Network/Troubleshooting/DNS

We have experienced a number of issues in the past with home internet providers not correctly handling DNS resolution for UMIACS hostnames. This can affect connectivity to UMIACS.

In the face of this, here are a few last-resort options for bypassing problematic DNS services.

Google DNS

IP Addresses:

• 8.8.8.8
• 8.8.4.4

OpenDNS

IP Addresses:

• 208.67.222.222
• 208.67.220.220
• 208.67.222.220
• 208.67.220.222

How to change your default DNS servers

• Windows:

1. Go to Control Panel -> Network and Internet -> Network and Sharing Center.
2. Click "Change adapter settings" on the left.
3. Right click on the network adapter you're using, choose "Properties" from the context menu.
4. Select "Internet Protocol Version 4 (TCP/IPv4)" and click on the "Properties" button.
5. If not selected, choose "Use the following DNS server addresses:"
6. Enter the public DNS addresses you desire to use.
7. Click OK, and close the remaining windows.

• macOS: System Settings > Network > Wi-Fi/Ethernet > Details > DNS

• Linux: Edit your /etc/resolv.conf file and change the IP addresses after "nameserver" to any of those listed above.

Manual Lookup

If you are having problems getting to UMIACS hosts, you can use our name servers to resolve those specific host names and then connect using the IP addresses you lookup. Our name servers are 128.8.120.19, 128.8.120.50, and 128.8.132.75. To use this information to get the IP address of the host somehost.umiacs.umd.edu, you would use the command nslookup somehost.umiacs.umd.edu 128.8.120.19, from a Windows, macOS, or Linux command prompt / terminal.