mail servers, dyndns, and mail forwarding

My ISP only gives me a dynamic IP address. I have a dyndns.org free
account which gives me a FQDN for whatever IP address I have, kept up to
date with a client program that checks the IP and updates dyndns.org's
DNS servers if necessary.

I have set up a postfix server on it, and can send mail direct to it.
However my "real" email address[es] are forwarded to my ISP assigned
email address via a free parking service.

I'd like to know if I set the free parking forwarding to my dyndns.org
address, will it continue to work after the IP address changes the next
time? ie, with these free parking utilities, are they based on the
names or IP addresses? When setting it up you type in a name, but does
that get resolved to an address at the other end and therefore assumed
static?

--
Troy Piggins : "My karma just ran over my dogma"
,-o
o ) Ubuntu linux 6.06 http://ubuntu.com RLU#415538 http://counter.li.org
`-o uptime: 08:45:10 up 1 day,10:10,2 users,load average:0.00,0.00,0.00

Re: mail servers, dyndns, and mail forwarding

On Fri, 30 Jun 2006, Troy Piggins wrote:

TP> My ISP only gives me a dynamic IP address. I have a dyndns.org free
TP> account which gives me a FQDN for whatever IP address I have, kept up to
TP> date with a client program that checks the IP and updates dyndns.org's
TP> DNS servers if necessary.
TP>
TP> I have set up a postfix server on it, and can send mail direct to it.
TP> However my "real" email address[es] are forwarded to my ISP assigned
TP> email address via a free parking service.
TP>
TP> I'd like to know if I set the free parking forwarding to my dyndns.org
TP> address, will it continue to work after the IP address changes the next
TP> time? ie, with these free parking utilities, are they based on the
TP> names or IP addresses? When setting it up you type in a name, but does
TP> that get resolved to an address at the other end and therefore assumed
TP> static?
TP>

If you are having mail delivered or forwarded to you home computer then it
must be online all the time otherwise the mail will bounce as it will have
nowhere to go to. So an ip change is not much of an issue as it won't
change very often. However, with the pc online all the time, you don't
need the domain parking tier to forward mail, you need a dns mx record
which points to a host name. dyndsn.org should be able to do that if they
are running dns for you or, if not, have a look at running your dns at
somewhere like http://xname.org/dynamic-update.php?language=en

One thing that may be a problem is sending mail from your mailserver using
a dynamic ip address: doesn't half the world have a policy of rejecting
mail from a dynamic addresses? Does your isp provide a smart host that
will get around this problem?

--
Alan

( If replying by mail, please note that all "sardines" are canned.
There is also a password autoresponder but, unless this a very
old message, a "tuna" will swim right through. )

Re: mail servers, dyndns, and mail forwarding

* Alan Clifford wrote:
> On Fri, 30 Jun 2006, Troy Piggins wrote:
>
> TP> My ISP only gives me a dynamic IP address. I have a dyndns.org free
> TP> account which gives me a FQDN for whatever IP address I have, kept up to
> TP> date with a client program that checks the IP and updates dyndns.org's
> TP> DNS servers if necessary.
> TP>
> TP> I have set up a postfix server on it, and can send mail direct to it.
> TP> However my "real" email address[es] are forwarded to my ISP assigned
> TP> email address via a free parking service.
> TP>
> TP> I'd like to know if I set the free parking forwarding to my dyndns.org
> TP> address, will it continue to work after the IP address changes the next
> TP> time? ie, with these free parking utilities, are they based on the
> TP> names or IP addresses? When setting it up you type in a name, but does
> TP> that get resolved to an address at the other end and therefore assumed
> TP> static?
> TP>
>
> If you are having mail delivered or forwarded to you home computer then it
> must be online all the time otherwise the mail will bounce as it will have
> nowhere to go to. So an ip change is not much of an issue as it won't
> change very often. However, with the pc online all the time, you don't
> need the domain parking tier to forward mail, you need a dns mx record
> which points to a host name. dyndsn.org should be able to do that if they
> are running dns for you or, if not, have a look at running your dns at
> somewhere like http://xname.org/dynamic-update.php?language=en

I'll look into that, thanks.

> One thing that may be a problem is sending mail from your mailserver using
> a dynamic ip address: doesn't half the world have a policy of rejecting
> mail from a dynamic addresses? Does your isp provide a smart host that
> will get around this problem?

Yes, my ISP has a smart host which I use.
In terms of whether my mail gets blocked - haven't had any problems
lately. Or is that why noone mails me anymore.... just kidding.

--
Troy Piggins : "My karma just ran over my dogma"
,-o
o ) Ubuntu linux 6.06 http://ubuntu.com RLU#415538 http://counter.li.org
`-o uptime: 11:05:07 up 2 days,12:30,2 users,load average:0.00,0.00,0.00