Postfix for sending mails through DSL router
Markus R.
I'm new to Postfix / Sendmail, and, perhaps someone has done a similar
task yet:
I have a small home network with 4 linux servers and some windows
machines. All machines are connected via 10/100 switch and can access the
internet via ADSL router (IP masquerading, dynamic IP from internet side).
Now I'd like to send emails not only into the same subnet but also into
the internet to public email servers for getting notified wherever I am
at the moment.
Also worth to mention is that there's no need to receive emails via this
machine because I use to get emails via webmail / browser from an
external ISP.
As an MTA I already installed Postfix 2.5.6 on top of Mandriva linux
2009.1. To not having to rewrite my scripts which rely on sendmail, I use
the sendmail.postfix compatibility layer.
Well, sending emails within the home network works but any attempt to
send emails to accounts outside of this network lead to
"553 sorry, your envelope sender domain must exist".
In the wireshark trace I see that a connection to the foreign MTA is
established but obviously without success. - May this error arise from
the fact that this machine cannot be "seen" from outside, i.e. it has no
public IP address?
Well, as a part of a home network it also does not have a "fully
qualified", registered domain name, it just has a hostname and a static
internal IP.
Any idea what could be wrong here?
Thanks in advance,
best regards,
Markus
--
Please reply to group only.
For private email please use http://www.dipl-ing-kessler.de/email.htm
Res
> Well, as a part of a home network it also does not have a "fully
> qualified", registered domain name, it just has a hostname and a static
> internal IP.
>
> Any idea what could be wrong here?
Sure, you are asking a postfix question in a sendmail newsgroup.
Postfix has a very active mailing list, but if they answer you depends on
if they are a troll or someone with a bit of a clue, dont email weitse
directly even with a bug because he'll tell you to mail to the list,
then ignore it there as well :)
hes about as up himself as DJB.
--
Res
"What does Windows have that Linux doesn't?" - One hell of a lot of bugs!
Markus R.
> On Mon, 27 Dec 2009, Markus R. Keßler wrote:
>
>> Well, as a part of a home network it also does not have a "fully
>> qualified", registered domain name, it just has a hostname and a static
>> internal IP.
>>
>> Any idea what could be wrong here?
>
> Sure, you are asking a postfix question in a sendmail newsgroup.
As far as concerning the above, sendmail and postfix seem to behave
similar. Moreover, on many servers I had been working on there's even
qmail symlinked and sometimes it had been *RENAMED* to "sendmail".
As far as I have seen this does its job.
> Postfix has a very active mailing list, but if they answer you depends
> on if they are a troll or someone with a bit of a clue, dont email
> weitse directly even with a bug because he'll tell you to mail to the
Don't bother about - I don't intend to email him directly.
Well, I know that it was possible to only *SEND* emails out, because
there are articles about that item, but I'm not sure if there's a problem
with the rpm package provided with the distribution. - As I've said I'm
new to configuring postfix with or without "postfix to sendmail
compatibility module".
So I'll be glad about any hints.
Best regards,
Burkhard Ott
> 553 sorry, your
> envelope sender domain must exist".
Do you have a valid domain you're sending from?
Are you sending through a smartrelay?
cheers?
J.O. Aho
> Am Mon, 28 Dec 2009 09:43:51 +1000 schrieb Res:
>
>> On Mon, 27 Dec 2009, Markus R. Keßler wrote:
>>
>>> Well, as a part of a home network it also does not have a "fully
>>> qualified", registered domain name, it just has a hostname and a static
>>> internal IP.
>>>
>>> Any idea what could be wrong here?
>> Sure, you are asking a postfix question in a sendmail newsgroup.
>
> As far as concerning the above, sendmail and postfix seem to behave
> similar. Moreover, on many servers I had been working on there's even
> qmail symlinked and sometimes it had been *RENAMED* to "sendmail".
> As far as I have seen this does its job.
Thats for there are applications which directly uses sendmail to send mail, if
then install one of the "newer" MTAs, then those applications would stop
working, this why the other MTAs do include a "sendmail" binary/symlink, but
it has nothing to do with sendmail itself, questions regarding the
binary/symlink are to be asked at a forum/newsgroup/irc channel dedicated to
the MTA you use, not here (if not the rela sendmail installed).
--
//Aho
Ingo Strohm
wenn sich 2 Deutsche englisch posten :)
Bei mir hatte das etwas mit SMTP relaying restrictions zu tun.
Ich hatte mir tagelang die "Z�hne ausgebissen" :(
Gru� Ingo
Burkhard Ott wrote:
Markus R.
Hi, thanks,
well, no, there's no fully qualified, i.e., registered domain name for
that box. If this is what you mean. This box is just behind a DSL router
and is *NOT* visible on the internet due to masquerading.
Also, the public IP of the router changes every few hours.
So, from the beginning I doubted that this would work this easy - that
was one of the reasons for asking here.
What's puzzling me is, that this guy seems to have a similar network
configuration and he claimed that it would work:
http://forums.fedoraforum.org/archive/index.php/t-82466.html
B.t.w., I have several domain names registered at denic, for instance
"dipl-ing-kessler.de", which is hosted by a hoster called "fritsch
hosting", but the contents hosted on these machines have nothing to do
with this experiment made on my own network.
