Troubleshooting Network Connections

Tips to discover the problem

• Release and renew your IP settings (DHCP lease).
• Temporarily disable any personal firewall software (Windows Firewall, iptables, etc.).
• If you have a wireless card (or another network card), disable it.
• Make sure your DNS servers are 128.128.243.3 and 128.128.243.2.
• Try pinging each of the following: your gateway (router) address, 128.128.76.85, and www.whoi.edu. If any of those work, you have some IP network connectivity.
• On Windows computers, check for spyware with Microsoft AntiSpyware, Lavasoft Ad-Aware, and/or Spybot Search & Destroy and viruses with Norton Anti-Virus.
• If you are able to access WHOI sites but cannot get to reliable outside sites such as Google, Yahoo you may be blocked from accessing the Internet. Call the Helpdesk at x-2439.
• If you are able to access most network resources but not one in particular, the problem may be with the server you are trying to access. Verify that the server is working and look for server-side IP restrictions (tcpwrappers, access control lists, firewall rules, etc.)
• Call the CIS Helpdesk at x-2439.. Be prepared to provide your IP address, hardware (MAC) address, and Ethernet jack number.

You may find this troubleshooting flowchart (PDF) to be helpful.