Contents

Setup NFS

We need to connect the student and grading servers via NFS so that the snapshotted student work can be copied to the grading server for grading. Student server is sharing a ZFS volume with grading server, so client is grading server.

Get the client (grading) server IP by ssh’ing on and typing: ip addr show eth0 and you will get an output like this:

Last login: Thu Jan  7 20:11:00 2021 from 206.12.14.102
[centos@dsci-100-instructor ~]$ ip addr show eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9001 qdisc mq state UP group default qlen 1000
    link/ether 02:5d:6f:37:03:a0 brd ff:ff:ff:ff:ff:ff
    inet 222.32.32.222/22 brd 222.11.11.111 scope global dynamic eth0
       valid_lft 3518sec preferred_lft 3518sec
    inet6 fe80::5d:6fff:fe37:3a0/64 scope link 
       valid_lft forever preferred_lft forever

And the IP address is then 222.32.32.222/22.

We then use that IP address in the command below on the student server to add a property called sharenfs on the tank/home filesystem:

sudo zfs set sharenfs='rw=@222.32.32.222/32,crossmnt,no_root_squash' tank/home

The “child” filesystems (e.g. tank/home/dsci100) will inherit this value (unless we override them, but we wont).

To check that this worked type: zfs get sharenfs tank/home and you should see something like:

NAME       PROPERTY  VALUE                                         SOURCE
tank/home  sharenfs  rw=@222.32.32.222/32,crossmnt,no_root_squash  local

Next we need to start the NFS server via:

sudo systemctl enable rpcbind
sudo systemctl enable nfs-server
sudo systemctl start rpcbind
sudo systemctl start nfs-server

From the student server, poke a hole through the firewall by typing:

firewall-cmd --permanent --zone=public --add-rich-rule='rule family="ipv4" source address="<GRADING_SERVER_IP>/32" port port="2049" protocol="tcp" accept'
firewall-cmd --reload

Using the AWS console, edit the security groups of the student server to add NFS with Port 2049, and the grading IP /32.

Then on the grading server create a directory called: /tank-student/home, and then on the student server run systemctl restart nfs-server, and then on the grading server run sudo mount -t nfs <STUDENT_SERVER_IP>:/tank/home /tank-student/home.

Then on the grading server run the code below as a super user (sudo su -) to tell it to mount our NFS share after a reboot:

echo "<STUDENT_SERVER_IP>:/tank/home /tank-student/home nfs defaults 1 2" >> /etc/fstab

Setup ruduax

The Python package rudaux manages the assignment collection, auto- and manual grading, as well as posting grades, solutions and feedback. rudaux needs to be installed and configured on both the student and grading servers.

Setup ruduax on the student server

  1. In the home folder of your student server, clone the rudaux repo

  2. Open the rudaux package folder rudaux/rudaux, and do sudo pip3 install . --upgrade

  3. Install nbgrader & git via sudo pip3 install nbgrader and sudo pip3 install gitpython, and then go to rudaux/dictauth and type sudo pip3 install . --upgrade

  4. Fill out the template rudaux config in rudaux/rudaux/scripts/rudaux_template_config.py and put that in your home folder and rename it rudaux_config.py

  5. Add rudaux to the PATH for root and sudo user. To do this become the super user via sudo su - and then in HOME add rudaux to the PATH in .bash_profile via export PATH="/usr/local/bin:$PATH", and then edit /etc/sudoers so that /usr/local/bin/ is added to the secure_path (it should read: Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin).

  6. In the home folder run sudo rudaux list – this should successfully show you the list of students, tas, instructors, and Jupyterhub assignments

  7. Copy the cron job script rudaux/rudaux/cron/rudaux_snapshot into /etc/cron.d/rudaux_snapshot open it and make sure to replace the /path/to/your/etc/ is your home folder, e.g. /home/stty2u/.

Setup ruduax on the grading server

  1. In the home folder of your grading server, clone the rudaux repo

  2. Open the rudaux package folder rudaux/rudaux, and do sudo pip3 install . --upgrade

  3. Fill out the template rudaux config in rudaux/tests/rudaux_template_config.py and put that in your home folder and rename it rudaux/tests/rudaux_config.py

  4. Install nbgrader & git via sudo pip3 install nbgrader and sudo pip3 install gitpython, and then go to rudaux/dictauth and type sudo pip3 install . --upgrade

  5. Add rudaux to the PATH for root and sudo user. To do this become the super user via sudo su - and then in HOME add rudaux to the PATH in .bash_profile via export PATH="/usr/local/bin:$PATH", and then edit /etc/sudoers so that /usr/local/bin/ is added to the secure_path (it should read: Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin).

  6. Open up your /srv/jupyterhub/jupyterhub_config.py file remove any LTAuthenticator lines and replace with

    c.JupyterHub.authenticator_class = 'dictauth.DictionaryAuthenticator'
c.DictionaryAuthenticator.encrypted_passwords = {}

  7. In the home folder, type sudo dictauth list_users – should output an empty list

  8. Still in the home folder, run sudo dictauth encrypt_password and follow the on-screen instructions this will spit out a hash and a salt then do sudo dictauth add_user --user tiffany --digest [the_big_hash_string] --salt [the_big_salt_string]. Restart the JupyterHub: sudo systemctl restart jupyterhub.

  9. Now go in your web browser to www.your-jupyterhub.domain.com and you should see the login screen – login with your username and password (make sure you can’t login with another username and password).

  10. Go back and do the sudo rudaux list step and make sure that works

  11. Copy the cron script rudaux/rudaux/cron/rudaux_manage into /etc/cron.d, and make sure to fix the pathname to be your home folder with the rudaux config file

  12. Create a set of SSH keys to use to authenticate into the Instructor GitHub repository:

    sudo su
cd /root/.ssh
ssh-keygen # do not add a passphrase
vim id_rsa.pub

  13. Copy that public key to settings/deploy keys in whatever repo you want to give read access to (don’t give it write permission, no need for that). rudaux runs as root, so you need to look in root’s user folder for the public key (no need to have multiple keys)

  14. Finally run sudo rudaux run on the command line in your home folder and it’ll 1) give students an automatic extension for late reg assignments – it will create overrides on canvas, and 2) run the autograding workflow for all submissions that are past due.

Add JupyterHub as an App on Canvas Setting up Assignments on Canvas