[RLUG] migrating ISP connections for machine running DNS and SMTP servers

[Anna]

On Wed, Oct 18, 2006 at 11:00:43AM -0700, John Dell wrote:
> Just remember that you need to make the TTL changes well before you make the actual A/MX record changes.
> 
> The time in advance depends on your current TTL (usually 48 hours). Unfortunately, there are alot of broken DNS servers that don't properly honor your TTL and will cache for a longer period of time.
> 
> Given that, it is best to change your TTL to a short value (3600 seconds) at least a week in advance of changing an IP address.

luckily my TTL was already set to a 24 hours.  I think that should be
good enough.

Thanks,

- Anna