On 19/11/2025 11:13, Mike Scott wrote:

On 19/11/2025 10:33, The Natural Philosopher wrote:

# dig vps.templar.co.uk

dig -t any .......

essentially the same result, but thanks anyway...

--
Renewable energy: Expensive solutions that don't work to a problem that doesn't exist instituted by self legalising protection rackets that
don't protect, masquerading as public servants who don't serve the public.



--- PyGate Linux v1.5
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On 19/11/2025 18:03, Richard Kettlewell wrote:

The Natural Philosopher <tnp@invalid.invalid> writes:

So no, I don't know what it is now using as a DNS client.

Its very odd. I just did this...

# dig vps.templar.co.uk

; <<>> DiG 9.16.50-Raspbian <<>> vps.templar.co.uk
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24512
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 7f7ca1b95493f5c601000000691d9a18750f0123b174788b (good)
;; QUESTION SECTION:
;vps.templar.co.uk. IN A

;; ANSWER SECTION:
vps.templar.co.uk. 3726 IN A 185.113.128.151

;; Query time: 9 msec
;; SERVER: 192.168.0.101#53(192.168.0.101)
;; WHEN: Wed Nov 19 10:21:12 GMT 2025
;; MSG SIZE rcvd: 90
...then this...
root@heating-controller:/var/ramlog# echo "This is more bollox isn't
it?" | mail -a "From: oil-monitor@heating-controller" -s "another
message" superroot@templar.co.uk
...and this...
root@heating-controller:/var/ramlog# mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
C459D1FE2E 387 Wed Nov 19 10:21:48 oil-monitor@heating-controller
(Host or domain name not found. Name service error for
name=vps.templar.co.uk type=MX: Host not found, try again)
superroot@templar.co.uk

-- 0 Kbytes in 1 Request.

Now unless dig is using some other means than postfix to look up DNS,
it looks like the problem is in postfix somehow.

Maybe, but the above doesn?t prove it; you?ve asked for an A record but Postfix asks for an MX record, so your lookup won?t have populated the
cache (if there is one). (It?ll look for the A record next, but until
it?s got the MX record it doesn?t know what A record to ask for.)

If there is doubt about what name server is being used you could use
tcpdump to find out.

sudo tcpdump -np -i br0 udp port 53

Replace br0 with your own network interface. You?ll need to check at
least loopback (lo) and any real network interfaces.

Dig...mx returns instantly with the correct answer too



--
?I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most
obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which
they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.?

? Leo Tolstoy


--- PyGate Linux v1.5
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On 19.11.2025 10:11 Uhr The Natural Philosopher wrote:

On 19/11/2025 07:56, Marco Moock wrote:

On 18.11.2025 15:27 Uhr The Natural Philosopher wrote:

from=<oil-monitor@heating-controller>

That is your first problem. Us a real existing address for that.

No. I wont. Because it is effectively private intra domain email.

Then make sure your postfix doesn't check that. It seems for me it does.


--
kind regards
Marco

Send spam to 1763543504muell@stinkedores.dorfdsl.de


--- PyGate Linux v1.5
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

The Natural Philosopher <tnp@invalid.invalid> writes:

So no, I don't know what it is now using as a DNS client.

Its very odd. I just did this...

# dig vps.templar.co.uk

; <<>> DiG 9.16.50-Raspbian <<>> vps.templar.co.uk
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24512
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; COOKIE: 7f7ca1b95493f5c601000000691d9a18750f0123b174788b (good)
;; QUESTION SECTION:
;vps.templar.co.uk. IN A

;; ANSWER SECTION:
vps.templar.co.uk. 3726 IN A 185.113.128.151

;; Query time: 9 msec
;; SERVER: 192.168.0.101#53(192.168.0.101)
;; WHEN: Wed Nov 19 10:21:12 GMT 2025
;; MSG SIZE rcvd: 90
...then this...
root@heating-controller:/var/ramlog# echo "This is more bollox isn't
it?" | mail -a "From: oil-monitor@heating-controller" -s "another
message" superroot@templar.co.uk
...and this...
root@heating-controller:/var/ramlog# mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
C459D1FE2E 387 Wed Nov 19 10:21:48 oil-monitor@heating-controller
(Host or domain name not found. Name service error for
name=vps.templar.co.uk type=MX: Host not found, try again)
superroot@templar.co.uk

-- 0 Kbytes in 1 Request.

Now unless dig is using some other means than postfix to look up DNS,
it looks like the problem is in postfix somehow.

Maybe, but the above doesn?t prove it; you?ve asked for an A record but
Postfix asks for an MX record, so your lookup won?t have populated the
cache (if there is one). (It?ll look for the A record next, but until
it?s got the MX record it doesn?t know what A record to ask for.)

If there is doubt about what name server is being used you could use
tcpdump to find out.

sudo tcpdump -np -i br0 udp port 53

Replace br0 with your own network interface. You?ll need to check at
least loopback (lo) and any real network interfaces.

--
https://www.greenend.org.uk/rjk/

--- PyGate Linux v1.5
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

On Wed, 19 Nov 2025 16:32:49 +0000, Mike Scott wrote:

On 19/11/2025 12:18, The Natural Philosopher wrote:

On 19/11/2025 11:13, Mike Scott wrote:

On 19/11/2025 10:33, The Natural Philosopher wrote:

# dig vps.templar.co.uk

dig -t any .......

essentially the same result, but thanksÿ anyway...

Hmm, interesting, the result depends, it seems, on the dns server:

Some DNS admins don?t like the idea of any kind of ?wildcard? or ?all information? queries: they want you to specifically ask for what you want,
no casual browsing permitted.

--- PyGate Linux v1.5
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

Marco Moock <mm@dorfdsl.de> writes:

On 19.11.2025 10:11 Uhr The Natural Philosopher wrote:

On 19/11/2025 07:56, Marco Moock wrote:

On 18.11.2025 15:27 Uhr The Natural Philosopher wrote:

from=<oil-monitor@heating-controller>

That is your first problem. Us a real existing address for that.

No. I wont. Because it is effectively private intra domain email.

Then make sure your postfix doesn't check that. It seems for me it does.

That is obviously not going to cause a temporary failure looking up the
MX for vps.templar.co.uk. Just look at the logfile fragment rather than guessing blindly. We know what the error is and it?s absolutely nothing
to do with source address validity.

--
https://www.greenend.org.uk/rjk/

--- PyGate Linux v1.5.1
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)