nuc: note why its mail path differs from ks2/ks4 (source address, not config)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-08-28 17:44:03 +02:00
parent 6461bf7081
commit 6ab143c856
1 changed files with 8 additions and 0 deletions
@@ -82,6 +82,14 @@ zed → mail (bsd-mailx) → /usr/sbin/sendmail = msmtp → mail.lutran.fr:587 (
  `zed.rc.orig`. **No credentials in this file** — they live only in
  `/etc/msmtprc`.
 **Why nuc differs from ks2/ks4** (which mail via s-nail straight to
 port 25, and work fine): it is not the zed config, it is the source
 address. ks4 *is* the mail server's host (internal client,
 `mynetworks`); ks2 is a datacenter IP with a PTR. nuc sends from a
 **dynamic home IP with no PTR and no SPF alignment**, so the inbound
 MX path treats it like any stranger. Hence submission + auth here,
 deliberately different from the other two hosts.
 Two dead ends worth remembering:
 - **Port 25 is the wrong port for alerts.** Authentication succeeds,