Between Tuesday, September 19 and Thursday, October 12, 2023, CIT Identity Management will be upgrading some of the domain controllers for the cornell.edu Active Directory domain.

The upgrade process will involve decommissioning one domain controller at a time and replacing it with a new domain controller with same name and IP address. This work on each controller will be performed during business hours and is expected to be completed the same day. No service outage is anticipated, as the change will affect only one domain controller at a time. However, if an application or service is configured to use a single domain controller, that application or service might be impacted when the specific domain controller is being worked on.

Please be mindful of the maintenance dates below and plan to change your configuration to use another domain controller before the planned maintenance:

• Tuesday, 9/19/23: AD9
• Thursday, 9/21/23: AD10
• Tuesday, 9/26/23: AD2
• Thursday, 9/28/23: AD3
• Tuesday, 10/3/23: AD4
• Thursday, 10/5/23: AD5
• Tuesday, 10/10/23: AD19
• Thursday, 10/12/23: AD20

If you are using any of the DNS round-robin names, such as query.ad.cornell.edu, awsquery.ad.cornell.edu or azquery.ad.cornell.edu, no action is required as CIT will update these records to exclude the domain controller before starting maintenance. We don't anticipate any impact, but just be aware that this will be done before the change.

If you experience any issues with Active Directory during the maintenance due to decommissioning a domain controller, please contact the IT Service Help Desk.