[BALUG-Test] And now IPv4 email/SMTP/lists should be originating from the new IPv4 IP

[Michael Paoli]

Okay, this time, "for real"?

Yet another test.
With new ISP making IPv6 available, host had automagically picked
that up ... but alas, sending SMTP (& notably SPF) not prepared
for that ... and in any case wanted to test the IPv4, not IPv6 (oops),
so ... have autoconf & accept_ra disabled for now on that interface,
to be able to test via the new IPv4.

$ grep . /proc/sys/net/ipv6/conf/eth0/accept_ra  
/proc/sys/net/ipv6/conf/eth0/autoconf
/proc/sys/net/ipv6/conf/eth0/accept_ra:0
/proc/sys/net/ipv6/conf/eth0/autoconf:0
$ tail -n 6 /etc/sysctl.conf# for now, disable autoconf and accept_ra  
for IPv6 on eth0
# (not yet expected for SMTP SPF, etc.)
# grep . /proc/sys/net/ipv6/conf/eth0/accept_ra  
/proc/sys/net/ipv6/conf/eth0/autoconf
net.ipv6.conf.eth0.accept_ra=0
net.ipv6.conf.eth0.autoconf=0
########################################################################
$

> From: "Michael Paoli" <Michael.Paoli@cal.berkeley.edu>
> Subject: Re: [BALUG-Test] And now IPv4 email/SMTP/lists should  
> be	originating from the new	IPv4 IP
> Date: Tue, 17 Dec 2019 03:00:24 -0800

> And yet another test ... ought be a "good" one this time.  ;-)
> I *temporarily* disabled the IPv6 IPs - to force IPv4 (yes, there
> are other ways ... but for the relatively quick-and dirty ...
> also still testing and flushing out any minor issues that may
> remain in the full
> /etc/network/interfaces ifup/ifdown functionality).
>
> Also, relevant SPF records updated (alas, had dropped TTLs, and queued
> the changes, but forgot to get 'em in earlier) ... so that part
> of it ought work now too (and might otherwise prevent delivery,
> and rightfully so - especially with -all).
>
>> From: "Michael Paoli" <Michael.Paoli@cal.berkeley.edu>
>> Subject: Re: [BALUG-Test] And now IPv4 email/SMTP/lists should  
>> be	originating from the new	IPv4 IP
>> Date: Sun, 15 Dec 2019 07:44:52 -0800
>
>> Drats ... didn't actually go via IPv6 ... will test more later.
>>
>>> From: "Michael Paoli" <Michael.Paoli@cal.berkeley.edu>
>>> Subject: Re: [BALUG-Test] And now IPv4 email/SMTP/lists should  
>>> be	originating from the new	IPv4 IP
>>> Date: Sun, 15 Dec 2019 07:37:05 -0800
>>
>>> And one more test, with IPv6 temporarily disabled, to force IPv4 ...
>>>
>>>> From: "Michael Paoli" <Michael.Paoli@cal.berkeley.edu>
>>>> Subject: [BALUG-Test] And now IPv4 email/SMTP/lists should be  
>>>> originating from the new	IPv4 IP
>>>> Date: Sun, 15 Dec 2019 07:11:33 -0800
>>>
>>>> And now IPv4 email/SMTP/lists should be originating from the new IPv4 IP,
>>>> traffic may be via IPv4 or IPv6 (no change on the IPv6), but at least
>>>> for that traffic going over IPv4 ...