HSI DHCP Bug

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Story

We were having trouble receiving messages from the PR2 on computers in the HSI internal network (*.hsi.gatech.edu). It turned out that this is due to HSI computers not being able to resolve the PR2's relative host name (pr2c1, pr2c2, pr2base) into an appropriately qualified name (pr2c1.hsi.gatech.edu, pr2c2.hsi.gatech.edu, etc). This was ultimately caused by GT's DHCP servers telling the HSI computers that their domain name is gatech.edu instead of the correct hsi.gatech.edu. We fixed this ultimately by changing the appropriate DHCP settings but our work around can be found below.

Fix

This fix is here for reference. The best solution is to just change entries in your DHCP server (if you have access to them).

  • You will need to add hsi.gatech.edu to the search domain (in /etc/resolv.conf).
  • We found two ways of doing this in ubuntu:
  • Method 1: Change defaults in /etc/dhcp3/dhclient.conf
    • Open /etc/dhcp3/dhclient.conf
    • Find where the commented out supersede command is and add a new line underneath it: supersede domain-name "hsi.gatech.edu";
    • Save these changes and restart your network stack (disconnect and reconnect through the Ubuntu applet or "sudo /etc/init.d/networking restart"
  • Method 2
    • There is an easy way to do this using the Edit Connections link from the nm-applet. Do the following:
      1. Edit the connection you wish to add the DNS search path to
      2. Choose the IPv4 Settings tab
      3. From the Method drop-down, choose Automatic (DHCP) addresses only
      4. Open a Terminal (Applications - Accessories - Terminal) and find your existing nameservers with the command 'grep nameserver /etc/resolv.conf'.
      5. There will be at least one line returned. Put every IP address from each line into the DNS Servers box as a comma-separated list.
        1. For example, your entry to DNS Servers might look like this: 131.202.3.4, 131.202.1.3, 142.166.145.137, 142.177.2.130, 208.67.222.222, 208.67.220.220
      6. In the Search Domains box, put in the domain names you wish to automatically search as a comma-separated list
        1. For example, your entry to Search Domains might look like this: domain1.com, domain2.org, domain3.edu
      7. Click OK to close the window and save your changes, then click Close to close the Network Connections window.