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Re: Question about the draft

2004-10-14 09:54:56

On Oct 14, 2004, at 8:31 AM, guy wrote:

In sections: B.1 Simple Examples

Please explain why this is true:
        -- sending host 10.0.0.4 fails (reverse IP is not valid)

Is it because the IP address is an RFC-1918 address?
No.  It fails because first the PTR record is looked up:

$ORIGIN 0.0.10.in-addr.arpa.
4           PTR bob.example.com.

Then bob.example.com's A record is looked up:

$ORIGIN example.com.
bob         A   192.0.2.66

Since 192.0.2.66 != 10.0.0.4, there is no validated domain name for 10.0.0.4. Therefore, there is no validated domain name that is within example.com. And so, the "ptr" directive doesn't match. The next directive is "-all", which does match, and the IP fails the test.

        - Mark