[CentOS] OT: free DNS service?

[John Doe]

From: R-Elists <lists07 at abbacomm.net>
> > I have been using a free DNS service for the past seven (7) years.
> > This morning, at 4 A.M., ,  I changed the "A" record for one 
> > of my web sites,  to point to an IP address on a different 
> > server, so I could test. After watching the TTL count down 
> > from 3600 to zero, with the "dig" command,  it then reset to 
> > 3600, but still resolved to the
> > original IP address.  :-)   I set the "A" record back to the original
> > IP address and  filed a Support Ticket with that company, but 
> > if they cannot get this to work properly again, I need a new 
> > DNS service that is free. Recommendations?  (BTW, the Domain 
> > is registered with GoDaddy, but not hosted there, so it 
> > appears I cannot use their "Total DNS" service).  TIA!
> so, when you make a dns change properly on a serving system, it still has to
> get distributed and that doesnt mean that every machine that has a resolver
> or cache has changed at that instant... it can take more time than you
> expecetd...

Indeed; there is a TTL parameter.
If you want the changes to be propagated 'fast', you set the TTL to a low duration.
But DNS caches can bypass it if they choose to...

JD