RFC 1912 define a valueset between 20 minutes and 12h, but I have never seen a system with values under 1h (perhaps because a few systems ignores values under 1h).
I've never seen a system ignoring the TTL. TTL below 20 minutes is not uncommon, e.g. all dyndns-services use very short TTLs, e.g. 60 seconds. This is not a problem at all.
Regards Michael
I have done a simple check and it seems both www.dyndns.com and freedns.afraid.org give 1 min TTLs.
It's strange you can't change that value (a way of avoiding too much load?) I guess we could workaround it by cnameing to some of their domains several hours before the move though it seems a bit egoistic.
Just as a reference, i prefer the later system as it doesn't have profit, much on the good free way.
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