Guess I deserved the sarcasm on that one, although didn't want to create a
behemoth of an initial post.
It's not a hints db issue, I tend to purge the contents of
/var/spool/exim4/db/ each time I run a test to ensure there's nothing being
cached. The debug below shows that EXIM is getting the 3 hosts returned
from "queryprogram", and appears to successfully resolve the higher
priority outlook.com MX's but it almost seems that the HOST_NOT_FOUND on
the third invalid domain results in the whole delivery being aborted. I
don't have control of the recipient domain here, the use of an invalid MX
with a really low priority is apparently recommended by Outlook.com to
validate domain ownership (no idea what's wrong with the TXT record
approach tbh).
calling special_xheader_pane router
special_xheader_pane router called for test.user@???: domain =
eurocross.nl
requires uid=114 gid=120 current_directory=/
direct command:
argv[0] = '/usr/bin/pane_lookup.pl'
argv[1] = '$domain'
direct command after expansion:
argv[0] = /usr/bin/pane_lookup.pl
argv[1] = eurocross.nl
command wrote: ACCEPT HOSTS=astrumalliance-com.mail.protection.outlook.com:
eurocross-nl.mail.protection.outlook.com:
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid
set transport remote_smtp_special_pane
finding IP address for astrumalliance-com.mail.protection.outlook.com
doing DNS lookup
astrumalliance-com.mail.protection.outlook.com in "*"? yes (matched "*")
DNS lookup of astrumalliance-com.mail.protection.outlook.com (AAAA) gave
NO_DATA
returning DNS_NODATA
DNS: no SOA record found for neg-TTL
writing neg-cache entry for
astrumalliance-com.mail.protection.outlook.com-AAAA-4900041, ttl -1
DNS lookup of astrumalliance-com.mail.protection.outlook.com (A) succeeded
fully qualified name = astrumalliance-com.mail.protection.outlook.com
astrumalliance-com.mail.protection.outlook.com 104.47.6.36 mx=-1 sort=-293
astrumalliance-com.mail.protection.outlook.com 104.47.5.36 mx=-1 sort=-60
finding IP address for eurocross-nl.mail.protection.outlook.com
doing DNS lookup
eurocross-nl.mail.protection.outlook.com in "*"? yes (matched "*")
DNS lookup of eurocross-nl.mail.protection.outlook.com (AAAA) gave NO_DATA
returning DNS_NODATA
DNS: no SOA record found for neg-TTL
writing neg-cache entry for
eurocross-nl.mail.protection.outlook.com-AAAA-4900041, ttl -1
DNS lookup of eurocross-nl.mail.protection.outlook.com (A) succeeded
fully qualified name = eurocross-nl.mail.protection.outlook.com
eurocross-nl.mail.protection.outlook.com 104.47.6.36 mx=-1 sort=-454
eurocross-nl.mail.protection.outlook.com 104.47.4.36 mx=-1 sort=-83
finding IP address for f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid
doing DNS lookup
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid in "*"? yes (matched "*")
DNS lookup of f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid (AAAA) gave
HOST_NOT_FOUND
returning DNS_NOMATCH
faking res_search(AAAA) response length as 65535
writing neg-cache entry for
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid-AAAA-4900041, ttl 10800
DNS lookup of f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid (A/AAAA)
requested AD, but got AA
DNS lookup of f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid (A) gave
HOST_NOT_FOUND
returning DNS_NOMATCH
faking res_search(A) response length as 65535
writing neg-cache entry for
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid-A-4900041, ttl 10800
DNS lookup of f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid (A/AAAA)
requested AD, but got AA
DNS lookup failed: trying getipnodebyname
gethostbyname2(af=inet6) returned 1 (HOST_NOT_FOUND)
gethostbyname2(af=inet) returned 1 (HOST_NOT_FOUND)
no IP address found for host
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid
LOG: host_lookup_failed MAIN
no IP address found for host
f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid
special_xheader_pane router: defer for test.user@???
message: lookup of host
"f3f99c48-a706-4deb-9c63-5fa9e6153130.msv1.invalid" failed in
special_xheader_pane router
added retry item for R:test.user@???: errno=-32 more_errno=0
flags=0
On Wed, Feb 24, 2021 at 12:21 PM Jeremy Harris via Exim-users <
exim-users@???> wrote:
> On 23/02/2021 15:34, Adam Low via Exim-users wrote:
> > However it seems that EXIM is ignoring the ordering of these hosts and
> its
> > unclear how it is selecting them from the list.
>
> This is why the debug facilities exist.
>
> One possibility is that the first host listed is recorded in
> your hints database as being non-responding.
> --
> Cheers,
> Jeremy
>
> --
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>