Scheduling with TinyDNS
One of TinyDNS' greatest strengths is the ability to schedule changes. When you have an environment of ~100,000 entries with 100s of them changing daily, this is essential.
Even if your environment is much smaller or more static, this feature can still be invaluable. For example, let’s say that you need to move data centers, your public address will change. At the time of the cut over, you want the whole world to move with you at the same time not over the course of hours or days depending on caches.
If you schedule the change for a week out, TinyDNS will start a countdown and for every request for the old address, the TTL will be set to 3600 seconds, or 1 hour. In the last hour, any requests for your address will be prorated so that everyone will be forced to check in at the time of the change over. In other words, when there is 50 minutes left, the TTL handed out will be 50 minutes. When there are 12 minutes left, the TTL is 12 minutes.
After the scheduled time, the TTL handed out will be whatever you set the record for, or, 3600 if you left it to the default.
Here is a link to a tool I wrote about that makes creating the timestamps very easy.