Re: localhost pitfall in resolver/solving "Host or domain name not found. Name service error for name=localhost type=A: Host not found" (also type=AAAA)

[Victor Duchovni]

On Thu, May 05, 2011 at 05:58:46PM +0200, Matthias Andree wrote:

> > Do NOT use "[localhost]" as an SMTP nexthop. I always use "[127.0.0.1]".
> > If IPv6 works well for you, you can use "[::1]".
> 
> Hi Victor,
> 
> Why do you recommend so, now that Postfix strips RES_DEFNAMES from
> _res.options by default?  This resolver bug aside :)

You know exactly what you mean when you use "[localhost]" as a nexthop,
why not say so? What's the point of jumping through a pile of indirection
and shared libraries just to arrive at an address that every administrator
knows in advance. In fact, localhost may resolve to both "::1" and
"127.0.0.1", but only one or other is typically correct. 

So I say that this particular "indirection" is counter-productive.
The IPv4 or IPv6 address of localhost is not changing any time soon,
and you just complicate things unnecessarily by using the name.

-- 
        Viktor.