spf?

[Roger Oberholtzer]

On Mon, 1 Mar 2004 09:21:41 -0500
dep <dep at linuxandmain.com> wrote:

> quoth Net Llama!:
> | On Mon, 1 Mar 2004, dep wrote:
> | > greetings, crowd . . .
> | >
> | > time for me to undertake another breathtaking display of ignorance.
> | >
> | > i'm on a cable modem and have used sendmail for the most part for
> | > years. problem is, more and more isps are blacklisting whole blocks
> | > of cable modem addresses.
> | >
> | > what i'm trying to figure out is whether spf would be of any use
> | > here, on my machine, or whether it is something that, really, has
> | > nothing to do with me. i've endeavored to read what i can on the
> | > subject, but most of it is, like so much documentation, written in
> | > a way that suggests arriving at the game at about halftime.
> | >
> | > anybody know about spf and what good it might be in a situation
> | > like mine? or is it something that would need to be done at the isp
> | > level?
> |
> | Do you have authoritative control over your DNS record(s)?  If not,
> | then SPF isn't for you.
> 
> a dandy question. do i? i'm on a plain vanilla cable modem connection. 
> i'm not even certain how i'd find out.

Simpleish. You must be running a DNS (e.g., bind) that will answer queries
for your domain. It is something that you must coordinate with your ISP. If
you have not actively set it up, then you are probably not authoritative.
Our ISP was reluctant to let us be authoritative. We had to beg.

Now, if you connect to your DNS with nslookup:

	nslookup - my.dns.com

and then type

	ls -t linux-sxs.org

Do you get a listing? Only the authoritative DNS should provide one. 
Otherwise you get an error message.The last parameter is the domain, not a
machine.

For those who use dig, I do not know the method. Maybe it is the same.



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