Most ISP's dns cache servers honor the TTL defined in the
authoritative SOA records, unless is 1 minute or less.
I think the average TTL time for a dns zone would be
measured in minutes. It needs to be that low in order to
do SRV load-balancing, A/B testing, etc.
In any case, in the highly unlikely event that they manage
to overload the 13 servers, there's plenty of time for
every domain to temporarily extend the TTL on March 31.
I think the average TTL time for a dns zone would be measured in minutes. It needs to be that low in order to do SRV load-balancing, A/B testing, etc.
In any case, in the highly unlikely event that they manage to overload the 13 servers, there's plenty of time for every domain to temporarily extend the TTL on March 31.