Re: pg_service.conf

On Feb 19, 2006, at 10:59 AM, Mark Woodward wrote:

>> "Mark Woodward" <pgsql(at)mohawksoft(dot)com> writes:
>>
>>> DNS isn't always a better solution than /etc/hosts, both have
>>> their pros
>>> and cons. The /etc/hosts file is very useful for "instantaneous,"
>>> reliable, and redundent name lookups. DNS services, espcially in
>>> a large
>>> service environment can get bogged down. 20,000 hosts doing a lot of
>>> lookups can require a dedicated single point of failure. OK, so
>>> you add
>>> two DNS machines and load balance across them with a fault tollerant
>>> load
>>> balancer, how many thousands of dollars? For how much information? A
>>> simple "clustercpy -f targets pg_service.conf /etc" would save
>>> thousands
>>> of dollars, increase efficiency, increase reliability, decrease
>>> electrical
>>> costs, etc.
>>
>> Um, is there something wrong with having multiple DNS servers in
>> resolv.conf? Other than having to time out on #1 before you try #2?
>> I'm genuinely curious.
>
> What is the "timeout" of that DNS lookup, before it goes to the
> second DNS
> server?

Depends on the resolver you use. Often the "timeout" is zero. Other
times
it's adaptive, depending on history of response time from the servers.

Except in the case of horrible misconfiguration, it's rarely a problem.

Cheers,
Steve