Virtual Exam

Please read the documentation of virtual exam

The way the virtual exam white listed software (etc/vx.conf) will be rewritten early in Term 1 to better cope with software changes on CSE computers.

Useful scripts

• ~give/stable/bin/prac_install_vx <prac_name>

  • set up a standard virtual exam environment
• priv passwd
• change the vxN password before and after the exam with this script
• add the class account public key to the exam account

• priv chown <path_wildcard>

• change work directory ownership from 90<uid> to the exam account

• needed for access to students' files
• after changing ownership, students can't start up the exam. so, do this only after the exam has finished.
• ~give/stable/bin/vx-conf-product.pl
  • strace the command
  • feed the output of strace to this script
  • add vx.conf files as arguments
• script will output the files that are missing from the config files
• dpkg-query, apt-cache depends

Tips

• when the exam crashes after you authenticated with your zid, check the stderr.log file under <exam_account>/var directory. Look at the latest directories.

  marimba % ls -lt ~/var | head -5
  total 988
  drwxr-xr-x 2 cs9024exam cs9024exam 4096 Feb 13 06:59 marimba-25528
  drwxr-xr-x 2 cs9024exam cs9024exam 4096 Feb 12 20:49 wagner-7800
  drwxr-xr-x 2 cs9024exam cs9024exam 4096 Feb 12 20:33 vx4-45795
  drwxr-xr-x 2 cs9024exam cs9024exam 4096 Feb 12 18:39 vx4-34624

• after changing ownership of the work directories to exam account, you can't start up the exam with the same work directories. create a new work directory.

  cd ~/exams/18s2supp
  mv work work.19dec
  mkdir work
  chmod 1777 work