ITS Service Status Report

Scheduled Maintenance — Canceled

Decommission Public DNS Resolver IP Addresses

Services Affected: Decommission Public DNS Resolver IP Addresses

Start Time: 10/31/2017 7:00 am

Issue Symptoms: Inaccessible

On February 24, 2018, ITS will turn off the nine (9) public IPs for the public DNS resolvers. At that time all systems must be configured to the new private IP addresses (listed below) in order to continue to use ITS DNS resolver services. It is believed that less than .5% of U-M systems leveraging ITS DNS resolver services still need to be updated.
New private IP addresses for DNS resolver servers:
- 10.10.10.10 - Primary DNS resolver address
- 10.10.5.5 - Secondary DNS resolver address


Of the 175,000+ systems at U-M that have already converted to the new private IP addresses, no further change is necessary. For the remaining systems who have not updated their DNS address settings, these systems must update their DNS address settings by February 24th in order to continue to operate on the network and access the internet as they do today.

Technical Comments and Resolution Notes:

The following IP addresses will no longer provide DNS resolution services after February 24th. Any systems that have any of the following addresses in their DNS resolver configuration settings must change to the new addresses by February 24th. Systems continuing to use the following addresses will be redirected to a landing page informing them the address is no longer valid for DNS resolution services.


- 141.211.125.15
- 141.211.125.16
- 141.211.125.17
- 141.211.144.15
- 141.211.144.16
- 141.211.144.17
- 141.212.2.69
- 141.212.2.81
- 141.213.73.83

Technical Details

Service Type: Production

Server Name: Central DNS Resolvers

Comments:

As announced a year ago, we will be turning off the old DNS Resolver IP 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
https://docs.google.com/document/d/1CgaspoGqh3v8gof7xK6fYv6O03NNVhHTdvnMzlTpQq8/edit

Ann Arbor campus computers should use the new IP's:
10.10.10.10
10.10.5.5

Except the 35.0.x.x guest networks, which should use:
35.0.0.12
35.0.0.4

For UMHS - ask HITS

For ilab (network engineering)
198.111.225.138
198.111.225.133

Pellston and Michigania
198.110.84.250
207.74.194.250

For the BIN network - use Google or OpenDNS, like:
8.8.8.8
8.8.4.4

Dearborn, Flint, Detroit, etc - ask local IT support

Off-campus - use your local ISP, or Google, or OpenDNS, etc.

Groups Notified:

Report Additional Impacts

Contact the ITS Service Center for more information or to report additional impacts.