On Mon, 23 Jun 2003, Adrian Golumbovici wrote:

> Hi all,
> 
> I just installed/configured/secured my own postfix server with a dyndns address. My 
> dyndns entry is as MX server registered and it is working. I normally have about 
> maximum 5 minutes offline time. My provider disconnects me each 24 hours, but linux 
> PC connects again immediately and updates dyndns entry, which normally takes about 
> maximum 5 minutes to propagate). In this time the dyndns still points to the old ip 
> address, which is either not connected (no user got it in so short time) or points 
> to someone who doesn't have the ports opened (no email server). I wondered what 
> happens if someone/some-server tries to deliver me email in this time. Will it be 
> bounced or will it retry and finally send it to me when connection available again?
> 
> Best regards,
> Adrian

Failing to connect to the old IP isn't really a concern, since (as previously
mentioned) the sending server will retry.  Of more concern is the fact
that someone could take advantage of your situation and maliciously
configure a mailserver to accept mail as your domain.  If they manage to
grab your most recent IP through war-dialing (of sorts) and your old IP is still
cached on name servers that are being used to look-up your MX record,
then they can hijack your incoming e-mail.

If your e-mail means much to you I would highly suggest paying the extra
$10/month for a static IP, or trying to find an ISP who provisions
static IPs.

-- 
-chort
AKA Brian Keefer
The thoughts I express are generally piped from /dev/random,
needless to say they do not represent my fine employer:
CipherTrust, Inc - www.ciphertrust.com

Want to buy your Pack or Services from MandrakeSoft? 
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