CentOS - Aug 2011 - using posfix on the local LAN, with internet FQDN

Hi all,

I hope someone can help me with this please.


One of our clients has an in-house Postfix mailserver which basically
downloads mail for the individual users from our mail server hosted on
the web using fetchmail.
They use our SMTP server to send mail. Their email clients are then
setup to get & send mail from the server, on 192.168.2.254 (for POP3 &
SMTP).  All mail between them on the local LAN gets send to each other
via the server, and not the internet.

This works quite well, but as soon as someone sends mail from the
Linux server directly (it has webmin + usermin installed and has a
basic webmail interface for when they're out of the office) it sends
mail using the local machine name, instead of the domain name.
for example, mail comes from esther at ser001.rewards.local.

How do I tell Postfix to automaticlly send mail from
<user>@<theirdomain.com> instead?


Sorry for asking this, but I don't know Postfix very well and don't
know what to call to, to search on google.

-- 
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532

> Hi all,
>
> I hope someone can help me with this please.
>
>
> One of our clients has an in-house Postfix mailserver which basically
> downloads mail for the individual users from our mail server hosted on
> the web using fetchmail.
> They use our SMTP server to send mail. Their email clients are then
> setup to get & send mail from the server, on 192.168.2.254 (for POP3
&
> SMTP).  All mail between them on the local LAN gets send to each other
> via the server, and not the internet.
>
> This works quite well, but as soon as someone sends mail from the
> Linux server directly (it has webmin + usermin installed and has a
> basic webmail interface for when they're out of the office) it sends
> mail using the local machine name, instead of the domain name.
> for example, mail comes from esther at ser001.rewards.local.
>
> How do I tell Postfix to automaticlly send mail from
> <user>@<theirdomain.com> instead?
>
I have this in main.cf:

myhostname = mail.braha.nl
myorigin = $mydomain

Think the second one is what you need.
>
> Sorry for asking this, but I don't know Postfix very well and don't
> know what to call to, to search on google.
>
> --
> Kind Regards
> Rudi Ahlers
> SoftDux
>
> Website: http://www.SoftDux.com
> Technical Blog: http://Blog.SoftDux.com
> Office: 087 805 9573
> Cell: 082 554 7532
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>

-- 
L. de Braal
BraHa Systems
NL - Terneuzen
T +31 115 649333
F +31 115 649444

Hi Rudy

On 18 August 2011 14:49, Rudi Ahlers <Rudi at softdux.com>
wrote:
> Hi all,
>
> I hope someone can help me with this please.
>
>
> One of our clients has an in-house Postfix mailserver which basically
> downloads mail for the individual users from our mail server hosted on
> the web using fetchmail.
> They use our SMTP server to send mail. Their email clients are then
> setup to get & send mail from the server, on 192.168.2.254 (for POP3
&
> SMTP). ?All mail between them on the local LAN gets send to each other
> via the server, and not the internet.
>
> This works quite well, but as soon as someone sends mail from the
> Linux server directly (it has webmin + usermin installed and has a
> basic webmail interface for when they're out of the office) it sends
> mail using the local machine name, instead of the domain name.
> for example, mail comes from esther at ser001.rewards.local.
>
> How do I tell Postfix to automaticlly send mail from
> <user>@<theirdomain.com> instead?
>
This comes straight out of the main.cf file and may be of some assistance:

# INTERNET HOST AND DOMAIN NAMES
#
# The myhostname parameter specifies the internet hostname of this
# mail system. The default is to use the fully-qualified domain name
# from gethostname(). $myhostname is used as a default value for many
# other configuration parameters.
#
#myhostname = host.domain.tld
#myhostname = virtual.domain.tld

# The mydomain parameter specifies the local internet domain name.
# The default is to use $myhostname minus the first component.
# $mydomain is used as a default value for many other configuration
# parameters.
#
#mydomain = domain.tld

# SENDING MAIL
#
# The myorigin parameter specifies the domain that locally-posted
# mail appears to come from. The default is to append $myhostname,
# which is fine for small sites.  If you run a domain with multiple
# machines, you should (1) change this to $mydomain and (2) set up
# a domain-wide alias database that aliases each user to
# user at that.users.mailhost.
#
# For the sake of consistency between sender and recipient addresses,
# myorigin also specifies the default domain name that is appended
# to recipient addresses that have no @domain part.
#
#myorigin = $myhostname
myorigin = $mydomain
#myorigin = $myhostname


>
> Sorry for asking this, but I don't know Postfix very well and don't
> know what to call to, to search on google.
>
> --
> Kind Regards
> Rudi Ahlers
> SoftDux
Regards,
  Andy.