Andrew C Aitchison wrote: > On Wed, 28 Sep 2022, Victor Sudakov via Exim-users wrote: > > > Dear Colleagues, > > > > Has anyone had problems recently sending to aspmx.l.google.com ? > > Yes. This is a known issue > https://bugs.exim.org/show_bug.cgi?id=2907 > > The bug is not actually in exim, but in Linux kernel TCP Fast Open code > shipped by at least Debian.
Thank you, Andrew! I had been unable to google up the problem for some reason. Setting `sysctl net.ipv4.tcp_fastopen=0` has helped and the mail in question has been delivered. At least this proves the real cause of the problem. I wonder what I will lose if I leave net.ipv4.tcp_fastopen=0 on the mail server (not very loaded)? -- Victor Sudakov VAS4-RIPE http://vas.tomsk.ru/ 2:5005/49@fidonet -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
