Wietse Venema wrote, On 21-07-09 23:12:
Joris Dobbelsteen:
[ Charset ISO-8859-1 unsupported, converting... ]
I'm using Postfix 2.3 (with debian etch, but I'm planning to go to
postfix 2.5 with debian lenny). I'm using the postfix box solely for
relaying e-mail and doing virus/spam scanning. Mail for local domains is
relayed to a local server and everything else goes to my ISPs server. I
currently use transport_maps to manage this and that is working fine for
a couple years.
Now I want to reduce the use of my ISP mail server. For IPv4 this is not
possible: its troublesome with residential access & my ISP blocks
outgoing port 25. However I have an IPv6 ip address where mail delivery
is available.
Is there any possibility to use the "transport_maps" to indicate
multiple destinations?
No, but perhaps it is enough to set smtp_fallback_relay to the ISP.
smtp_fallback_relay = [mail.isp.example]
Wietse
I thought so. Thanks for the confirmation, suggestion and fast reply.
However that option is scaring me due to mailing loops. Postfix is
behind NAT on a residential ADSL connection, meaning it doesn't know its
Internet IP address (for certain). Besides the 'internal' hostname
doesn't necessarily reflect the outside one.
This is because "internal" is also a relay destination and I simply
cannot guarantee it's ready to receive email.
====
A better idea seems to be looking a bit deeper into master.cf and see if
I can add some entry here that does what I want. Currently it is:
---
familiedobbelsteen.nl smtp:joris2k.local
* smtp:[smtp.online.nl]
---
Of course there is already the existing "relay" entry here, so:
---
familiedobbelsteen.nl relay:joris2k.local
* smtp:[smtp.online.nl]
---
smtp unix - - - - - smtp
# When relaying mail as backup MX, disable fallback_relay to avoid MX loops
relay unix - - - - - smtp
-o fallback_relay=
-o smtp_fallback_relay=
# -o smtp_helo_timeout=5 -o smtp_connect_timeout=5
---
That should allow setting smtp_fallback_relay without interfering with
the other deliveries, right? It means I should be able to configure
smtp_fallback_relay somewhere else without any issues.
What makes me think about extending master.cf with a IPv6 direct
delivery service type, such that I add:
---
familiedobbelsteen.nl relay:joris2k.local
* direct6:
---
direct6 unix - - - - - smtp
-o inet_protocol=ipv6
-o smtp_fallback_relay=smtp:[smtp.online.nl]
---
This should work right, as I intend it? Or am I mistaken somewhere?
(Love mailing lists for organising my thoughts...)
Thanks,
- Joris
