On Wed Aug 16 between 5:00-7:00am, the authoritative DNS server dns3.illinois.edu will be migrated to a new subnet within AWS, and its IPv6 address will change from 2600:1f16:8b2:2e01::53 to 2600:1f16:8b2:2e53::53. Its public IPv4 address (3.16.92.183) will not change.
No customer action is required, except for a very few customers with IPv6 DNS Traffic Control Server targets that receive health monitor requests from dns3. Those customers have already been notified separately.
dns3 will experience an outage during this change window, but dns1 and dns2 will remain up; there will be no interruption to DNS service as a whole.
The EDUCAUSE "glue" AAAA record for dns3.illinois.edu (published with a 2-day TTL we can't modify) will be updated to reflect the new IPv6 address immediately after the server has been migrated. For the next two days, some recursive DNS servers may still send initial queries to the old address of dns3 (which will time out), but once they obtain and cache dns3's new authoritative AAAA record from dns1 or dns2, they will be able to use the new address to query dns3 as well.
Q: What is the benefit of this change?
A: Placing dns3.illinois.edu on a dedicated subnet provides us with more tools to use when responding to denial-of-service attacks against our authoritative DNS.
Please contact hostmgr with any questions or feedback.