But wait, there's more you also get ...
$ hostname; date --iso-8601=seconds; (for IP in 10.1.10.109
96.86.170.229 2001:470:1f04:19e::2 2001:470:1f05:19e::2
2001:470:1f05:19e::3 2001:470:1f05:19e::4 2001:470:1f05:19e::5
2001:470:1f05:19e::6 2001:470:1f05:19e::7 2001:470:1f05:19e::8
2001:470:1f05:19e::9 2001:470:1f05:19e::a
2603:3024:1b29:0:5054:ff:fe13:5199 2603:3024:1b29:2::2
2603:3024:1b29:2::3 2603:3024:1b29:2::4 2603:3024:1b29:2::5
2603:3024:1b29:2::6 2603:3024:1b29:2::7 2603:3024:1b29:2::8
2603:3024:1b29:2::9 2603:3024:1b29:2::a; do echo "$IP" $(dig
@ns1.google.com. -b "$IP" +short o-o.myaddr.l.google.com. TXT | tr -d
'"'); done)
balug-sf-lug-v2.balug.org
2026-03-01T22:28:53+00:00
10.1.10.109 96.86.170.230
96.86.170.229 96.86.170.229
2001:470:1f04:19e::2 2001:470:1f04:19e::2
2001:470:1f05:19e::2 2001:470:1f05:19e::2
2001:470:1f05:19e::3 2001:470:1f05:19e::3
2001:470:1f05:19e::4 2001:470:1f05:19e::4
2001:470:1f05:19e::5 2001:470:1f05:19e::5
2001:470:1f05:19e::6 2001:470:1f05:19e::6
2001:470:1f05:19e::7 2001:470:1f05:19e::7
2001:470:1f05:19e::8 2001:470:1f05:19e::8
2001:470:1f05:19e::9 2001:470:1f05:19e::9
2001:470:1f05:19e::a 2001:470:1f05:19e::a
2603:3024:1b29:0:5054:ff:fe13:5199 2603:3024:1b29:0:5054:ff:fe13:5199
2603:3024:1b29:2::2 2603:3024:1b29:2::2
2603:3024:1b29:2::3 2603:3024:1b29:2::3
2603:3024:1b29:2::4 2603:3024:1b29:2::4
2603:3024:1b29:2::5 2603:3024:1b29:2::5
2603:3024:1b29:2::6 2603:3024:1b29:2::6
2603:3024:1b29:2::7 2603:3024:1b29:2::7
2603:3024:1b29:2::8 2603:3024:1b29:2::8
2603:3024:1b29:2::9 2603:3024:1b29:2::9
2603:3024:1b29:2::a 2603:3024:1b29:2::a
$
See also / references:
https://lists.balug.org/mailman3/hyperkitty/list/balug-admin@lists.balug.or…
On Sat, Feb 28, 2026 at 6:29 PM Michael Paoli
<michael.paoli(a)berkeley.edu> wrote:
>
> So, on the BALUG VM (hosting balug.org, sf-lug.org & berkelug.com.
> (except list on those latter two), many additional domains, DNS
> primaries for all those, additional secondaries, etc.
>
> So, IP addresses:
> $ (for IP in 10.1.10.109 96.86.170.229 2001:470:1f04:19e::2
> 2001:470:1f05:19e::2 2001:470:1f05:19e::3 2001:470:1f05:19e::4
> 2001:470:1f05:19e::5 2001:470:1f05:19e::6 2001:470:1f05:19e::7
> 2001:470:1f05:19e::8 2001:470:1f05:19e::9 2001:470:1f05:19e::a
> 2603:3024:1b29:0:5054:ff:fe13:5199; do echo "$IP" $(dig
> @ns1.google.com. -b "$IP" +short o-o.myaddr.l.google.com. TXT | tr -d
> '"'); done)
> 10.1.10.109 96.86.170.230
> 96.86.170.229 96.86.170.229
> 2001:470:1f04:19e::2 2001:470:1f04:19e::2
> 2001:470:1f05:19e::2 2001:470:1f05:19e::2
> 2001:470:1f05:19e::3 2001:470:1f05:19e::3
> 2001:470:1f05:19e::4 2001:470:1f05:19e::4
> 2001:470:1f05:19e::5 2001:470:1f05:19e::5
> 2001:470:1f05:19e::6 2001:470:1f05:19e::6
> 2001:470:1f05:19e::7 2001:470:1f05:19e::7
> 2001:470:1f05:19e::8 2001:470:1f05:19e::8
> 2001:470:1f05:19e::9 2001:470:1f05:19e::9
> 2001:470:1f05:19e::a 2001:470:1f05:19e::a
> 2603:3024:1b29:0:5054:ff:fe13:5199 2603:3024:1b29:0:5054:ff:fe13:5199
> $ dig -4 @ns1.google.com. +short o-o.myaddr.l.google.com. TXT | tr -d '"'
> 96.86.170.229
> $ dig -6 @ns1.google.com. +short o-o.myaddr.l.google.com. TXT | tr -d '"'
> 2603:3024:1b29:0:5054:ff:fe13:5199
> $
> Recently started adding more. Some of the motivations:
> Had some recent minor glitches between Hurricane Electric (HE.net,
> tunnelbroker.net) IPv6 IPs and AT&T (att.com) IPv6 IPs.
