i still have timeouts now and then according to SmarterMail logs 80085. when i check this locally on the server with nslookup it works super fast and flawless.
Also I have now used all possible known nameservers like 9.9.9.9, 8.8.8.8, 8.8.4.4, 1.1.1.1, 1.0.0.1 etc. and with all of them this error occurs.
On the server I have also uninstalled the GlassWire tool which means it can no longer have any influence. But the problem remains sporadically.
Here is an extract of a few such errors according to the log
[2023.07.26] 18:05:50.511 [A]:w3.org.uribl.swinog.ch | Time: 10001, Exception: Query 1316 => w3.org.uribl.swinog.ch IN A on 8.8.4.4:53 timed out or is a transient error.
[2023.07.26] 18:05:50.714 [A]:www.cg24.com.in.dnsbl.org | Time: 10001, Exception: Query 38995 => www.cg24.com.in.dnsbl.org IN A on 8.8.8.8:53 timed out or is a transient error.
[2023.07.26] 18:06:00.527 [A]:www.cg24.com.in.dnsbl.org | Time: 10015, Exception: Query 48107 => www.cg24.com.in.dnsbl.org IN A on 8.8.4.4:53 timed out or is a transient error.
[2023.07.26] 18:06:00.730 [A]:cg24.com.in.dnsbl.org | Time: 10015, Exception: Query 56783 => cg24.com.in.dnsbl.org IN A on 8.8.8.8:53 timed out or is a transient error.
[2023.07.26] 18:13:11.493 [TXT]:mail49.suw11.mcdlv.net | Time: 19999, Exception: Query 63461 => mail49.suw11.mcdlv.net IN TXT on 8.8.4.4:53 timed out or is a transient error.