Troubleshooting Q&A

File system errors on boot

If either the server or student computers are complaining during boot:

  • If the BIOS battery is dead, the clock of the computer will reset on reboot. This causes the filesystem to produce errors because timestamps of files are in the future. Resolution: Replace the BIOS battery on the motherboard.
  • Electrical blackouts may cause unclean shutdowns of file systems. Select the option to fix the hard drive.

If you want information about a file system error, go to maintenance mode and run this command:

# Check all filesystems from /etc/fstab in verbose mode
sudo fsck -A -V

Network problems

Symptom: Clients are not able to connect or boot because of network issues. This typically means that while booting, the computer hangs for several minutes with the Ubuntu logo.

If the server is up, and you know that it is accessible directly from its screen and keyboard, then problems are likely caused by network cables or switches. If all computers are unable to connect, try these options:

  • Make sure network cables are properly plugged in.
  • Check that the switches are on.
  • Use a LAN tester to check cables, especially the one from the server.
  • Check that cables are not causing loopbacks, for instance if a network cable is connected to a switch at both ends.

Blackouts

While installing the server

The installation can be safely resumed and will pick up from where it left. Just boot the default Ubuntu and re-locate and start install.sh, following the normal instructions.

While installing a client

If the installation is disturbed in the first phase, installing the base system (before rebooting the client), then you need to restart “Automatic Ubuntu install”.

If the installation is disturbed after the first reboot, you can do this to save time:

# Press CTRL+ALT+F1
# Log in as teacher
# In the command line after logging in, type...
$ sudo bash
# cd /root
# bash rerun-postinstall.sh