh'.\n",
            "Your identification has been saved in /root/.ssh/id_rsa.\n",
            "Your public key has been saved in /root/.ssh/id_rsa.pub.\n",
            "The key fingerprint is:\n",
            "SHA256:Xk0XVs81HnDddZOJ/Yk0juBCwYJ9rxdvH8hzRFJ4WiY root@1b9999f733b0\n",
            "The key's randomart image is:\n",
            "+---[RSA 2048]----+\n",
            "|    o ...   oo**@|\n",
            "|   . o + . E Xo*X|\n",
            "|      + o . & +.=|\n",
            "|       . + = = ..|\n",
            "|        S = +    |\n",
            "|       o o * o   |\n",
            "|        o . + .  |\n",
            "|             .   |\n",
            "|                 |\n",
            "+----[SHA256]-----+\n",
            "MANUALLY copy below public key to local machine with:\n",
            "echo '...' >> .ssh/authorized_keys (replace ellipsis with value below)\n",
            "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCvHGAUhNaIoSLocLBgIh0fxQB3YqoS+1MeEAkCeafrRTBgKqsCSu69q9c4l2fjJ2bgt+rTwTuk3l7z4/GhWIdaZbyENPSZmpj3XOxpwuMV9n1Jw6YIbcCdoNBXnUoDcrMQJCVn/vi4AnIGnBo3p9z+sUWgV/uS1kNjvMtk9JoY6vUWfPXDd/c3B+OfEoP2dIH463N4kQwqF8Be83Y8b0wfYMmpKlIQS2yPwiUMP1/ZvFa0QMb5rZb0uN4oRCftHCVUrcv8JOx0Vx+A/t9HYa8YkldY3EBq9p+US1GUG9wjP5dnTJlBHNtNSLoLZx2up0eMGIxOc18Y3A36ty8+0zJZ root@1b9999f733b0\n",
            "Press Enter to continue...\n",
            "MANUALLY copy public key from local machine (cat ~/.ssh/id_rsa.pub)\n",
            "··········\n",
            "Public URL for local machine:\n",
            "bioinfo.lau.edu.lb\n",
            "Username for local machine:\n",
            "shady.akiki\n",
            "You can ssh into colab VM from the local machine with:\n",
            "ssh -p 43022 root@localhost\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "jG8uMRYKU-hs",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 68
        },
        "outputId": "285a61b3-7bec-449a-fecf-675ae4c0a293"
      },
      "source": [
        "# kill some daemon processes if needed to restart them\n",
        "#!kill -9 855\n",
        "#!ps aux|grep ssh\n",
        "#!ps aux|grep ngrok\n",
        "#!ps aux|grep sshd"
      ],
      "execution_count": 14,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "root         695  0.0  0.0  95524  5144 ?        Ss   05:34   0:00 /usr/sbin/sshd\n",
            "root        1160  0.0  0.0  39192  6544 ?        S    05:56   0:00 /bin/bash -c ps aux|grep ssh\n",
            "root        1162  0.0  0.0  38572  5024 ?        S    05:56   0:00 grep ssh\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "gwmygh_ve9Ya",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 198
        },
        "outputId": "10ed9f45-472f-4db3-cc23-4df2e407a5d5"
      },
      "source": [
        "# run \"top\" in ssh session and see usage\n",
        "for i in range(1, 1000000000):\n",
        "  pass"
      ],
      "execution_count": 11,
      "outputs": [
        {
          "output_type": "error",
          "ename": "KeyboardInterrupt",
          "evalue": "ignored",
          "traceback": [
            "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
            "\u001b[0;31mKeyboardInterrupt\u001b[0m                         Traceback (most recent call last)",
            "\u001b[0;32m<ipython-input-11-d776bd0c47e6>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m# run \"top\" in ssh session and see usage\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0;32mfor\u001b[0m \u001b[0mi\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;36m1000000000\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      3\u001b[0m   \u001b[0;32mpass\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
            "\u001b[0;31mKeyboardInterrupt\u001b[0m: "
          ]
        }
      ]
    }
  ]
}