> I've also got Comcast Business IPv6 IPs potentially available to me (my
> current ISP), but for the most part hadn't been using those. Longer
> term will likely move to AT&T, but in the meantime. So, started adding
> those, not yet all that significantly pressed into service, but mostly
> set. Just add relevant statics, DNS entries, etc., and good to go.
> And checking side-by-side, the HE.net/tunnelbroker.net IPs perform very
> surprisingly well - even with their tunneling, latency and number of
> hops, almost indistinguishable. And the up-front prep work will make later
> transitioning to AT&T IPs that much simpler.
>
> Also, changed the Mail Transport Agent (MTA) from exim4 to Postfix.
> There were multiple motivations on that, including:
> exim4 just wasn't cutting it anymore. Most notably, though exim4 has
> configuration for source IP(s) for SMTP send, it just doesn't work. I'd
> mostly kludged around that, by it / the routing generally using by
> default, source of the last (IPv4 or IPv6) IP address added, but that
> was no longer sufficient and had bitten me multiple times before.
> Though it's documented - it just plain doesn't work - and all the
> research basically pointed to same, and I certainly wasn't the only one
> to switch from exim4 to Postix to get a proper working solution.
> Additionally, exim4 has still no capabilities for per-domain aliasing.
> Very annoying, as that means if there's rsvp(a)balug.org, then the alias
> for that also applies to rsvp(a)lists.balug.org, and any other mail
> domains too - not at all what's desired. So, with Postfix, can well
> separate those out. Furthermore, part of the anti-spam configuration
> I'd been using with exim4 was highly outdated and not being maintained,
> and a bit fragile and crusty, so, also good to get away from that, and
> dropping exim4 was also a cleaner simpler way to do that. And, yet
> another advantage, mailman3 well supports two MTAs, Postfix and exim,
> but it better supports and default configurations support Postix, so,
> even simpler to deal with mailman3 on Postfix than exim4. So, all
> those reasons, quite overdue to switch to Postfix, and have now done
> so. And well tested on the BALUG-Test list too. Most all changes were
> also first tested on a test VM (balug13) too, before being implemented
> on the production VM (balug).
>
> In the bit of example testing further above, can see for each of many
> source IPs, that for all of them we can see that they not only route
> properly, but the server in fact sees the expected source IP address,
> (same IP, excepting the one v4 behind NAT/SNAT) and likewise also with
> default source for v4 and v6 - though on the latter I may or may not
> want to change what that default is. But with MTA and DNS using their
> proper source IP addresses for their services, in those case, doesn't
> much matter what the defaults are when the sources are set properly
> when used for the services, most notably source IP on MTA when it sends
> or attempts to send email.
>
> So, fair bit of cleanup and improvements on that infrastructure, and
> helps well clear the way for more.
Good to know about the flurry of recent test status updates.
-A
> When replying, please edit your Subject line so it is more specific
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> Today's Topics:
>
> 1. test - ignore (after bit of network config rollback - which itself
> was fine, but exim4 again had source IP issues)
> (Michael Paoli)
> 2. test - ignore (list) - after exim4 package upgrades
> (test-dllsepcqvxv2vr5idrgh(a)balug.org)
> 3. test - ignore (after adding back full network and exim4 --> postfix)
> (Michael Paoli)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Sat, 28 Feb 2026 09:15:11 -0800
> From: Michael Paoli <michael.paoli(a)berkeley.edu>
> Subject: [BALUG-Test] test - ignore (after bit of network config
> rollback - which itself was fine, but exim4 again had source IP
> issues)
> To: BALUG-test <balug-test(a)lists.balug.org>
> Message-ID:
> <CAPU_E+dkV-7fvtasPBtAqrOGpzk+=m0C7r=GkQUdp2oE5v-V5Q(a)mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> test - ignore (after bit of network config rollback - which itself was
> fine, but exim4 again had source IP issues)
>
> ------------------------------
>
> Message: 2
> Date: Sun, 01 Mar 2026 00:04:40 +0000
> From: <test-dllsepcqvxv2vr5idrgh(a)balug.org>
> Subject: [BALUG-Test] test - ignore (list) - after exim4 package
> upgrades
> To: <balug-test(a)lists.balug.org>
> Cc: test-dllsepcqvxv2vr5idrgh(a)balug.org
> Message-ID: <1772323480.HGu+oxB7q7B+s6ru(a)balug-sf-lug-v2.balug.org>
>
> test body - ignore 2026-03-01T00:04:40Z 1772323480
>
>
> ------------------------------
>
> Message: 3
> Date: Sat, 28 Feb 2026 16:22:17 -0800
> From: Michael Paoli <michael.paoli(a)berkeley.edu>
> Subject: [BALUG-Test] test - ignore (after adding back full network
> and exim4 --> postfix)
> To: BALUG-test <balug-test(a)lists.balug.org>
> Message-ID:
> <CAPU_E+d4LNcrd0246wwgUNJtzc7Qos-D=CSNMh+V-kiEm0UN9g(a)mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> test - ignore (after adding back full network and exim4 --> postfix)
>
> ------------------------------
>
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