For something relatively simple like modifying a single record to a domain, it might feel like overkill to have a “plan” or “strategy” – but given the very public severity of screwing up DNS some caution is warranted. It’s like the old saying: “A packet of prevention is worth a pound of cure.”
There’s a simple way to limit your mistakes: never update both a DNS record and a TTL for that record at the same time. Ideally you’ll have a process of:
- Drop TTL on the DNS record to something very low a couple of days before you actually need to make the switch. Ex: 300 seconds
- Change the actual record on your cutover date.
- Several days after you’ve made the switch, up the TTL to something higher.