[NTLUG:Discuss] why does the web site cannot be 'see' from outside (internet)?

[Greg Edwards]

m m wrote:
> 
> 
> the problem still happend even I can see the ip A record changed (which 
> means that Public DNS _really_ updated my A record)
> 
> How/what the problem will happen if the serial number don't change?
> How TTL works on DNS on real world?
> 
> 
>>
>> Is it possible that the DNS was not reloaded or not updated in a 
>> reasonable period so the new IP was not broadcast for awhile?
> 
> at where? on my box? not quite understand this one.
> 

A change in the serial number will force an expire of a record even if 
the TTL has not expired.  Just cause you change the values in a DNS file 
does not mean that named will read them.  If your admin does not change 
the serial number or does not tell named to re-read the files no new IPs 
will get sent out to the world.

-- 
Greg Edwards