Exim refuses IPv6 connections

P

Panormitis

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When doing a "telnet localhost 25" Exim accepts connections just fine.
However, when doing "telnet localhost6 25" or "telnet ::1 25" I get a "Connection Refused" error.
It seems Exim listens to ports 25, 587 & 465, but only for IPv4 addresses.

The ports are open in ip6tables and Exim is compiled with IPv6 support (verified by "exim -bV | grep Support"), but Exim refuses IPv6 connections.

Any ideas?
Should I change something in exim.conf to allow IPv6 connections?
In case it matters, it's a CentOS 6 system.
 
Check if you have in /etc/exim.conf this line:

disable_ipv6=true

If yes, set it to false.

If this didnt help, please provide your exim.conf version (and also consider to update it to latest from CB)

Regards
 
SeLLeRoNe, I haven't set disable_ipv6=true in exim.conf (this was one of the things I checked too).
But your advise got me wondering what would happen if I set it as disable_ipv6=false.
Then Exim complained: disable_ipv6 option set for the second time.
So I did a grep -r "disable_ipv6" /etc and it appears disable_ipv6=true is set in /etc/exim.variables.conf.
I changed it and I added disable_ipv6=false to /etc/exim.variables.conf.custom.
Exim accepts IPv6 connections now. Thanks for the advice.

Peter thanks for the warning, I'll check about SPF.
I was thinking to create a script to add the IPv6 address to the SPF record automatically, when a domain/account is created.
 
Petertjuh360 said:
See http://www.directadmin.com/features.php?id=1549
Click to expand...

Thanks for the link.
However I have set Exim to send e-mails from the user's IP address, so I would prefer something like: |DOMAIN|.="v=spf1 a mx ip4:|IP4| ip6:|IP6| ~all"
Where |IP4| & |IP6| would be substituted with the user's IPs, but unfortunately something like that is not supported by DirectAdmin.

In my opinion, it would be a nice feature to have.
For now, I might be able to create a shell script, to manipulate the SPF record accordingly.
 
I'm testing Exim with IPv6 and so far I found out the following:

The ifcfg-ethX file must have "IPV6_AUTOCONF=no" to prevent the network interface from getting link-local addresses, because Exim tends to use it as an outgoing address.

If an e-mail is sent to a GMail address, it would be rejected because the IPv6 address is not included in the SPF record.
Since Exim is configured to send e-mails from each user's IP, I had to either and the appropriate IPv6 address to the SPF record of each domain/user or just add a range of addresses on all SPF records.
So I decided to add to directadmin.conf something like "extra_spf_value= ip6:1234:1234:1234:58::1/112", and edited the SPF records of the zone files.
Well, it's not a very elegant solution (each SPF record now allows an IPv6 address range from 1234:1234:1234:58::1 to 1234:1234:1234:58::ffff and not just one address), but it works.
Google is happy now and accepts the SPF.

However when Exim contacts Google's server to send e-mail, it doesn't use the IPv6 address of the domain or the default IPv6 address of the server.
It uses the last IPv6 address configured on the ifcfg-ethX interface.
This looks strange to me, perhaps it's a bug.
How could I prevent this behavior and make Exim use the appropriate IPv6 address of the user to send e-mail?
Any ideas?
 
Panormitis said:
It uses the last IPv6 address configured on the ifcfg-ethX interface.
This looks strange to me, perhaps it's a bug.
How could I prevent this behavior and make Exim use the appropriate IPv6 address of the user to send e-mail?
Any ideas?
Click to expand...

Hello,

Yes, that's true. And you can see an output of ifconfig and that IPv6 addresses are not sorted the traditional way. It was already discussed here a number of times, and still I have not found a solution for this. Unless to configure exim to choose IPv6 on a specified criteria.
 
Sorry for the bump but i have the same problem. Did you find a solution?

Emails are send with the default IPv6 address, not the address of the user.
 
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