Your first Jetstream2 VM: create, connect, work, shelve

UCR researchers with an ACCESS project that has Jetstream2 (CPU) time

You need an ACCESS project with Jetstream2 (CPU) time. If you do not have one, start with the researcher guide and KB009.

Go to jetstream2.exosphere.app.
Click Add allocation, then Add ACCESS Account.
At the CILogon page choose ACCESS CI (XSEDE) and sign in with your ACCESS username and Duo.
Your ACCESS projects that have Jetstream2 time appear on the home page. Click one.

The allocation page shows how many SUs you have left for each resource, your instances, volumes, public IP addresses and SSH keys:

Exosphere allocation overview: SUs remaining for CPU, GPU and large-memory instances, and cards for instances, volumes, shares, public IP addresses, SSH keys and images

2. Make an SSH key (once per computer)

The web shell and web desktop work without a key, but SSH from your own computer needs one. On macOS or Linux (or Windows PowerShell):

ssh-keygen -t ed25519 -C "my-laptop-jetstream2" -f ~/.ssh/jetstream2
cat ~/.ssh/jetstream2.pub

Copy the single line that starts with ssh-ed25519. That is the public key, and it is safe to paste into Exosphere. Never share the file without .pub.

3. Create the VM

Click Create, then Instance.
Choose an image. Ubuntu 24.04 (latest) is a good default.
Give it a name and pick a flavor. m3.quad (4 cores, 15 GB RAM, 4 SUs per hour) is roughly a mid-range laptop. The bars show how much of your allocation's quota is in use.
Scroll down:
- Enable web desktop? Choose Yes if you want a graphical desktop in the browser.
- Choose an SSH public key. Pick yours, or click Upload a new SSH public key, give it a name, paste the ssh-ed25519 ... line and click Create.
Leave Advanced Options as they are (operating system updates on, automatic public IP address), and click Create.

The VM shows Building, then Running Setup, then Ready. In our test this took about five minutes.

The instance list with two Ready instances, their flavors, and Connect to and web desktop buttons

4. Connect

Click the VM's name to open its page. Interactions lists the ways in, and Credentials gives the hostname, public IP address and username (exouser).

Instance page: Interactions (web shell, web desktop, native SSH, console) and Credentials (hostname, public IP, username exouser, SSH key name)

Web shell (no setup)

Click Web Shell. A terminal opens in a new browser tab, already logged in as exouser.

Web desktop

Click Web Desktop for a full Ubuntu desktop in the browser, with Firefox, a terminal, RStudio and MATLAB in the dock:

Ubuntu desktop in the browser, showing an 'upgrade available' prompt

If Ubuntu offers to upgrade to a new release, click Don't Upgrade. Release upgrades on a VM can break the Jetstream2 setup; make a new VM from a newer image instead.

SSH from your computer

Copy the Native SSH line from the instance page, adding your key:

ssh -i ~/.ssh/jetstream2 exouser@<public-ip>

To save typing, add an entry to ~/.ssh/config:

Host my-js2
  HostName <public-ip>
  User exouser
  IdentityFile ~/.ssh/jetstream2

Then ssh my-js2, and scp results.csv my-js2: to copy a file across.

5. Look around and install software

These are the commands we ran on a fresh m3.quad, with what they returned:

cat /etc/os-release | head -1   # PRETTY_NAME="Ubuntu 24.04.5 LTS"
nproc                           # 4
free -h                         # about 14 GiB total
df -h /                         # 19 GB root disk
sudo -n true && echo ok         # ok: you have sudo

Ubuntu packages:

sudo apt update
sudo apt install -y htop tmux

Docker is already installed:

sudo docker run --rm hello-world

Python (3.12) with a virtual environment, for example JupyterLab:

python3 -m venv ~/jl
~/jl/bin/pip install jupyterlab
~/jl/bin/jupyter lab --version

The Jetstream2 software collection is loaded with modules:

module avail                 # R, apptainer, intel-oneapi, matlab, miniforge, nvhpc, rstudio ...
module load miniforge        # gives you conda
module load apptainer        # Singularity/Apptainer containers

Keep long jobs running after you disconnect with tmux: start tmux, run your work, press Ctrl-b then d to detach, and later tmux attach to return.

6. Shelve it when you stop

A running VM uses SUs every hour, even when idle. When you finish for the day or the week, open the VM's page, choose Actions, then Shelve, and confirm. Shelving shuts the VM down and keeps its disk. Unshelve brings it back; check the instance page for its address afterwards.

More on shelving, sizes, volumes and deleting: Managing Jetstream2 VMs and SUs.

7. If something goes wrong

Permission denied (publickey): the key you pass with -i is not the one chosen when the VM was created. Use the web shell instead, and add your key to ~/.ssh/authorized_keys on the VM.
Host key changed warning after a VM was rebuilt or given a new address: remove the old entry with ssh-keygen -R <public-ip>.
No public IP address: Jetstream2 has warned that public IPv4 addresses are scarce. The web shell and web desktop still work without one.
Anything else: help@jetstream-cloud.org, or contact Research Computing.

Owner: Research Computing Reviewed: 30 Oct 2026