On Fri, Jun 21, 2013 at 04:48:22AM +0600, Denis Fateyev wrote: > > Hello there, > Is there an option to select MX type order for outgoing messages (IPv4 > first, then IPv6, or vice versa), and/or entirely disable IPvX usage > for outgoing sessions? > For example, I have a bunch of machines that don't have IPv6 support, > so while sending mails to @[1]gmail.com 'smtp-out' always starts from > IPv6 MX which produces only faulty connection attempts and wastes time. > I haven't found an option in program to force IPv4 using. > More general: is there an option in global scope which controls allowed > protocols?
I can think of two ways to do that at the moment. One way is to add "family inet4" to your resolv.conf. I think it is only officially supported on OpenBSD, but smtpd will handle it fine, whatever system you run. A drawback is that it is a global setting, but if you don't have ipv6 on those machines it should be fine. Of course, the biggest problem is that you need a resolver option that might not be available on your system, which is maybe not desirable, from an admin point of view. An other way is to add an explicit source address (or table) on your relay rules: "accept for any relay source aaa.bbb.ccc.ddd". This way smtpd will only attempt to connect to host on their v4 address. The problem is that you have to hard-code your IP in the config file. It might be acceptable though, at least as a temporary workaround. I would say use the first option on OpenBSD. Otherwise either ignore the failures, or use the second option for now. Eric. -- You received this email because you are subscribed to mailing list: [email protected] To unsubscribe, send mail with subject: [[email protected]] unregister
