On Thu, 27 Aug 2020 12:44:11 -0400, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> It looks like send() itself is returning EACCES, which seems just
> weird. The send(2) man page does cite some possible causes of
> EACCES, but none of them seem relevant here.
Oh, send(2) on OpenBSD [1] says that the firewall may cause such an
error. I guess no one ever hits* this since on Linux this is "very
unlikely" to happen.
I think the problem is my cron fiddles with the vm's firewall at the
same time. I'll look into that possibility. Thanks for the hint!
* according to my web search :p
[1]: https://man.openbsd.org/send.2#EACCES
Daniel