In an effort to further secure and reduce the complexity of University of Michigan networks, ITS has been working with units to change the IP addresses of U-M’s DNS resolver servers from public to private IPs. At the halfway mark, approximately 70% of systems have transitioned to new DNS resolver addresses. By early April, ITS DHCP (Dynamic Host Configuration Protocol) will transition. After ITS DHCP has transitioned, the remaining hosts will be those requiring manual DNS configurations. The project scope includes all systems on the U-M Ann Arbor campus configured to use the current nine (9) DNS resolver addresses.
Current DNS resolver addresses:
- 141.211.125.15 – Originally an authoritative DNS server
- 141.211.125.16 – Originally Restricted to Data Centers
- 141.211.125.17 – Originally South/Central Campus
- 141.211.144.15 – Originally an authoritative DNS server
- 141.211.144.16 – Originally Restricted to Data Centers
- 141.211.144.17 – Originally North Campus
- 141.212.2.69 – Originally College of Engineering Server
- 141.212.2.81 – Originally College of Engineering Server
- 141.213.73.83 – Originally College of Engineering Server
New private IP addresses for DNS resolver servers:
- 10.10.10.10 – Primary DNS resolver address
- 10.10.5.5 – Secondary DNS resolver address
To assist units in checking which hosts are using the new DNS resolver IP Addresses and which still need to be updated, ITS has developed a DNS Resolver Check Tool and step by step instructions for using the tool. This tool has been created specifically for this effort and will not be available after completion of this project.