But, in my understanding, these domains cannot be assigned to the
internal MTA by modifying one of the mx records, right?
Do I have to get a fixed IP and a unique domain name to get sendmail /
postfix work as a standalone MTA on my own box?
Or, can DynDNS be used here?
Thanks,
Res
>> Am Sun, 27 Dec 2009 17:50:45 +0000 schrieb "Markus R." Keßler:
>>
>>> 553 sorry, your
>>> envelope sender domain must exist".
>>
> well, no, there's no fully qualified, i.e., registered domain name for
> that box. If this is what you mean. This box is just behind a DSL router
I was going to continue to ignore this thread since you are using postfix
and the sendmail you have issue with, is a postfix "sendmail" as in
sending-your-mail binary, but... your issue is clear as that message is.
> and is *NOT* visible on the Internet due to masquerading.
> Also, the public IP of the router changes every few hours.
There are two requirements for sending mail to most Internet hosts
1/ your envelope sender must exist, in other words don't try send mail as
dsfg...@fghfgd.org because it will fail, if you have some sort of domain
name, set it up on your box, then, ensure you have reverse DNS entries for
your IP, and that that rDNS entry also resolves to your A record, now, you
need a valid address so you can get return email.
It wont really work in your case because you said your hostmark changes
every few hours (strange unless on dialup), but there is no reason you
couldn't use the temp assigned hostname given to you by your ISP, even if
its cp2-123-blah.dsl.yourisp.com as that is a valid hostname, but ...
> B.t.w., I have several domain names registered at denic, for instance
> "dipl-ing-kessler.de", which is hosted by a hoster called "fritsch
So you could create a hostname under this domain and use that, EG,
markus.dipl-ing-kessler.de and then set up your mail server as that
hostname, setup your mail clients to use it as well, then it should work,
and yes dyndns service would be needed, if you want to get email back at
that address.
> Do I have to get a fixed IP and a unique domain name to get sendmail /
static IP is best for mail servers, as many ISP's and companies etc block
on dynamic users stopping you from sending them mail, some blockings exist
for short hostname TTL's, which dyndns services must be given your IP can
change at any time, some block on hostnames with IP's in them, as they
would ordinarily not be classed as a mail server.
Burkhard Ott
> Ist schon lustig,
>
> wenn sich 2 Deutsche englisch posten :)
>
> Bei mir hatte das etwas mit SMTP relaying restrictions zu tun.
>
> Ich hatte mir tagelang die "Zähne ausgebissen" :(
>
> Gruß Ingo
>
>
> Burkhard Ott wrote:
>> Am Sun, 27 Dec 2009 17:50:45 +0000 schrieb "Markus R." Keßler:
>>
>>> 553 sorry, your
>>> envelope sender domain must exist".
>>
>> Do you have a valid domain you're sending from? Are you sending through
>> a smartrelay?
>>
>> cheers?
Yep, but the group is english :-).
Burkhard Ott
> well, no, there's no fully qualified, i.e., registered domain name for
> that box. If this is what you mean. This box is just behind a DSL router
> and is *NOT* visible on the internet due to masquerading. Also, the
> public IP of the router changes every few hours.
Doesn't matter at all, you just need that if you wanna receive emails.
In your case use your IPS's smartrelay (option is called relayhost).
Sending directly makes no sense in your case, since you get more bounces
than sucessfull delivered emails.
Most MTA check if you're densing with an valid domain from a valid
address.
e.g. if I send with your domain from my IP a couple MTA's will check if
the DNS entry fits to the IP, if not I can't send that email.
There are a couple other checks too, like RBL etc.
So sending through your ISP's smartrelay is one of the options you should
keep in mind.
Or setup a valid MTA in public pace and use this machine.
> So, from the beginning I doubted that this would work this easy - that
> was one of the reasons for asking here.
Oh, it is easy there are only a couple things you should take care.
> What's puzzling me is, that this guy seems to have a similar network
> configuration and he claimed that it would work:
>
> http://forums.fedoraforum.org/archive/index.php/t-82466.html
Yeah but his mail gets rejected on its own server, as far as I have seen
you can send through your MTA but the recipient MTA reject your mail ince
you're either using a non valid domain or your IP has no valid domain
name.
>
> B.t.w., I have several domain names registered at denic, for instance
> "dipl-ing-kessler.de", which is hosted by a hoster called "fritsch
> hosting", but the contents hosted on these machines have nothing to do
> with this experiment made on my own network. But, in my understanding,
> these domains cannot be assigned to the internal MTA by modifying one of
> the mx records, right?
No you don't need that.
> Do I have to get a fixed IP and a unique domain name to get sendmail /
> postfix work as a standalone MTA on my own box? Or, can DynDNS be used
> here?
You can use dyn DNS, but much more comfy in terms of error management/
detection is a smarthost.
cheers
Burkhard Ott
> Bei mir hatte das etwas mit SMTP relaying restrictions zu tun.
>>> 553 sorry, your
>>> envelope sender domain must exist".
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If the remote MTA sends you this error?
Sounds weird.
cheers
Burkhard Ott
> Bei mir hatte das etwas mit SMTP relaying restrictions zu tun.
>>> 553 sorry, your
>>> envelope sender domain must exist".