How-to use external smtp server ?

[mikeb]

Hi all,
My ISP is blocking port 25 and I cannot use my own smtp server, it needs to be redirecting all outgoing emails towards my isp smtp server.

Thank you

[joximu]

Have a look in the postfix documentation...

eg. http://www.postfix.org/BASIC_CONFIGURATI...#relayhost

[BeNe]

Or in the Wiki --> http://www.isp-control.net/documentation...mtp_server

Greez BeNe

[momo]

This works for a home laptop I use for monitoring.
It sends db backup reports and nagios alerts.
I haven't test for virtual mail.

Code:

nano /etc/postfix/main.cf
myhostname = my-isp.tld
mydomain = $myhostname
myorigin  = $myhostname
mydestination = $myhostname
relayhost = smtp.my-isp.tld

/etc/init.d/postfix restart

[puster]

Hi everybody,

is there a chance that this can be done per domain, or is this a setting which
generally only applies to an entire server?

[momo]

I doubt.

http://www.postfix.org/postconf.5.html
Search for multiple SMTP

[kilburn]

Setting otugoing mail relays for specific domains *can* be done, but it involves a great deal of postfix's custom configuration, and I'm not sure about how well this will play with ispcp's settings.

Nevertheless, what you need to do is add a new directive "sender_dependent_relayhost_maps = /etc/postfix/sender_dependent_relay". Thereafter, create the referenced file and write there something like "@domain.tld smtp:[your.provider.smtp.host]" (brackets must be there). Postmap this file and restart postfix.

By doing this, postfix will use "your.provider.smtp.host" as an outgoing relay whenever mails come from "xxxx@domain.tld" users. Additionally, you will probably also have to add these directives to main.cf:

Code:

smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd

And write the user/password combination to identify against your isp's smtp server in the "/etc/postfix/sasl_passwd" file (that must also be postmapped). It should contain something like:

Code:

[your.provider.smtp.host]    user:password

Restart postfix and it will identify as this user whenever relaying mails through your isp's smtp server.

[edinn]

is it possible to make manual entry in postfix transport map, per domain, such as :
/etc/postfix/ispcp/transport:
domain.tld smtp:mx.google.com

(postmap that file and postfix reload after)

And ofc. to remove it from /etc/postfix/ispcp/domains

I tried that today, because mx entry was overwritten by dns template after subdomain addition, but gives me relay acc. denied.

[kilburn]

@edinn: what you're doing is completely different. Namely, you are choosing the next hop transport for a given destination domain. Contrastingly, in this thread we were discussing different outgoing relays based on source address (the sender domain).

[edinn]

k, tnx, I'll start a new topic