Variable ZoneConfig.SOAConfig.expire

How much time should elapse before the zone is no longer authoritative. This value should be higher than refresh so that a client attempt to refresh its zone data before completely discarding it. Default to 10 blocks, or 100 minutes.

struct ZoneConfig.SOAConfig
{
  // ...
  core.time.Duration expire = Duration(60000000000L);
  // ...
}